ELECTRONIC MUSIC & HOME RECORDING

ROBERT MOOG INTERVIEW THE ULTIMATE KEYBOARD

The Prophet-10 is the most complete keyboard instrument available today. The Prophet is a true polyphonic programmable synthesizer with 10 complete voices and 2 manuals. Each 5 voice keyboard has its own programmer allowing two completely different sounds to be played simultaneously. All ten voices can also be played from one keyboard program. Each voice has 2 voltage controlled oscillators, a mixer, a four pole low pass filter, two ADSR envelope generators, a final VCA and independent modula­ tion capabilities. The Prophet- 10’s total capabilities are too The Prophet-10 has an optional polyphonic numerous to mention here, but some of the sequencer that can be installed when the Prophet features include: is ordered, or at a later date in the field. It fits * Assignable voice modes (normal, single, completely within the main unit and operates on double, alternate) the lower manual. Various features of the * Stereo and mono balanced and unbalanced sequencer are: outputs * Simplicity; just play normally & record ex­ * Pitch bend and modulation wheels actly what you play. * Polyphonic modulation section * 2500 note capability, and 6 memory banks. * Voice defeat system * Built-in micro-cassette deck for both se­ * Two assignable & programmable control quence and program storage. voltage pedals which can act on each man­ * Extensive editing & overdubbing facilities. ual independently * Exact timing can be programmed, and an * Three-band programmable equalization external clock can be used. * Program increment footswitch * Ability to change programs automatically in * Programmable volume control and a master the sequence. volume control * Transpose facilities for instant pitch * Octave transposition switches changes. * Upper & lower manual balance control * A-440 reference tone The Prophet-10 comes complete with a high quality flight case, two voltage pedals and two foot- switches. It’s now available; see your local dealer. Play the Prophet-10 today —It’s your ULTIMATE KEYBOARD. For more information write to: SEQUENTIAL CIRCUITS, INC. 3051 North First Street Dept. K San Jose, California 95134 STAFF CONTENTS X

PUBLISHER ISSN: 0163-4534 John S. Simonton, Jr.

EDITOR Craig Anderton Volume 7, Number 4 JANUARY/FEBRUARY, 1982 MANAGING EDITOR Linda Kay Brumfield FEATURES ART DIRECTOR/ PRODUCTION MGR. Cynthia Rueb Chip Power By: Jack Orman...... 8 Technical Illustrator Caroline Wood Robert Moog Interview By: Jay Lee ...... 10 CIRCULATION Ramona French Peggy Walker Simple Square Wave Shaper By: Bobby Beausoleil ...... 24 BOOKEEPING Cathi Diehl Tape Timer Ruler Cut-outs By: Craig Anderton ...... 34 PRINT PRODUCTION Kay Schwartz SEMCO Color Press COLUMNS

POLYPHONY (ISSN 0163-4534) is published Practical Circuitry: VCA's Made Simple bimonthly at 1020 W. Wilshire Blvd., By: Tom Henry ...... 16 Oklahoma City, OK 73116, by Polyphony Publishing Co. Entire contents copyright (c) 1982 by Polyphony Publishing Co. All Re-View rights reserved. No portion of this By: Robert Carlberg...... 21 publication may be reproduced in any manner without written permission from the publisher. Second Class postage is Details: Gozinda & Gozouta Revisited paid at Oklahoma City, OK 73125. By: Dennis Bohn ...... 22 ADVERTISING rate card and deadline schedule is available upon request. On Location: 1981 computer Music conference Contact Linda Brumfield at (405) By: Don wilson...... 14 842-5480. DEALERS & DISTRIBUTORS bulk prices are available upon request. Contact Linda REVIEWS Brumfield at (405) 842-5480. SUBSCRIPTION rates: American 1 year 12.00 Casiotone Model 202 review 2 years! 22.00 Foreign 1 year 14.00 By: Mark Styles ...... 28 years 26.00 We now accept MasterCharge and Visa Product Review: Korg Trident payment for subscriptions, back issues, and PolyMart items. Foreign payments By: Bill Rhodes ...... 30 must be by charge card, money order, or certified check in US funds drawn on a US bank. HELPFUL HINTS BACK ISSUES are available at $2.50 each ppd. Send SASE and request our 'Back Issue List' for a complete index of issues and their features, or see the Cable Test Fixture back issue ad in this issue. By: David Fuglewicz ...... 15 CHANGE OF ADDRESS notifications must include your former address and zip Repair Tip code, and any numbers from the mailing By Richard Sloan ...... 15 label, as well as your new address. When you move, be sure to notify your post office that you DO want second Promotional Tip class and controlled circulation By: "Buffalo" Bob Brittain ...... 31 ublications forwarded. This will save Post or returned issues. Polyphony is not responsible for replacement of lost or returned issues when we have not been REGULARS supplied_ with change of address information.

TO POSTMASTER, send address changes to: Editors Note ...... 4 Letters ...... 6 POLYPHONY Current Events ...... 20 PO Box 20305 Oklahoma City, OK 73156 Equipment Exchange Classified ...... 33 Ph. (405) 842-5480 Advertiser Index ...... 27

V J V POUPHONU January/February 1982 3 you are legally (and I feel morally) obligated to1 (EDITORSdeclare your income--- as well as collect sales taxes for the state. However, there are a number of books out on how to run a small business that should be of great help. Who knows? Your casual sideline could eventually turn into a steady job. • When you have money, put it back into the Recession? What recession? hands of other musicians. I recently needed to have If you just got laid off your job yesterday, some work done on my car. Two mechanics were recom­ then that might not seem funny at all. But hear me mended to me, with equal skills and equipment. How­ out - the subject of this month's "Editor's Note" is ever, one managed a band and the other one did how you can make the most out of bad economic times, not...guess who got my business! And while you're because there are always ways to turn obstacles into at it, guess which one had a mixer that needing opportunities. fixing and was willing to pay me to look at it? The conventional wisdom says that during times • Support musical events and endeavors run by of economic hardship, the entertainment industry not musicians. If at all possible, why not make a only survives, but in some cases even prospers. The promise to yourself to buy at least one independent­ reasoning is that people need escape more than ever ly marketed record a month? The "Big 3" record during hard times, and since they aren't going to be companies may be crying the blues, but feisty little packing their bags for a European vacation, they'll musician supported labels are doing better than end up going to the movies or buying a record in­ ever...do what you can to help them along. You'll stead. In fact, at a NAMM show two years I asked a improve the lot of your fellow musicians and get number of companies if they feared the recession turned on to some great new sounds in the process. which, at least to me, seemed to be fast approaching If there's a club in your area that is switch­ • (and which since then has come upon us in full ing over to a policy of presenting live music, force); the answer was almost universally "no", patronize the place; the next act they hire might be whereupon the company representative would say some­ your band. thing about entertainment prospering during reces­ sionary times. The important point about all this is that But, conventional wisdom doesn't seem to be musicians live in a bit of a closed environment. quite as accurate as it once was, and considering For example, the guy who tests effects for the XYZ how many music companies have hit the skids recent­ Effects Company takes his paycheck and buys a re­ ly, I don't think that we can take anything for cord...the artist who made the record takes the granted any more. If we are to maintain our musical royalties and spends them on an XYZ Flanger. An standard of living, we can't just assume that be­ astute Polyphony reader who's a friend of the mu­ cause entertainment did all right in the past, then sician offers to add the "XYZ Flanger Echo Mod" in it will do all right in the future: we're going to an issue of Polyphony for a nominal fee; the reader have to make a concentrated effort to keep finan­ takes the money and goes to a local club to catch cially afloat. Here are some ideas on how to cope the band; the band members get paid, and one of with a recession and still maintain your musical them, after hearing about a guy who modifies XYZ jollies.• Flangers, gives our astute Polyphony reader another modification job; the reader then adds some more • Do-It-Yourself. Anything you can do your­ mods, writes it up for Polyphony, takes the money we self is going to save you money and increase your pay him and buys some more records and parts, and so knowledge. Can't afford a spiffy new echo unit? on...you get the idea. Don't worry about it. Pick up a used tape recorder I guess it comes down to the old saying that we at a garage sale, spend a couple of bucks on some had better hang together, or surely we'll all hang new heads, and you'll have a fine echo unit for a individually. There are ways to beat the "system" - fraction of the cost of commercial equivalents. But all we have to do is stick together and support each you say you don't know how to add heads? Then get a other. Hopefully the world won't fall apart around Poly Paks assortment of 5 heads for $1 and experi­ us; but if it does, at least we'll go out playing ment! Remember, you're dealing with a clunker tape our axes and humming a tune. recorder and it's doubtful that you'll make things worse. In fact, you might learn a whole lot in the process. • Make your subscription to Polyphony work for you. Every issue has at least one modification or construction ar t ic 1 e... why not re-wire a friend's guitar, for example, and make a few bucks off of that endeavor? When times are bad musicians may not have the bucks to buy a new guitar, so they'd rather do what they can to improve the one they've got. You can be a part of those plans, and reap the rewards. You only have to do one or two modifica­ tions to make your subscription to Polyphony pay for

4 POUPHOM January/February 1982 FOR PROFESSIONAL USEONIY. THE 1ASCAM122 STUDIO CASSETTE RECORDER.

Tascam. Now we’ve designed Performance plus a combi­ Dolby Headroom Extension. a cassette recorder for the nation of features makes the Gives you up to lOdB more studio. One that has every­ 122 a tool of the trade, not a headroom over 10 kHz. Cassette thing you need to reproduce plaything. dubs end up hotter, fuller, cleaner your studio sound faithfully. . when played back on any stan­ dard Dolby * B deck.

Three-head System. Front Panel Trimmers. Two-speed Transport. Separate record and repro­ The kind of fine-tuning you’re You get 1V8 ips plus 3 3/ 4 ips, duce heads are mounted in used to having on studio a two-position pinch roller a single housing, eliminating machines. Notice the parallel for cueing in the pause mode azimuth error. line inputs in place of hi fi and a capstan motor that microphone inputs. doesn’t idle needlessly in the stop mode, for long-term Plus Options. Like full reliability, transport remote control and dbx.* Check out the 122’s qualifications at your Tascam dealer. When you want the best you can get, it pays to use a professional.

©1981 TEAC Corporation of America, 7733 Telegraph Road, Montebello, CA 90640 * Dolby and dbx are registered trademarks. POUPHONy January/February 1982 5 CORRECTIONS AND ADDITIONS MORE CHANGES HELP!

I noted some errors and would There are a couple of errors I have an encoded PAIA key­ like to make some additional com­ in my article, "Psycho-Acoustic board (with D/A and Quash), and a ments about the SuperController Experiments", which should be TRS-80 I'd like to interface with article, so here goes: mentioned. my synthesizer. However, I lack • S2 should not have a posi­ Fig. 2a should show a enough knowledge to devise my own tion going to ground; remove the connection between the 4730-2 machine language program to inter­ line to ground right above C5. output to VCA-2 input. Also, the face the two. Can any reader help • There is no C4, so if empty box between the VCAs and the me in obtaining an interfacing you've been looking for it, stop! -3L should be labelled "REVERB". schematic and an interrupt routine • By wiring the footswitch Fig. 2b: The 4730 output to refresh the Quash for a TRS-80 jack as shown below, you can elim­ going to the carrier input of the Level II microcomputer? inate the "on" position of S4. modulator should be labelled as LP (although BP also gives some nice Michael D. Buck l_£? foot posi­ effects). 4159 Commonwealth tion of S4 Fig. 3 should show a 5V bias Toledo, OH 43612 voltage into the CV input of the (419) 478-4088 • The gate jack should be 4730. wired as shown below: Fig. 4: The last line of the -- R21 isntructions should say: "Choose POT VALUES slowest rate of Sweep, minimum +5V resonance/feedback and widest In the July/August issue, possible sweep". there's the schematic for an Ana­ Fig. 6: The inverter is log Programmer. My question is, • The resistor off of pins 5 controlled by the VARIABLE output what size pots does one use? I'm and 6 of the 4001 should be R22, of the ADSR-1. This was not new to all this and found no re­ 100k. labelled. ference to their values; can you • The 4001 should be label­ That's it for now. help me out? led "each gate = 1/4 4001". • C12 should be .01 uF, not Charles Lauria Joel Graham • Figure 3 should have the Towaco, NJ 07082 mode switch in the DELAY position. Joel - Sure. You can use Sorry for all these errors, I anything from 50k to 500k linear had so many revised schematics taper pots, with 100k linear being around that I didn't know if I was MORE COMPUTERS! the preferred value. coming or going. Also, here's a tip for the Re Polyphony: I would like AMS-100 fans out there. When I to suggest that you try to broaden DATA BOOKS NOT EXTINCT first tried out the VCA/VCD module its base, away from (without ne­ (DEVICE 1:8:79), there was an glecting) the experimenter, to I'm writing in regards to annoying buzz at all volume other aspects. My own interest in Marc Briand's letter (July/August levels; it seemed to be due to the electronics is strictly prag­ issue), where he asked about ob­ leakage from the overdrive stage matic: I'd rather make music than taining data books. In my most (IC2). So, I hooked up a DPDT fiddle with a breadboard. recent issue of Electronic Design, switch with one pole wired as Incidentally, I'd like to see National advertises the Linear specified in the article. I then some stuff on music applications Data Book as being available for broke the connection between pin 6 for computers, if you can round $9.00 from National Semiconductor, of IC1 and C2, and installed the something up. Also, something on PO Box 70818, Sunnyvale, CA other half of the switch to these a double keyboard polyphonic syn­ 94086. Delivery takes 4-6 weeks, connections. Thus, in the VCA thesizer, with individually tuna­ and Californians need to include mode, IC2 and its associated cir­ ble keys (commercial gear with appropriate sales taxes. Write cuitry is completely removed from those capabilities cost many kilo- them for information on what other the circuit. That simple change bucks) . books are available. made my VCA/VCD work like a charm. Rev. Jones Greg Vizzi Thomas Henry Groton, CT Belle Vernon, PA 15012 Iowa City, IA

6 POUPHONy- Jin man / Febn mr i • l 982 IS NEW ALWAYS BETTER?

I'd like to mention a few great deal of technical resources something that everyone must con­ things I've often considered when are using them to compensate for sider carefully on an individual reading your magazine, and which their own inadequacies; but it is basis. might interest your readers. One true that in many cases these I think that about takes care thing that is plain for all to see resources are grossly underused. of that, except that I have also about electronic music is that it The tremendous capability of elec­ enclosed money for the renewal of is tremendously expanding. This tronic instruments for musical my subscription to Polyphony, and is brought about by its intimate subtlety is too often abandoned in that I am grateful for its exis­ relationship with technology. In favor of the more dramatic novelty tence. fact, for people like myself elec­ of "the sound that no one has tronic music is attractive for heard before". This is of course David Dana both its musical and scientific more evident in popular music, but Horseheads, NY aspects. But one thing that is I think we've all fallen into the disturbing is the intoxicating trap at one time or another. We novelty of the new instruments should always think twice, if not PA INFORMATION which are constantly making their thrice, when we find ourselves predecessors "obsolete". The thinking "if only I had that piece Jim Falwero's letter in the natural tendency for all of us is of equipment". One must always Sept/Oct issue expressed his grief to forget that synthesizers, like decide whether the cycle isn't on his P.A. problems. I wish to most other instruments, have a simply going to go on indefinite­ recommend The P.A. Bible from potential that is primarily ly . Electro-Voice, and a series of limited by the performer's creati­ This cycle is not only a bad supplements to the main pamphlet. vity. Often I have been dissatis­ excuse for one's limitations, but This covers everything he needs to fied with my own creative abili­ an instrument that is constantly know to have a basic working know­ ties, but blamed it on the limita­ changing (even if it is expanding) ledge of P.A. use. Write Electro- tions of my electronic equipment. can be a serious detriment to the Voice for more info at 660 Cecil It takes listening to the music of expression of one's creativity. Street, Buchanan, MI 49107. Al­ a real master to make me realize In short, I think we could all so, Recording Engineer/Producer where the fault lies. Now of benefit from firm restraint and has regular articles on concert course this is a difficult idea to self-evaluation when dealing with sound reinforcement. reckon with; what are all the any form of self-expression, and factors involved? It is certainly especially from an awareness of Rich Moroni not true that all those who use a our own limitations. This is Chicago, IL

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PQUPHONU January/February 1982 7 While I was impressed with the 25 Watt Sanyo amp circuit in DEVICE 1:10, for PA I needed more this point with a single—wire power. This article describes a ground. The one exception to this higher power amp built around is the speaker ground, which either the Sanyo STK-050 (50 should be isolated from the cir­ Watts) or STK-070 (70 Watts). cuit ground and connected directly How it works. Figure 1 is an to the power supply ground. When amp circuit that can use either Fig.1 I first built this circuit, I had the STK-050 or -070 (the only dif­ the speaker ground tied to the ference is supply voltage). The and 3 show power supply designs circuit ground. The resulting signal AC couples through Cl to for the chips. For the j^35V sup­ high frequency oscillation caused pin 1, the non-inverting input. ply, make up a 50V center-tapped the chip to overheat, and while An internal resistor from this pin transformer from two commonly the internal protection circuitry to ground sets the input impedance available 25V models (Radio Shack prevented any damage, the clipping at about 30k Ohms. Pin 5 is the #273-1512 or equivalent). The distortion was severe. Once the inverting input; RI and Cl connect secondaries must be properly speaker ground was returned dir­ from this pin to ground to form phased to generate the correct ectly to the power supply, the part of a feedback loop which sets output voltage; if the output oscillations ceased, the chip the amount of gain. An internal voltage of the supply is much cooled down, and the distortion 29k resistor (Rf) is available at lower than expected, reverse the stopped. pin 4 to complete the loop, or it 3.5 A can be left unconnected and an external resistor used in conjunc­ 0 + 42V tion with pin 5. Using the formu­ la for the gain of a non-inverting

amp, Av - 1 + (Rf/Rl), for RI = lk 117 VAC O and the internal resistor = 29k the gain is 30 (this allows a signal of about IV rms to drive 4T « the amp to full power). Pins 10 and 13 are connected to the chip's on - off Fig. 3 power transistors and should be connections of one of the trans­ tied to the output through 0.22 Heat sinking. Make sure that former's secondary wiring. Either Ohm, 2 Watt resistors. you coat the metal back of the

Power supplies. Pin numbers of the power supplies should be power amp chip with heat sink for both chips are the same and fused with a 3.5A, fast-blo fuse. grease and mount it in firm con­ Grounding. Pin 3 is the only the power supply voltage tact with the metal chassis or differs. The STK-050 needs +35V circuit ground, and all of the other appropriate heat sink. and the STK-070, +42V. Figures 2 grounded components should tie tc These chips, because of the extra power generated, run slightly hot­ ter than the STK-054 or -56 but nevertheless you should be able to hold your hand on the case while the amp is in operation without discomfort. I found these amps to be clean sounding and every bit as powerful as rated. At present I am using the 70 Watt chip to drive part of my PA system, with excel­ lent results. January/February 1982 SOUND DELIGHTS / ------PHASEFILTER™ "'TIME MACHINE “ 1 PARTS LIST o o o o Power Amp (Fig. 1) O O 3 "* o O A CL p " | | - y j | RI lk, 1/2 W, 10% ; jj O O O R2, R3 0.22 Ohm, 2W a t 3»cii 9 3 3 p O O 3 p 5 © © © R4 4.7 Ohm, 1/4W Cl 1 uF, 6V min TIME MACHINE $298 PHASEFILTER $129 C2 22 uF, 16V min C3, C4 10 uF, 50V min C5, C6 0.01 ceramic disc C7 0.047 ceramic disc

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r M astefCard V J 91 ELM STREET PHOENIX SYSTEMS MANCHESTER CONNECTICUT 06040 203-643 -4484 PQUPHONy January/February 1982 9 11 What more can be said about Bob Moog that hasn't been said already? The inventor of it all, the man who started the revolution, etc. But what can be said for the man is his incredible humility, and his almost puzzling lack of understanding of what he has contributed to the electronic musical scene. I've known Bob for eight years now, and without question he is the most mystical man I've ever come across - and yet at the same time, the most straightforward. The first time I met him he walked into my apartment with his wife Shirley, sat down and listened to some music, ate some quiche, listened to some tapes and said "Gee, that sounds like good s— t". Then he looked over my E-mu system and said "My God, all those attenuators. My, how times have changed". That was about it. Bob is truly a remarkable human being, as well as a remarkable engineer. Whether or not he was the first to come up with the synthesizer concept or not is totally irrelevant - Bob Moog stands alone. He is a man to be admired, and I hope this interview portrays that. | By: JAY LEE INTERVIEW: ROBERT MOOG

Jay Lee: What was your first electronic music pro­ center resorted to making their own consoles, micro­ ject, and did it, work? phone preamplifiers, frequency shifters, ring modu­ lators, and so on in the 50s, I went to work making Robert Moog: Well, I haven't thought about that one tape recorders as well as oscillators in the late for a long time...I really can't remember what the 60s. Up until about 1968, our clients were the first project was, I was just too young. My father, electronic music studios and universities. Most of in his early days, was one of the first radio ama­ them couldn't afford to buy an Ampex 8 track re­ teurs. Even when I was a kid, he was experimenting corder, and there was no such thing as a 4 track with very simple electronics. He used to like to recorder on quarter-inch tape that you could just fix radios and build this and build that. I can buy at your local hi-fi store. At that time, a four remember building a one tube, battery-operated radio channel tape recorder head was something very spe­ - just a detector and amp circuit - and building a cial; you had to special order it, and a reasonably two tube radio that actually developed enough volume priced deck with solenoid controls was also some­ to drive a loudspeaker. I guess I was about eight thing special. Putting that kind of capability or nine years old at the time when I did those along with sel-sync was unique at that time. In the projects with my father. late 60s, someone who wanted to set up a small By the time I was a teenager, I had eased into studio with a 4 channel tape recorder could not do working by myself and could open up Radio News or it at the price we were charging - around $1500 - Popular Electronics to build something out of there with anybody's equipment but ours. That's why we for myself. Just about everything I built worked designed a multi-track tape recorder. Nobody else sooner or later, but I can't remember anything I was building an affordable tape recorder that was ever built that worked right off. suitable for multi-track tape work. It's hard to imagine all that now considering that Teac's been JL: When you first were getting started, you de­ selling 4 tracks for 10 years. Now you can get 8 signed and marketed everything from tape recorders tracks on quarter inch and Portastudios with 4 to oscillators. What was your philosophy behind tracks on a cassette, and everybody around the world this? is into putting together music on tape. This was not the case from 1965 to 1970. RM: Our philosophy was that we saw ourselves as suppliers to electronic music studios. For the same JL: What about mixing consoles? reasons that the Columbia-Princeton electronic music

10 POUPHOM January/February 1982 I RM: When it came to mixers, you couldn't get a JL: Who purchased the first Moog, and what's the simple mixing console, suitable for electronic music story behind it? composition, where you could mix down into four output channels and continuously control the amount RM: The person who purchased the first Moog is of a given input in any of the four channels. different form the person who has the first Moog. Columbia-Princeton had mixers like this, but they The first Moog synthesizer was all the prototypes made them themselves. The mixers we made had a that I built before we offered the equipment commer­ matrix of attenuators, where the inputs were columns cially, and that prototype system is owned by Herb of the matrix and the outputs were the rows, and you Deutsch, who is now the marketing and sales manager could mix any amount of input into any of the four of Moog Music. The first paying customer was Alwin outputs. Nikolais, who is a choreographer in New York City. So that's why we made tape recorders, mixers, His dance troupe is well known. In addition to and things like power oscillators to change tape choreography, he has always designed his own light­ speed. You couldn't buy anything like that for less ing, produced his own music, and designed his own than twice or three times what we were charging. As costumes. He does the whole schtick. Before he met a result, we designed and installed a great many me he was making music with tape recorders and packages - what are today called "turnkey" systems. microphones and not much else. It was very good The first one was delivered to the University of music, very suitable for dance. He's just one of Buffalo. For $25,000 we equipped the whole studio, these guys with incredible talent and taste. starting with the bare room. We eventually acquired Anyway, I was exhibiting at the October 1964 a Scully dealership and then equipped a dozen, maybe AES show in New York City. I had four hand-made two dozen, university studios from the ground up. modules in a hand-made wooden case on a card table About the only thing we didn't supply was the furni­ with a tablecloth, and was surrounded by all these ture . big tape recorder and mixing console manufacturers. I felt just like a eunuch in a harem. But then JL: What do you consider to be your most important Jimmy Seawright, who was a technician with the breakthrough in synthesizer design? Columbia-Princeton electronic music center, saw what RM: (Long pause) You know, there was no "break­ I had and said he knew of someone who would be through". I guess technically the most notable interested. He disappeared, and three hours later thing I did was the voltage controlled filter. But showed up with Alwin Nikolais. He saw what it was, I think that the most important thing I did in the lit up, placed an order, and a couple of months late 60s was put all the elements of a system to­ later we delivered our first synthesizer system for money. gether. The ideas of control voltage, of an expon­ ential relationship between the control voltage and frequency, of keyboard control, of a ribbon control­ JL: Who were some of the people who played a role ler, of modular organization with compatible signal in helping you develop the modular Moog? What were levels, the idea of putting it all in a box with a their contributions or input? handle so that you could carry it around, were all new. I spent endless months and years talking to RM: (With emphasis) Every customer we had in the musicians, giving little lectures, showing musicians first 2 or 3 years contributed something. It's hard how to use this stuff, removing all the obstacles to think of anyone who didn't have some idea. With that musicians had to applying electronics to compo­ Herb Deutsch, in early 1964, we evolved the concept sition. Sometimes a person's contribution is not a of the VCA and VCO. We also came up with a keyboard single, striking invention, sometimes it's just with very simple envelope generators, but there was putting it all neatly in a box. I think that was my no sample and hold (no memory in the keyboard) so contribution at the time. the envelope generators didn't have any release

Sometimes a person’s contribution is not a single striking invention, sometimes it’s just putting it all neatly in a box.”

JL: How did the modular concept evolve? time. When you let go of the key, the note stopped. Anyhow, by the time Herb and I finished our work at RM: It always seemed natural to me. I began in the end of the summer of 1964, we had the basic idea 1964 with this modular business, but years before of a modular system, the basic idea of voltage that, in 1961, Harald Bode published an article in control, the basic idea of a keyboard that produced Electronics magazine on a modular system he had control voltages, and simple envelopes. From designed. It was not a complete modular system, but Nikolais...let me think...we might have gotten the he had the forerunner of a voltage controlled ampli­ idea of a ribbon controller. From Eric Siday we got fier, reverb unit...well, I don't know what all the idea of a bank of oscillators controlled by a else, but it was definitely a modular system that single control voltage. His first system had some­ sat in a rack and was patched together with phone thing like six or eight oscillators controlled by a plug patch cords, the same way as our stuff. single controller. From Vladimir Ussachevsky we got So, the very first thing I built was a bread­ the idea of four part envelope generators. What board with a voltage controlled oscillator, another everybody calls "ADSR" today, like it was engraved breadboard with another VCO, and a third breadboard in stone, came right out of Ussachevsky's require­ with a VCA. All the inputs and outputs used jacks, ments and specifications. Also the envelope fol­ and that's how the modular synthesizer evolved. lower, and the idea that a VCA should be either

POUPHONy January/February 1^82 11 exponential or linear with well-defined control didn't we come out to the AES show in Los Angeles to characteristics came from Ussachevsky. Gustav Cia- show our stuff, and maybe he could be our represen­ maga of the University of Toronto electronic music tative. That was the beginning of an incredibly studio specified the first VCF. I designed it, but successful collaboration. Paul was our West coast he specified how it should work. Carlos had quite a rep and did very well. He sold hundreds of thou­ bit to do with the filters, and also improving the sands of dollars worth of modular systems to West keyboard. That was at the beginning. A great deal coast musicians from 1967 to 1971 or so. At the end of what we did together became standard. Keyboard of 1970, there was a recession, the market was with memory was one thing we worked on together, temporarily saturated with modular system, and we certainly the fixed filter bank was another. I were stuck with an inventory that was much bigger guess by the time 1967 ended, we more or less had than our ability to pay for it. We had no customers all of the basic ideas in place, and then we began to sustain cash flow so we had to sell out. It was cranking the stuff out because the demand began to very tempting then to pack it all up, in fact not accelerate. only pack it all up but throw it in the garbage and declare bankruptcy - but we didn't. Then from 1971 JL: There has long been the question of who was to 1977 I was working for somebody else, which was first, you or Don Buchla, in the design of the by and large a difficult, gripey experience for me modular voltage controlled synthesizer. Could you because there was a lot of politics and there was a shed some light on this? corporation at the top that didn't understand the market, my capabilities, or the customers. RM: I don't know who was first. I do know when we These were the main frustrations that occurred started working on modular synthesizers. I can tell during the last 14 years or so. There haven't been you that we knew nothing of Buchla, and I have to any frustrations like that recently, because I am my think that he knew nothing, or very little, about own boss again and I haven't gotten into something us. I began working myself in the spring of 1964, deeper than I can control. and had actually shown stuff in public during Octo­ ber of 1964 after showing it at the University of JL: What are you working on these days? Any new Toronto in the summer of 1964. My understanding was projects? that Buchla was working at the same time. I would say that we took parallel paths, because the techno­ RM: I' m just finishing building a house that I've logy and requirements of the musical world were such been working on for three years. It's in the woods. that the modular approach just made sense at that It's a fairly big house...I've done all the time. electrical work, plumbing, and heating. My wife and I put down all the floors, and now we're just about done. I'm setting up a shop to build custom and JL: What do you think of the modular approach now? limited production of electronic music instruments that stress well-designed, smooth-acting, easily RM: It has to be the most versatile way of getting controllable control devices - control surfaces. fairly rapid access to shaping sound. I still think I'm building a performance synthesizer right now it's musically useful. On and off, there have been that's polyphonic, microtonal, computer controlled, competitors - particularly in the late 60s - who and touch sensitive in several ways. There are took pot shots at patch cords. Primary among them three keyboards. Each key on each keyboard is touch was ARP, who made a lot of noise about how much sensitive in four different ways: back and forth on better matrix switches were. EMS in London made the key, side to side on the key, up and down, and noises about how pin matrixes were better, but the the fourth way is that once the key is down, fact is that nearly all successful modular synthesi- pressing harder gives a higher output. All of this

zers have used patch cords. Serge is modular, is controlled by computer. The capabilities are, at Roland has a modular system, PAIA has a modular this point, limited by people's ability to play it. system, E-mu, Polyfusion, and Synton - they're all It's also limited by the fact that we haven't devel­ modular. It just makes sense, because it's so damn oped that much software for it. That's what we're basic and there's no limitation on the quality. And working on now. It should be done shortly, I hope you don't spend a huge amount of money on something by the time this interview appears. After that, I that 50-cent patch cords can do perfectly well. don't know - perhaps other people will want similar instruments. JL: Was there ever a time in your career when you wanted to pack it all in and do something else? JL: How does the business of electronic music in­ fluence you now, and how has it influenced you in RM: Oh, there have been many times like that! My the past? gosh...around the spring of 1967 we were having a hard time making ends meet. There weren't that many RM: (Pause) I don't really know how to answer that customers, and we weren't making any money. Then question. How about if I said that you learn very this guy on the West Coast named Paul Beaver - who fast from your customers. I began in this business we didn't know from a hole in the ground - asked why as an engineer with no business sense and only the

12 POUPHONU January/February 1982 vaguest feeling for what it's like to be a profes­ sional performer, a creative person. Syre, I had piano lessons and I could read music, but that didn't mean that I experienced things the way a professional musician does. You very quickly learn that sound quality is extremely important, that the feel of an instrument is extremely important, that just because something is technically elegant and pleases you as a technician doesn't mean that mu­ sicians will get anything out of it. I guess last, but certainly not least, you begin to realize how important it is to make some­ thing that WORKS. When you plug an instrument in tomorrow, it has to work the same way as when you plug it in today, because what you make is something that becomes part of a musician as much as his fingers and his feet. The instrument just becomes an extension of himself, and it rips a musician up to have something that he relies on so much for his creative work crapping out on him. So you learn that these simple things - good feel, good sound, reliability, and to a lesser extent, lots of func­ tions and versatility - these are more important than you would guess just sitting at a desk pushing a pencil or looking at a meter. JL: What do you think the future holds for elec­ tronic music in general? RM: I think the electronic music medium has the potential for being more fun to a wider variety of people than any other technical/musical medium. A lot of people have learned piano, but it takes a lot of work to learn piano. Same thing with violin, JL: What's it like being a household word? drums, guitar - you have to practice them, and then you do what you can do on them. Not everybody can RM: Well...it's sometimes convenient. You come play a guitar, or piano, or sing for that matter. back from a trip abroad with a suitcase full of this When you look at something like Casio's VL-1, or all and that, and the customs official looks at your these new keyboard instruments that range from the card and says, "Moog...oh yeah, you have anything to size of a phone book to a full grown combo organ, do with synthesizers?" And I say, yes, that's me. they're just a lot of fun. It's not the sort of fun Next he says "No kidding, I play such and such in a an electronic organ of the 60s and 70s was, with all rock group" and then he gets to talking to me about those automatic gadgets - you know, you push one key his rock group, and how he likes Moog synthesizers, and it plays all the rhythm, and bass line, and and he forgets to look in the suitcase...that sort arpeggios, and with the other finger you play a of thing goes on all the time, although not all the melody. To me, that doesn't have the potential for times you'd want it to go on! (Laughs) So it's being fun. It's a very quick dead end, because the convenient in that respect. Another thing is you instrument is really nothing more than a recorder of get a lot of - "respect" is not the word - you know, people are sort of dazzled by actually coming into contact with someone who is famous with a capital "F". All that means is that the media did a job on us in the late 60s. But generally, if a person recognized the name at all, he or she doesn't know exactly what it is I did or didn't do, exactly why some very simple stuff, and all you do is turn the it is I'm famous. Most people think I have THE recorder on and off. With electronic music, it's patent for THE synthesizer, and they don't see my open-ended. You can explore as much as you want or part in the industry anywhere near like I do. I try as little as you want. You can make Polish polkas to discount that, because it's a pain in the ass. or something far out, or anywhere in between. I If you start explaining it, nobody wants to know. think that as time goes on, electronic instruments All they want to do is the celebrity trip, with the are going to become more suited for use as musical autographs and all that. Aside from those things, I tools, cheaper, and more reliable. Look how fast don't think it affects my daily life at all. it's going. Ten years ago a digital sequencer was something that cost $1000. Today you can go out and JL: Well, what you've done has certainly affected buy a digital sequencer with ADSR capabilities, and the daily lives of Polyphony readers. Thank you for a whole bunch of other things, at K-Mart. That's the interview. Ij just 10 years. Who knows what the next ten years P.S. to Polyphony readers: This is my third || are going to bring? Nobody ten years ago would interview now, and I'd like to know who you would S have said that you could buy a digital sequencer at like to see profiled. After all, this is your 1 K-Mart, made by a Japanese company that's turning magazine and I want to satisfy your needs. My ft out a half-million of them. mailing address is 8 Tyler St., Norwell, MA 02061.ft |

POUPHONy January/February 1982 13 r ON LOCATION DENTON, TEXAS The 1981 International Computer Music Conference

by Don Wilson Megabytes capacity, and a high­ are of as much interest to some as The L981 International Compu­ speed audio signal processor. are the compositions. While com­ ter Music Conference was held in This audio system appears to be puter generated sound is still in Denton, Texas, November 5-8. The quite powerful, fast, and flexible its infancy, some of the tape (or conference, hosted by the North with capabilities of recording, tape plus live) pieces played at Texas State University School of generation, modification, and the conference concerts displayed Music, was attended by approxi­ analysis of sound. excellent technique. It appears mately 300 composers, theorists, The conference concerts en­ that even though Stanford Univer­ engineers, programmers, and others compassed quite a variety of com­ sity and IRCAM are still the lead­ from all over the U.S. as well as positions and performances. There ers in computer generated sound several foreign countries. were pieces for tape, live instru­ research and technique, other com­ There were over 50 papers ments, tape and live instruments, puter music centers or studios are presented and six concerts, in­ tape and dancers, tape and slides, making a significant contribution cluding special performance of as well as one for live digital through new compositions. HPSCHD by John Cage and Lejareh synthesizer (performed by Jon Ap­ Concurrent with the confer­ Hiller. Cage also gave a lecture pleton). The dancers from NTSU ence papers were a concert gallery with slides, "Composition in Ret­ were exceptional. Compositions and exhibits. At the gallery, a rospect", as a part of another ranged from rather perceptually number of compositions were played concert. complex to minimalistic. A large with the order programmed random­ The general topics of the number of pieces employed compu­ ly. Some pieces had program notes papers were Compositional Ap­ ter-assisted compositional proces­ displayed on CRTs and another was proaches, Compositional Philoso­ ses . played through multiple speakers phy, Studio Reports, Computer- One different and entertain­ suspended from the ceiling. The Assisted Composition, Musical Data ing composition, Any Resemblance exhibitors included Alpha Centau- Structures, Computer-Assisted In­ is Purely Coincidental for piano ri, Casheab, Digital Keyboards, struction, Synthesis Hardware and and tape by Charles Dodge, had a Fairlight, and New England Digi­ Signal Processing, Real-Time Syn­ computer-synthesized operatic tal. These companies represent thesis, Psychoacoustics and Sound voice based on an old acoustic the major commercial digital syn­ Analysis, Computer-Assisted Analy­ recording of "Vesti la Giubba" thesizers currently available. sis, and Music Notation and Print­ from Leoncavallo's I_ Pagliacci. This conference did not seem ing. Tutorials were also given at The essential ingredient of the to have the excitement of so much the beginning of the conference piece, the interaction between the being new, or the camaraderie of a for those with little or no ex­ live performer and the tape, was small exclusive group of the ear­ perience in computer music. quite obvious and at times humor­ lier conferences; however, it was When Computer Music Confer­ ous. "...a computer-synthesized well worth attending. The papers ences began in the mid-seventies, voice searches for an accompani­ and pieces were generally better the most innovative work seemed to ment: with the original orches­ and more accessible than in the be emanating from universities; tration, with the (live) piano, past. The conference was well however, some of the most inter­ with copies of itself and with organized and the NTSU facilities esting work presented at the 1981 other computer sounds." were outstanding. As a bonus, conference came from commercial There was a noticeable lack without computer assistance, the groups. Of particular interest of compositions realized by hybrid renowned NTSU One O'clock Jazz Lab was the Lucasfilm Ltd. (maker of systems (computer controlled ana­ Band presented a special, hour "Star Wars") Audio Signal Proces­ log modules). The outstanding long concert for the ICMC con­ sing Station presented by Andy exception was Colors by Wayne ferees . Moorer, John Snell, and Curtis Slawson. Colors is a set of vari­ The 1982 International Compu­ Abbot - three of the better minds ations based on a structure of ter Music Conference will be held, in computer music. sound colors with many of the for the first time in Europe, in The Lucasfilm digital audio "colors" being speech-like. It Venice, Italy. Tentative plans signal processor-synthesizer, now seems natural that a composer are to charter a plane from the US being built, is intended for use using a hybrid system would con­ to Italy. If you wish to attend, in film sound and music proces­ centrate on an analog module that watch for announcements in Poly­ sing. The processor sub-units is rather different from its digi­ phony, the "Computer Music As­ consist of a controlling computer tal correspondent - the filter. sociation Newsletter" (PO Box with a high-resolution graphics Since the composer has per­ 1634, San Francisco, CA 94101), terminal, a real-time digital con­ formance responsibilities for a and/or the Computer Music Journal sole that is software reconfigura- tape realization, the performance (MIT Press, 28 Carleton Street, ble, disk storage with around 300 and the computer generated timbres Cambridge, MA 02142). ^

14 POUPHONy------January/February 1982 i M m m -- ..... Here's a simple test fixture to check for con­ have more than one type of male connector on your tinuity and short circuits in cables. The circuit cables, you can hook up multiple female connectors is a basic continuity tester made up of battery Bl, in parallel (both signal and ground connections) for LED Dl, and current limiting resistor RI. J 1 and J2. Construction. The circuit is non-critical and Using the tester. Position 1 of SI checks for very easy to build. Make sure you hook up the short circuits; the ground at J1 connects to the connections to SI correctly, that Dl is oriented signal line of J2, while D2 blocks voltage to J2's properly, and that the jacks are mounted on an ground in this position. If the LED lights when you insulated surface (plastic, bakelite, etc.). If you press S2, the cable has a short. Position 2 checks for con­ tinuity of the ground path. If the LED lights when you press S2, J2 | the ground is okay. Position 3 checks for con­ tinuity of the signal path. If the LED lights when you press S2, the signal line is okay. That’s it for the simple cable tester, I hope you find it useful. Parts list RI 470 Ohm resistor Dl Red LED D2 1N4001 or equivalent diode Jl, J2 1/4” phone jack - see text SI 2 pole, 3 position rotary switch S2 SPST pushbutton switch

by Richard Sloan ft's n 1 Here's a circuit I use to help repair amps and power sup­ plies. Figure 1 shows the basic circuit; it consists of hooking a regular light bulb in series with one side of the power cable. If tpe unit under test is shorted (in the power section), it will turn on the light rather than blowing a fuse. One can also work on the equipment while power is on to help locate the shorts, as well as test repaired equipment using this trick. Generally, for medium size power amps a 75 Watt light bulb works well. For larger amps, the bulb wattage should be increased. This setup can also indicate the relative amount of current demand by the unit under test; interpret­ It's not just a guitar tuner even though it works just great with any type of ing this reading correctly, how­ guitar. The fact is, that you can use Instratune 1000 with any type of ever, requires a little experi- musical instrument or electronic sound generator. HMR’s new Instratune 1000 is so versatile that it is considered by many to be a piece of precision test equipment rather than an ordinary tuner. With quartz crystal accuracy, Instratune 1000 generates 96 notes in eight octaves. The large 20 LED, 3 color dot graph tuning display is so easy to read, you can even tune up from across a room. Instratune 1000 also lets you hear every note on a built in speaker. Pickup is made by the internal micro ­ phone or a rear panel jack. A unique feature allows band members to tune up to a keyboard or an organ. Drop us a note and we will be glad to send you all the details. HMR, ^CP_Division, P.O. Box 204, West Newton, PA 15089.

-January/February 1982 15 /"PRACTICAL CIRCUITRY

We're starting to accumulate "All right, I'm sold", you a pretty good collection of syn­ say - "Let's get cooking!". I'm thesizer circuits here in "Practi­ with you - but wait a second while cal Circuitry". In fact, I hope I justify still further the title to present enough plans over the of this article. As I said, this next year to allow you to build a chip has a lot of features; but complete synthesizer. So far, that doesn't mean we have to use we've covered the noise source, them all. So in this design, I'm LFO, and sample-and-hold (all part going to strip down, streamline, of the SuperController module), and sometimes ignore various fea­ and a fairly elaborate dual VCO tures of the CEM-3330. What's module. Now it's time to start left is a terrific, low noise, and thinking about amplitude modula­ simple to build VCA. tion, hence this month's dual VCA The audio signal path. (and a companion dual ADSR, which Figure 1 shows the schematic. we'll cover next month). The dual Since this is a dual unit, I'll VCA and dual ADSR fit conveniently only describe one half (the other behind a 19" by 3.5" rack panel; half is identical, except that the if you wish to use the same con­ power supply connections are R14 56k struction technique, you may want shared by both halves). The audio to wait until next issue before input enters through J 2; Si you start building. I think chooses either AC coupling (for you'll find that a dual VCA/dual audio processing) or DC coupling ADSR module makes for a pretty (for processing control voltages). sharp combination. If the audio signal were not cen­ Now, about that title. The tered about ground (i.e. if it had name of the game is "think sim­ a DC offset), you would hear a ple", since VCAs can get pretty terrific "thump" every time you wild in a hurry. For example, the opened the VCA quickly. We can VCAs used in a dbx unit, or for certainly do without that, and automated mixdown, can get very that's the purpose of putting C7 complicated. This is because such into the circuit. To further applications demand very wide reduce thumping, trimpot R17 al­ range, low noise, and accurate lows you to trim out any residual tracking. However, for electronic offset in the chip itself. To set music it isn't necessary to go this trimmer, repeatedly hit some that far. You know the old saw fast envelopes and adjust R17 for A Audio R7 56k about the human ear being rela­ minimum thumping in the audio tively insensitive to amplitude output. variations as opposed to frequency R19 is an attenuator that changes? Well, it's true. So we pares the signal down to size as can cast out accurate tracking as needed. This design follows a being of rather minor importance standard that I have been using to us. However, we would like a for some time now, namely +5V fairly wide dynamic range, and audio signal levels and OV to +5V this also implies that we would control signals. With R19 wide like low noise as well. Finally, open, the VCA accepts +5V audio we want something that won't cost signals. us an arm and a leg (remember, Now for a few words about Dl, we're going to- build dual units). R5, and C5. Ordinarily pin 4 I think there's a good solu­ should remain at a voltage some­ tion to the above requirements: what below 0.7V. If that voltage the CEM-3330. If you're not fami­ were to rise above this level, liar with this chip, let me tell latch-up and possible damage to you about it. The CEM-3330 is a the chip would ensue. Dl makes dual VCA designed specifically for sure this never happens by clamp­ electronic music. It has "stan­ ing pin 4 to a maximum of 0.7V (a dard" input and output structures, diode drop). R5 and C5 form a is easy to apply, offers linear or compensation network. Their job exponential response and a choice is to help Cl (the actual compen­ of class A, B, or AB operation, sation capacitor) keep the ampli­ and best of all, it's relatively fier from breaking into supersonic inexpensive - about $8. If all oscillation. this sounds good to you, be sure For you "theory" buffs, this to check out the spec sheet to get VCA is a current in, current out, a real idea of the power of this current controlled amplifier. R8 chip.

16 POLUPHONU January/February 1982 VCAS:THIIMK SIM PLE

B CV Input

Continued on page 27 —m THOMAS HENRY. POUPHONy January/February 1982 17 POLYMART SCIENCE

The physical and psycho-acoustical background to music is an important part of musical synthesis. Helmhotz's Sensations of Tone is, a century after its publication, still the standard text for physiological acoustics. Psychology of Music by Carl Seashore, developer of the Seashore Music Test, provides an in-depth analysis of musical style and performance characteristics of many instruments. Music, Physics, and Engineering by Harry Olson, who worked on the first RCA synthesizer, is a thorough discussion of the physical properties and design of traditional musical instruments (plus a chapter on electronic music). Music, Sound and Sensation by Winckel is much like the Helmholtz work, with a bit less detail and more concentration on psycho-acoustics. #SEI\iS On The Sensation Of Tone $7.50 #PSYCH Psychology of Music $5.00 #MPE Music, Physics & Engineering $6.00 #MSS Music, Sound and Sensation $3.50

TECHNIQUE Synthesists must be well versed in a number of techniques and principles. "How to" and proiect oriented books are a great way to pick up these skills easily. How to Make Electronic Music by Drake, Herder and Modugno is a standard introductory text for music systhesis classes, with chapters on equipment, tape technique, composition projects, and more. Multitrack Primer by Teac is a step-by-step guide to building, outfitting, and operating your home studio. The Byte book of Computer Music describes computer control of electro-mechanical instruments, Fourier analysis, circuits and loads of software. Home Recording For Musicians is the original guide to outfitting and operating a budget studio for maximum results, including mixer and audio processing circuits and a demo recording. #HMEM How to Make Electronic Music $3.95 #TEAC Multi-Track Primer $4.95 #BYTE Byte Book of Computer Music $10.00 #HRFM Home Recording $9.95

ELECTRONICS Electronic cookbooks are a great way to stock your library with materials that are not only heavy on theory, definitions, and educational material, but chock full of practical applications as well! These books can easily replace stacks of manufacturers data sheets and applications notes all in an easy to use reference. Walt Jung's Op-Amp and Don Lancaster's Active Filter books are self-explanatory — required reading for synthesists! Audio Op-Amp is an edited version of QACB, containing only audio applications. Lancaster's CMOS book is much more than a digital reference — phase lock loops, top octave generators, touch switches, and other things you need! Electronic Projects discusses electronic construction technique for the novice and provides 27 projects with PC patterns and a demo recording of the effects. #OACB Op-Amp Cookbook $ 15.95 #CMCB CMOS Cookbook $ 12.95 #AFCB Active Filter Cookbook $14.95 #EPFM Electronic Projects 2nd edition $14.95 #AUOA Audio Op-Amp Applications $8.95

REFERENCE Often used reference materials to answer the many questions encountered in everyday synthesis!?)... The Source is over 125 pages of patches in universal flow chart notation; the largest publication of its type. Audio Cyclopedia has 1760 pages with 3650 entries and hundreds of drawings and schematics to answer any questions about audio Polyphony Binders hold up to 12 issues of any 8 V2" x 11" publication without punching holes; keeps issues like new for unending service. Electronic Music Synthesizers devotes the first half of features and functions of commercial equipment (Moog, Arp, Paia, Oberheim, EML, and RMI); the second section provides schematics and projects for the experimenter. #SOURCE The Source $4.00 #CYCLO Audio Cyclopedia $44.95 #EMS Music Synthesizers $6.95 #BIND Binders $4.95

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4/8 Track Studio Log Book provides a place to keep all the important information on your tape library. Log in timing, type of tape used, record patches, make notes and use the expanded track sheet to list sequential changes in tape tracks relating to the settings of the index counter. Craig Anderton's Contemporary Keyboard Articles is a reprint \ of all the articles from June 1977 through February 1981, covers tips, technique, theory, maintenance, and numerous construction projects. Device Back Issues — during the year that this newsletter was published, it featured almost 200 pages of technical information for the guitarist/musician. A wealth of articles on; design, product reviews, and modification and construction projects. Sold in complete set, individual issues not available. Limited number available, order yours now. #SLB Studio Log Book $4.95 #AA Craig Anderton's Keyboard Articles $5.95 #DEVICE Complete set (12) Device Back Issues $18.00

RECORDINGS #C Q R O S Cords - Synergy $ 7 .9 5 #ER R O Electronic Realizations - Synergy $ 7 .9 5 # S E O U Sequencer - Synergy $ 7 .9 5 # G A M E S Games - Synergy $ 7 .9 5 # E L E M Elements - Mychael Danna $ 6 .9 5 # C A M T Craig Anderton Music Tape $ 5 .9 5 # A R P T Music For Airports - Brian Eno $ 7 .9 5 #D E LTA Rainbow Delta - Pat Gleeson $ 7 .9 5

18 POUPHOMy January/February 1982 NEW LISTINGS FROM POLYMARTi BACK ISSUES' HOW TO DESIGN, BUILD,& TEST COMPLETE SPEAKER SYSTEMS The wide variety of practical applications and by David B. Weems construction projects in past issues makes a binder full A complete Do-It-Yourself guide for audio buffs who want the ultimate in of POLYPHONYs a frequently used reference to keep near sound quality. EVERYTHING about your synthesizer , home studio or workbench. Most back speakers, with charts and diagrams to issues are still available for $2.50 each postpaid. Check help you develope the ABSOLUTE sound system. the issues you wish to order on this coupon and add the *CSS...... $7.95 total to your POLYMART order.(other side), or order by HOW TO BUILD A SMALL BUDGET RECORDING STUDIO FROM SCRATCH volume and issue number (0304,0402, etc.) on the POLYMART by F. Alton Everest order form. Details of design, construction and treatment of twelve actual studio suites are included. Acoustical principles are #0101: 1975: SOLD OUT #0201: 1/76: SOLD OUT elucidated along the way in the context #0202: 2/7*.? SOLD OUT #0203: 3/76: SOLD OUT of real life projects and problems. Everything you need to design, build, and operate your own recording studio! I I #0204: 4/76: music notation - timing, external inputs for #BRS...... $9.95 Gnome, Programmable Drums, Equally Tempered D/A, low cost AR project, digitally encoding keyboards, patches, Volume 1 & 2 index. POLYMART is provided to help Polyphony readers find the [_J #0301: # 7/77: frequency divider project, random tone special supplies their projects require. The items we stock are generator project, normalizing synthesizer controls, eliminating patch cords, computer control of analog modules, Chord Egg a must for every active music experimenter’s lab or studio modification, adding pitch bending, patches. bookshelf. Not all of PolyMart’s offerings are shown in each #0302: 11/77: The Sensuous Envelope Follower, digital _ es, LED wall art, build a bionic sax, data to music peripheral issue. Refer to back issues if you don’t see what you want. Your Rproject, Apple II as a music controller, using the NE566 as a VCO, suggestions for additional items are welcomed. patches. I ,1 #0303: 2/78: computer controled Gnome, using joysticks, TO ORDER: Tear out this half page order blank; note that there is build a bionic trumpet, ultra-VCO modifications, voltage control the Mu-Tron Bi-Phase, oral joystick, patches. a back issue list on the other side. We cannot invoice; payment #0304: April/May 78: Minimoog modifications, non-keyboard must be enclosed with your order. To help defray shipping and moduqTule use, phasing and flanging (theory and circuits), memory expansion for programmable drums, digitally addressed transposer packaging costs, there is a flat $.50 handling fee per order plus project, polyphonic software (with software transient generators), patches, volume 3 index. payment of postage costs. MasterCharge and Visa are I I #0401: July/August 78: analog delay lines (theory and welcome, but there is a $10.00 minimum on charge orders. projects), composing for electronic music, note to frequency (and visa versa) cpnversions, build a trigger delay, software for Foreign orders must be paid by certified check or money order computer composition, low cost VCO circuit, patches. in U.S. $ drawn on a U.S. bank (or by charge card) . Phone orders #0402: Sept/Oct 78: electronic music notation, notes on recording of "Cords" by Larry Fast, sequencer software - part are welcomed for charge card orders only. Bone, rhythmic control of analog sequencers, touch switch projects, modular vocoder techniques, PET as a music controller, patches. Name: ______#0403: November/December 78: SOLD OUT Address: ______!______I 1 #0404: January/March 79: add-ons for vocal F and V converter, shorthand patch notation, more on note to frequency conversion, graphic monitor project, George Russell, super VCA circuit, echo software, Vol. 4 index. City __ State Zip __ #0501: May/June 79: SOLD OUT Card #_ I I #0502: July/August 79: hex VCA/mixer project, electronic music schools and studios, modify the Oberheim Expander Module, MasterCharge Bank # Expiration Date profile of Ernest Garthwaite, budget microphones, digitizer projects and software, bar graph ICs. Signature______#0503: Sentember/October 79: Quantity Item Price #0504: November/December 79: SOLD OUT ___ #0505: January/February 80: Joseph Byrd, Mort Garson, □Larry Fast on 'Games', composing for 'live plus tape', using the CA3280, recording vocals, ADSR circuits. j #0506: March/April 80: Computers in Music: real time audio processing hardware, Powell sequencer system, Max Mathews, advanced STG software, PortaStudio, phase modulation, Volume 5 index. #0601: May/June 80: SOLD OUT ___□ #0602: July/August 80: Peter Gabriel, digital VCO project, dream modules, optimum level settings, dynamic phrasing, patches. | 1 #0603: Sept/Oct combined with Nov/Dec 80: alternate controllers, add voices to Casio M-10, voltage controlled quadrature oscillator project, cordless patch bay, recording rules, patches. _# of items Sub Total Q #0604:i: January/February 81: Special Construction Edition; Build: AudicLo Circuit Breaker, Pulse Width Multiplier, Magnetic ------Shipping Charges ------Handling -5Q_ Harp, 50 Watt/Channel Stereo Power Amp, Quad Sequential Switch, POD Mods, patches. U.S.:add 10°/oof SubTotal or $5.°°maximum □__ #0605: March/April 81: Portable Music Issue, reviews of Remco's FX, E-H Mini-synthesizer, Casio's VL-Tone, plus mods for Foreign: 20°/o of SubTotal the M-10, GR-500, mini-amp, and the Korg X-911. Introducing; Shipping Practical Circuitry and On Location, new columns. or $10P°maximum #0606: May/June 81: Synthesizer: Hardware Mods and tware. Modular Synthesizer Effects, Environmental music. -n SUBSCRIPTION o- KeyboardS assignment for the 8700, new columns; Details, Practical Circuitry,Circ and On Location. Volume 6 index. U.S. S1B/YR. S22/2YRS. FOREIGN S14/YB. S26/YR . ___ #0701: July/August: Guitar Electronics: Modify: Fender Amp,□ MXR Phase 100, GR-500. Input/Output Structures, $5 Analog Programmer, Sample and Hold technique, Modular Synthesizer Effects, new column: Applied Synthesis, Marketing Your Records. Back Issues (from other side). #0702: Sept./Oct.'81: Harald Bode Interview, Live Plus Tape □ New Technique, Xenharmonics, Kraftwerk Live - Review, Total Enclosed. Psycho-Acoustic Experiments, Practical Circuitry - Super Controller, Applied synthesis - Brass, Construction Tips For Beginners. Return This Half Page

1 I #0703: Nov./Dec.'81: Dave Rossum interview, Applied Synthesis: Strings,Details: Series-parallel/Sum-Difference. The mmmm To: POLYMART VISA Sound Gizmo and Pro-One Reviews, Practical Circuitry: VCO Deluxe. P.O. Box 20305 fiH Oklahoma City, OK 73156 POUPHONy January/February 1982 19 Tell Them You Saw It In Polyphony ’

.. Fast CMOS. CMOS logic has are directly proportional to an long been popular due to its low external clock frequency within an current consumption and non-cri- accuracy of 0.6%. External resis­ tical design qualities; however, tors determine gain and Q. Avail­ it will not operate as fast as TTL able responses include allpass, or LSTTL logic. Now Motorola lowpass, highpass, bandpass, and (3501 Ed Bluestein Blvd., Austin, notch up to 20 kHz with a Q as TX 78521) has introduced the high as 500. Price is $3.70 in MC54/74HCXX series, which are quantities of 100 up. claimed to accept 25 MHz clock speeds. Initial offerings include popular counters and gates, with additional logic devices scheduled for introduction this year.

FOR A COMPLETE SET OF DATA SHEETS ON THE COMPREHENSIVE Microphone news. For a copy LINE OF SERGE SYNTHESIZER of Audio-Technica's new 24 page MODULES SEND $3 TO: catalog, listing electret and dy­ namic types, accessories, and Serge Modular Music Systems 572 Haight Street more, write to Aud io-Technica San Francisco, CA 94117 U.S., Inc., 1221 Commerce Drive, (415) 621-6898 Stow, OH 44224.

Con Brio announces Score- writer System Option for the ADS 200. The Scorewriter system prints keyboard performances, de­ rived using the Con Brio's music programming capabilities, on paper in conventional music notation. Con Brio, 975 San Pasqual St., Suite 313, Pasadena, CA 91106.

New Serge. Serge Modular Music Systems, 572 Haight St., San Francisco, CA 94117 has intro­ TASCAM from TEAC (7733 Tele­ duced a "Divide-by-N Comparator" graph Road, Montebello, CA 90640) module. In addition to normal has announced the PE-250, a moving comparator functions, there is a coil cardioid microphone that has voltage-controllable divide by 2 the ability to handle high tran­ to 32 function suitable for pro­ By: Diane Sward Rapaport sient spikes without overloading cessing audio or control signals. or distortion. Equipped with XLR Kit price, $140; $170 assembled. THE COMPLETE GUIDE connectors, the PE-250 lists for $250.00. S h h h h h . Micmix (2995 TO INDEPENDENT Ladybird Lane, Dallas, TX 75220) CMOS active filter. National has introduced the Dynafex single- RECORDING Semiconductor has announced the ended noise reduction system. MF10, a low cost, monolithic, CMOS Controls include a threshold NOW AVAILABLE THROUGH active filter that can perform a control that determines at what POLYMART wide variety of functions and level maximum noise reduction Use order form on page 19 requires no external capacitors occurs, and a hard-wired bypass for operation. Center frequencies switch.« ^M ASR...... $11.95

20 POUPHQNy January/February 1982 m o o u U y u o e

i, * ttrrtatuoes

PHRASE P=§=..._ ^ _

Anderson/Giorno/Burroughs You're his bass through a 360 Systems/- Glass lies Gavin Bryars. Piano, the Guy I Want to Share My Money Oberheim interface, and Norman vibraphone, marimba, and orches­ W i t h (Giorno Poetry Systems Durkee plays some very tasteful tral percussion play four 020/021). One-third of this 2- keyboard synthesizer, but the tune/non-tune homages to, in or­ record set is some of the previous electronics definitely serve the der, Bill Evans, Gustav Holst, work leading up to Laurie Ander­ music rather than vice versa. Ferruccio Busoni, and Percy Grain­ son's single, "Walk the Dog", ger. reviewed July/August 81. Although Conrad Schnitzler Con 3 (Sky Eugene Bowen Bourgeois Magnetic not as tight as the single, it's 061) and Control (DYS 04). After (Cantil 281, E.P.). Side 1 takes still interesting for that reason. a decade of near-total silence, the drifting piano of Harold Budd Another third is John Giorno's the founder of both Tangerine Dream and Cluster seems to be and overdubs some synthesizer and poetry, shouted like a radio evan­ African percussion - an intriguing gelist and over-dubbed from three making up for lost time. Unfor­ concept. separate performances. The last tunately, not everything that he third is sleepy storytelling from touches turns to gold. Con 3 Magic Dragon Emotional Landscape William S. Burroughs, which relies contains marginal vocals backed by (Panik PFRQQII) Magic Dragon is a equally on humorous inflection and electronic patterns and surpris­ German band now living in Canada, the shock value of swear words. ingly normal drums. The electron­ and four of the five tracks are in How do you divide four sides three ic patterns on Consequenz (re­ a popular German rock style: gui­ ways? The fourth side has three viewed May/June 81) were better. tar, bass, string machine, and sets of grooves which run concur­ Control consists of random voltage early Pink Floyd vocals. The last rently - it's mere chance which generators into a variety of track collages preachers over a one you'll get each time. patches. Not much beyond the ponderous synthesizer phrase - noises to hold your attention. very dark and scary. Cluster Curiosum (Sky 063). The direct opposite of their last, Roedelius Wenn der Sudwind Weht Basement 5 In Dub (Island 2038). Curiosum returns to simple musical (Sky 064). Roedelius, who like Dub is one of the most interesting patterns and complex patches. For Liberace has lost his first name, developments to come out of reg­ my money it's good to have the returns to his Farfisa for another gae, where the multi-track backing boys home. album of spacey carnival music. tracks of a song are echoed, re- verbed, and mixed in and out for Laurie Spiegel The Expanding Uni­ Wrinklemuzik A Move to the an outlandish new composition. verse (Philo 9003). Computerized Right/Bangkok/Rein (Exit 1201). Basement 5 apply the same tech­ drone music, warmer and more human A 33-rpm 7" single by Kenn Lowy, nique to their w a 11-of-sound than usual. using E-Bow guitar, rhythm box and English protest music, which owes the Public Access Synthesizer Stu­ more to the Sex Pistols than King The Scientific Americans Taking dio in NYC. Side 1 contains two Tubby. Time/Call Home/Service with a pleasant rock tunes, side 2 an Smile (Techno Tunes LES 30). A introspective mood piece for Frip- Tom Tom Club Tom Tom Club (Sire 9-inch, 3-tune, 1-sided flexi- pish guitar. A good effort. 3628). After publicly lambasting disc, featuring electronic percus­ leader David Byrne for acting sion, with guitar, bass, drums, Harold Budd The Serpent (In "like a 14-year old", Talking and vocals. Eno and Talking Heads Quicksilver) (Cantil 181, E.P.). Heads members Tina Weymouth and influenced rock that is progres­ Harold Budd plays dream sound­ husband Chris Frantz have used the sive in the best sense - I give it tracks on undamped electric and same studio, the same engineers, an 85. acoustic pianos. They're not so and the same back-up musicians for much tunes as resonance studies. their solo debut. It sounds a lot Collier & Dean Whistling Midgets like "Remain in Light" without (Inner City 1126). Tom Collier Gavin Bryars H o m m a g e s (Crepus- Byrne's paranoid lyrics and voice plays vibes and marimba, and Dan cule 027). Somewhere between the - replaced rather insipidly by Dean plays bass guitar, and this dreamola piano of Harold Budd and Tina and two sisters. Only the is a jazz album. Dan also runs the engineered tedium of Phil ...... continued on page 32

POUPHONU January/February 1982 21 n m w T f f The S to ry of G ozinda This month's column will re­ visit the "Gozinda-Gozouta" bal­ I ance d / unb a 1 anced , input/output structures (first mentioned in the July/August 1981 issue of Poly­ phony) by presenting a complete, do-it-yourself Gozinda/Gozouta board that you can add to your own projects. But first... The title of this column is "Details" because it is the funda­ mental details that make or break quality design work. I am a de­ tail fanatic, and it has paid off over and over again during my many years of design work. Inattention to details is responsible for almost all good circuits that have found themselves needlessly float­ ing in the toilet. Confession time. I have fallen victim to the exact problem that I preach against - namely, inattention to detail. In the Gozinda/Gozouta column, I stated that the input impedance seen by Vin (-) was R2 (see figure 1). Not so. 11 is 2/ 3 R2. This makes a big dif­ ference when it comes to keeping balanced lines balanced! The cor­ rect value for resistors RI and R2 is 30k Ohms (30.1k Ohms being the closest 1% value), not 20k Ohms as this part of the circuit as an I think an example is the shown in the Jul/Aug issue. inverting amplifier whose input best way to understand why the The trap I fell into is a impedance would indeed have been impedance is 2/3 R2. Assume there mis-app1ication of something equal to R2. However, looked at is +1V at the tip and -IV at the called the "rule, of superposition" correctly, it is seen that the ring of the input jack. That is, used extensively in circuit analy­ voltage at the intersection of therefore, +1/2V at the plus input sis. Superposition allows you to resistors RI and R2 is the same as port of the op amp. And the minus look at one piece of circuit at a the voltage induced by the posi­ port. The ring input current will time and then combine the results tive driving line (tip) at the be equal to the voltage across in the end for the final answer. intersection of resistors R4 and resistor R2, divided by R2. This But it must be used correctly, or R3a. That is, the voltage at the voltage equals +1/2V - (-1V), or you wind up lying to yourself. plus input equals the voltage at 3/2 Volts. The current is then 3 Like I did. the minus input. It has to; that divided by 2 R2. The ring input I treated the negative input is what an op amp is all about - impedance is, by definition, the impedance by looking at that port the output will do whatever is input voltage (-1V) divided by the only, out-of-context to what the necessary in order to make the two input current (-3 divided by 2 R2, positive input was doing at the input voltages equal. It is with the minus sign indicating same moment. That means I treated called a servo loop. current flowing out of the cir­ cuit), giving an answer of 2/3 R2. Simple...if you pay attention to details. The new rules are that RI = R2, R3 = R4, and R2 = 3 R4 for perfectly balanced line input im-' pedances. Each leg will "see" an impedance equal to R3 + R4. There, I've confessed. Now let's move along to the G/G-l, a complete Gozinda/Gozouta sub- module with all the required em­ bellishments for any of your D. I. Y. projects. With the G/G-l, you don't have to worry about signal conditioning of the inputs or outputs; you can jump right into

22 POUPHONU January/February 1982 & Gozouta Revisited by Dennis Bolm project's main circuit board. The G/G-l now provides the input for the device. • Run another twisted pair of wires from the G/G-l PC board points marked "IN" and "GND" to the output of your new circuit and its ground point. The G/G-l now provides the output for the de­ vice. • Run a twisted triple group of wires from the G/G-l PC board points marked "V+", "V-", and "GND" to your power supply posi­ tive, negative, and ground points R11 100 respectively. • Important: Be sure the w v - © G/G-l input and output jacks are isolated from the chassis (if you buy the G/G-l kit this is guaran­ teed by the Switchcraft insulated In from jacks provided with the kit). circuit • Run a parallel 10 Ohm resistor and 0.01 uF capacitor from your power supply ground point to chassis ground. Applying the G/G-l: Modi­ fying existing equipment. This is a little more cbmplex, but it still isn't too hard to retrofit existing equipment with a Gozin- da/Gozouta board. • Remove the input jack and cut the hot wire; reconnect this hot wire to the G/G-l terminal marked "OUT". Cut the ground wire from this jack and reconnect it to the "GND" terminal on the G/G-l. • Remove the output jack and cut the hot wire; reconnect it to the G/G-l terminal marked "IN". Cut the ground wire from the old whatever goodies you want to Note that three poles are required jack and reconnect it to another build. Easy and inexpensive to since the ground must also be "GND" terminal on the G/G-l. build, you will find this a useful disconnected and bypassed; there­ • Run a twisted triple group circuit to have around. fore, the bypass mode gives a true of wires from the G/G-l PC board three wire bypass. points marked "V+", "V-", and Construction. The printed Calibrating the G/G-l. Apply "GND" to the power supply posi­ circuit board isn't required, but a 1 Volt, 1 KHz signal (or what­ tive, negative, and ground points it sure makes things easy by al­ ever kind of steady tone you have of the existing circuitry. lowing PC mounted phone jacks to handy) to the ring and tip of the • Install the G/G-l along be used. Mounting the jacks on input jack. An easy way to do with its input and output jacks. their 1" centers through a pair of this is to use an unwired male Important: When mounting the G/G- 3/8" holes also supports the PC stereo input jack with the shell 1, be sure to isolate the jacks board and all circuitry, making removed, then jumper the ring and from the chassis. things easier yet. tip together and apply signal to • Run a parallel 10 Ohm Using the NE5532 dual low- this point. Next, adjust the resistor and 0.01 uF capacitor noise IC provides superior noise trimpot for minimum signal at the from the existing power supply and slew performance. In addi­ output. ground point to the chassis. tion, it can drive 600 Ohms and Applying the G/G-l: New Pro­ long lines without getting upset, jects. I tried drawing some dia­ That should do it. For stu­ thus eliminating the need for any grams, but they got pretty messy dio equipment, rack mount gadgets, additional line drivers. pretty fast. Hopefully the fol­ or whatever, the G/G-l board lets Switch SW-1 is an optional lowing words will do the job. you have consistent, standardized bypass switch which can be added • Run a twisted pair of input/output structures that work when required. Holes are provided wires from the G/G-l PC board well with each other - as well as on the PC board for the switch, or points marked "OUT" and "GND" to with other pieces of equipment. for jumpers if it is not used. the input and ground point of your .continued on page 34

POUPHOM January/February 1982 23 JTTSIMPLE SQUARETTL. WAVE SHAPER % ® ® M M

produce quite a broad palette of serve the usual care in handling — VVi th everything going digital sonic variations from simple the CMOS IC and observe good wir­ these days, we're seeing a lot of square wave and pulse signals. ing practice. square wave audio signals, espe­ Anyone who has been annoyed by the The Simple Square Wave Shaper cially in toys and mini-synthesi­ voicing limitations of instruments (see figure 1), or SSWS for short, zers; after all, in the language using a top octave generator as a is designed to accept an input of digital technology a square tone source may see these devices square wave that swings from wave is a series of Is and Os of in a different light when proces­ ground to more than about +8V. equal duration and is very easy to sed with this circuit. The Bionic This means that you can drive it generate. Of course, digital Sax and Bionic Trumpet (Nov '77 directly from binary dividers, techniques can also produce more and Feb '78 issues of Polyphony, CMOS logic outputs, and the like. complex sounds. In a sophisti­ respectively) are particularly For processing lower level signals cated digital tone generator, the suitable as inputs to this device, or signals that are symmetrical action still begins with a square because they are only designed to about ground, add the comparator wave - running at a very high output one note at a time - you'll input stage shown in figure 2. In frequency - which clocks out a even be able to get some pretty fact, for the most universal box complex waveform previously stored decent approximations of sax and possible, it might be a good idea in memory. A D/A converter then trumpet voicings for the first to include this input conditioning converts this data into an analog time with these instruments, along stage whether you anticipate need­ waveform, with one complete cycle with many other voicings. Playing ing it or not. through memory resulting in one more than one note at a time pro­ The portion of the circuitry cycle of the final waveform. With duces iffy results, but can work in the box is optional; it is microprocessor control the synthe- in some specialized cases. This necessary only if you plan to pro­ sist can program literally any circuit will also do wonders for cess the outputs of tone genera-

r-J-J \ ,|_[lC2aY

R8 10k O ....A A A /....^ input

D3 '' [i C 2 — •] XN914 RIO output 100 ^each NAND gate 1/4 CD4011 or CD4093 Figure 1 Note: Power supply connections to op amp assumed, +5V to +15V DC

conceivable waveform into memory, any PWM output of a standard VCO. tors which have 50% duty cycle clock out the waveform at the Perhaps the ideal input for this square wave outputs. If you plan desired frequency with a VCO, and device, however, is Craig Ander- to use this module only for pro­ even use various techniques to ton's outstanding "Pulse Width cessing a modulated pulse wave­ modify the waveform in real time. Multiplier" circuit, which ap­ form, this portion of the circuit For those of you interested in peared in the Jan/Feb '81 issue of can be eliminated. The purpose of learning more about the techniques Polyphony. Not only will you be IC2a and IC2b is simply to assure of digital tone generation, Tony able to produce complex modulated that the amplitude of the signal Lewis' Digital VCO construction pulse waveforms from a standard is equal for both settings of SI, article in the Jul/Aug 1980 issue VCO, but you will be able to shape while preserving phase integrity. of Polyphony is highly recom­ the pulses into variations of The circuit built around IC2c and mended . sawtooth waveforms, and these new IC2d extracts a narrow pulse from An analog waveshaper. While variations will still be subject a straight square wave signal. the wave shaper presented here is to the modulation! The next portion of the cir­ not as elegant as the ones men­ How it works. The circuit is cuit will look familiar to anyone tioned above, it will nevertheless simple to put together; just ob- who has built simple transient

24 POUPHONU January/February 1982 generators. It is exactly the harmonic content of the signal. trolled version are invited to dig same kind of lag-processing type Conversely, advancing the "D" con­ in - just remember to share your of circuit used in transient gen­ trol will cause the descending results with Polyphony! erators, except that the values of excursion of the waveform to ramp, Conclusion. Until reasona­ RI, R2, and Cl are selected for while leaving the ascending por­ bly priced programmable tone gen­ the audio range (note that this tion intact. Advancing both con­ erators with musician-oriented same circuit can process square trols will produce variations be­ controls reach the market (hope­ wave modulation signals by chang­ tween square, triangle, and skew fully in kit form), we're just ing Cl to 1 uF and changing RI and (trapezoidal) type waveforms. going to have to use our imagina­ R2 to a value of 500k or 1 Meg). With a narrow pulse input only a tions and ingenuity to provide The wave shaper works by selec­ small part of the rotation of the some readily accessible means of tively filtering the ascending (A) "A" control is useful, but rotat­ producing the complex timbral excursion of the waveform and/or ing the "D" control will produce structures that creative synthesis the descending (D) excursion of variations between a pulse and a demands. Besides, even sophisti­ the waveform present at its input; sawtooth. Of course, if the input cated digital tone generators may that's really all there is to it. is a modulated pulse the results benefit from established analog How to use i t . The effect of can become impossible to describe filtering techniques and outboard this module on various signals is in the standard terminology of VCO wave-shapers along the lines of quite different from that of a oscillations. the one presented here. It's too conventional filter, so it's best Despite this module's useful­ early to tell for sure just yet, to think of it strictly as a wave ness, there are some limitations but I prefer to think of analog shaper. With SI in the "normal" since the device is frequency de­ and digital as having a both/and position the waveform at the out­ pendent (in other words, it will relationship with music synthesis put will depend on the duty cycle not produce consistent results in the future, rather than it and frequency of the incoming over a very wide range, but should being a choice between one or the signal, and on the position of the be restricted to a few octaves for other. In any case, I do know A and D controls. With the con­ a given setting of the "A" and "D" that it is the will of the crea­

trols set at minimum resistance, controls). Ideally RI and R2 tive musician, more than any other

the signal will pass virtually should be voltage controlled re­ single element, that is most res­ unaffected (this, combined with sistors so that at higher frequen­ ponsible for designing the future the unit's low noise, makes a cies their resistances become tools of the craft. Who knows bypass switch unnecessary). If smaller; I've been too busy to what new marvels will emerge from the input is a 50% duty cycle pursue this right now. Any read­ the embryo of our>dreams? square wave, advancing the "A" ers with some ideas and the neces­ control will delay the rise time sary ambition to turn this simple of the ascending excursion of the wave shaper into a voltage-con­ waveform, thereby affecting the -- # BY PROFESSIONAL DEMAND sensitivity DDC OFFERS FREE ADVICE, PERSONAL SERVICE R5 10k ' R6 10k power supply AND ONE DAY SHIPPING OF THE FINEST MUSIC r -A/y\>------w \ , — © positive AND SOUND EQUIPMENT AVAILABLE ANYWHERE: Note: Power supply 3 CrOULin iraynor connections to op amp assumed, to input, p,.! K0RG P o lls te r, +5V to +15V DC fig. 1 _! l I KELSEY iPIlffllfliffil C3 R7 10k q | | A / W T E A C ^ g w f ______input 0.1 uF Figure 2 (f\)© s f e O D i M a r ^ ' 1 ^ l|l REMO T7U=>CO M 0 YAMAHA C H UM A R

POUPHOM January/February 1982 25 PRACTICAL CIRCUITRY this node as we want). The full strength CV input ...... continued from page 17 feeds J3 and then R9. The value of this resistor is converts the input signal to a current, while the such that a OV to 5V input yields full off to unity output current is converted to a voltage via R7 and gain. This is the input that you would normally use Al. The output is then presented to Jl. Once with an ADSR. J4 is another control voltage input again, this circuit is set up to give a +5V output with an associated attenuator. You would use this signal under normal conditions. input most commonly for tremolo or amplitude modula­ The control signal structure. The exponential tion applications. R21 (linear tape) is an initial control, at pin 6, is not used in this circuit so we set pot, with wiper centered giving full off. This simply ground it. My reason for going with a linear pot can be used to manually open up the VCA, or to mode VCA is simple. Almost all ADSRs (including the offset any possible bias present in a control signal one I'll be presenting next issue) already put out applied to J4. an exponential control voltage. This being the C3 is a rather new development. If you have the spec sheet for the CEM-3330, you won't find C3 case, it makes sense to follow the ADSR with a

linear VCA since the end result will be an exponen­ mentioned anywhere. But if you are a subscriber to tial envelope anyway. This is perhaps the most Synthesource (Curtis Electromusic, 110 Highland "natural" envelope. However, suppose that we were Avenue, Los Gatos, CA 95030), you may remember a to follow the exponential ADSR with an exponential little note that was presented in the Winter 1981 responding VCA. The result would be "exponentiating issue, page 11, on how to stabilize the linear the exponential", an unusual envelope. So let's control input. This capacitor helps prevent spuri­ play it simple and ground pin 6. ous oscillations at low control currents. Well, that's it: VCAs the simple way! I have Pin 7 is the linear control input, which, un­ four of these VCAs in my system and love them. I

like pin 6, is at virtual ground (which in plain confess that VCAs are not exactly the most exciting language means that we can sum as many inputs into modules in a synthesizer, but if you have suffered through differential pairs, FETs, and CA3080s like I have in the past you will really appreciate the simplicity and reliable operation of this chip. Looking ahead. For a dual VCA/dual ADSR cir­ cuit, a good printed circuit board layout is impor­ tant, since stray capacitance can be troublesome. If you want to see how I implemented this dual module, stop back next issue when I present the ADSR and say a few things about construction,

Specifications Audio Input: AC/DC selectable +5 signal level 50k input impedance, with attenuator Control voltage: Full strength input, (0 to 5V), 50k impedance Initial set, from 0 to greater than unity gain PARTS LIST All resistors in Ohms; 1/4W; 5% preferred.

Thanks to your exceptional response, we're almost completely RI, R2 100 R15, R16 100k sold out of the parts listed in our Sept/Oct 1981 ad. So, R3 680 R17, R18 100k trimmer please - no more orders! However, we are currently scouring R4, R5 lk R19 - R24 100k pot our warehouse for other bargains that might appeal to the 10k R25, R26 150k Polyphony readership. We didn't have time to get an ad R6 together for this issue, but next issue we'll have some more R7 - R14 56k R27, R28 470k goodies for you...including rare high-voltage capacitors suitable for all you tube amp fans. All capacitors rated 15 VDC or higher.

Incidentally, these closeout ads are only appearing in Cl, C2 100 pF Polyphony. It's our way of saying thanks for your support C3, C4 .001 uF during our years in the parts business, and frankly, we get a better response out of you folks than we do from ads in C5, C6 .01 uF the other magazines. So, happy experimenting, and thanks C7, C8 .22 uF again. C9, CIO 33 uF, electrolytic

Bill Godbout Semiconduc tors Godbout Electronics Dl, D2 1N4148 or equivalent IC1 CEM-3330 IC2 4739 dual op amp

Mechanical parts

Jl - J8 Open circuit 1/4" phone jack SI, S2 SPST slide switch OAKLAND AIRPORT, CA 94614-0355 (415)562-0636 Misc. Knobs, wire, solder, hardware, etc. ^

26 POUPHONU------January/February 1982 Ad Index

upper notes to be a little more Blacet Music Research ...... 9 — Th i S i s the kind of project muted so that when you play in that almost appears to be too good these upper registers, you don't Bode Sound Company ...... 7 to be true - it's so simple there interfere with other instruments. Dickstein Distributing Co... 25 might be a tendency to dismiss it. Aside from a device like the SSWS, That would be a mistake. there is no simple way to dupli­ Godbout Electronics ...... 26 We tested the simple square cate this effect with conventional HMR ...... 15 wave shaper with a variety of synthesis equipment - setting a sound sources, and it worked well filter for weighted keyboard PAIA Electronics, Inc.. 27 & 36 in its intended application of tracking, for example, does not Phoenix Systems ...... 9 modifying the square and pulse even come close to imitating the waves emanating from synthesizer timbres produced by the SSWS. PGS Electronics ...... 31 VCOs and other square wave genera­ Our second surprise occurred Polymart ...... 18, 19 & 20 tors. The only inconvenience was when we tried the SSWS with two having to re-adjust the A and D guitar effects, the Mutron Octave SMS ...... 35 controls for different frequency Divider and the Ultra-Fuzz (pro­ ranges; however, the range of the ject #6 from the book "Electronic Sequential Circuits ...... 2 SSWS was greater than you would Projects for Musicians"). By pro­ Serge Modular Music ...... 20 expect. Having a D time greater cessing the octave lower output of than the period of the waveform the Mutron with the SSWS, we could TEAC Corp. of’America ...... 5 reduced the overall level, but achieve rich, bassy sawtooth waves caused no other problems. The A that sounded just great. The only control was, as stated in the problem was that Cl was a little text, of limited usefulness with small for these low frequency pulse waves but was extremely waves; we had better results with FXPFRIMFNT WITH effective when used with square a 0.02 uF mylar capacitor. Since wave inputs. While Bobby says this value also seems to work well EKx Series that the circuitry inside the dot­ with high frequency signals, you ted line is optional, we recommend might wish to just use a 0.02 uF EXPONENTIAL including it (as well as the input capacitor for Cl in the first MODULE CARDS conditioning stage shown in fig. place. 2) as part of the module for maxi­ The Ultra-Fuzz is basically a EKx 10 ADSR mum applicability to a variety of comparator circuit that produces a envelope generator with exponential control sound sources. square wave output from guitar, of Attack, Decay and Release times over a guaranteed .002 to 20 second range. No control There were two major sur­ voice, and the like. It only voltage feed-throuqh.. $24.95 plus $2 postage prises we encountered while test­ accepts one note at a time. If EKx 20 VCF ing the SSWS. First, the fact you like square waves, then it's with exponential control of pole frequency that the device is frequency de­ fine as is - but this little cir­ over a 10 octave range. Jumper programmable pendent may actually be an advan­ cuit really dresses up the basic for 24 dB/Oct. LP, HP, BP or All Pass response. output. With a little twiddling, Voltage controlled resonance. Low noise, 86 dB tage , not a disadvantage. Most below max. output. $26 .95 I$2,001 acoustic instruments do not have a you can get everything from timbre that is consistent over a spikey, biting pulse sounds to EKx 30 DUAL VCA mellower triangle wave effects. low noise, low distortion, wide bandwidth, low given frequency range; take the control voltage feedthrough. Both exponential guitar as an example. An open Considering the low cost and and linear control voltage Inputs simultaneously string has more harmonics, and is wide applicability of the SSWS, available..... $24.95 t$2.00| louder, than the same string fret­ it's worth building one. Despite EKx 40 FULL FEATURE VCO ted higher up on the fingerboard. its simplicity, the SSWS is a Full feature VCO with ramp, triangle and Interestingly, the SSWS mimics useful signal processing device voltage controlled pulse. Exponential control that produces its own family of of frequency over accurate and stable this type of effect exactly. You 100,000:1 range. Linear FM Input and hard and can set the A and D controls for a unique sounds. soft sync..... $29.95 l$2.00l fairly mellow high register sound, while the lower regions sound much Each kit features the Curtis Electromusic brassier. This is tremendously I.C.'s to implement a full function Voltage Controlled Card. All connections are useful for bass synthesizer E d ito r brought to the card edge in a configuration patches; you want the lower notes compatible with Molex or 22 pin .156 center to be a little brighter so that edge connectors. they cut, but you also want the R iA Electronics, Inc. 1020 W. Wilshire , Oklahoma City, OK 73116 (405)843 9626

POUPHONU January/February 1982 27 TWO-O-TWO

BY MARK STYLES

The next generation of digit­ memory" switches, and playing a sign. Normal stage lighting is al synthesizers (Synclavier, Fair- note on the keyboard (in the set usually not adequate to read such light) has been on the market for mode, each key represents a dif­ small print, but after a few days a while now. Casio's contribution ferent instrument sound). When of use you'll probably end up is the Model 202, a cousin to the play/set is switched to set, all memorizing the presets anyway. big boys at Bell Labs and New keyboard notes play middle A, England Digital that costs about making it easier to discern dif­ l/64th as much. While the 202 ferences in tonality. Once you certainly doesn't have all the return the play/set switch to bells and whistles of these former play, you are ready to make music. giants, it can certainly stand its The 4 position vibrato switch own in today's troubled economy. The 202 is a polyphonic 8 note instrument that features 49 instrument sounds, which range from electric piano and celeste to harp and electric bass. Thanks to

My first impressions of the 202 were that more tone memory switches and better vibrato con­ trol were needed. However, after using it for a while in a four piece rock band I find that I hardly ever use more than 2 or 3 lets you choose between no vibra­ different voices in one tune. to, slow/deep, fast/deep, or Setting up for the next tune is fast/slight vibrato. This slide very rapid and can be done between switch has detents for each stop, numbers. While independent con­ and the transition is made smooth­ trol of the vibrato speed and ly with no glitches in the sound. depth would certainly add more A sustain switch lengthens the versatility to the instrument, for the two LSI chips and 14 bit DACs, decay of all notes even if you ensemble playing the 4 position the 202 delivers some amazingly play in a staccato manner. The vibrato switch is adequate. realistic sounds. Some of its tuning control varies the pitch The operation manual for the features are a presettable tone approximately plus or minus 1/4 202 is printed in 4 languages, and memory circuit (which allows in­ tone. Another useful feature of is well diagrammed and to the stant access to any four preset the 202 is its built-in speaker, point. All features and proce­ sounds), three different vibratos, which makes it a snap to set up dures are explained in detail, pitch tuning, volume control, a and practice anywhere. along with examples. One section built-in speaker, and sustain The Model 202 is lightweight of the manual lists all the voices switch. (15 lbs) and stylish in design. along with their note range, which To keep both packaging and The specification sheet mentions is a useful guide for orchestra­ price economical, Casio designed that it is available in velvet tion. While each voice is play­ the presettable memory system. black and walnut grain although I able over a 4 octave range, some This allows you to set up and have only seen the all-black voices are placed one or two oc­ instantly recall 4 of the 49 units. The preset instrument taves below middle C. This re­ available instrument sounds. You names are screened in above the sults in the instrument being able preset an instrument sound by keyboard, but the printing is to cover a total of six octaves. switching the play/set switch to small and from more than a few For example, the Piano 2 preset set, depressing one of the 4 "tone feet away looks more like a de­ begins an octave higher and has a

28 POUPHOM January/February 1982 slightly different tonality from Piano 1. with a natural decay is chosen (piano, harp, etc.) Standard accessories that come with the 202 are and more than 8 notes are depressed and left down, a music rack, plastic dust cover, AC cord, and the additional notes will sound a3 soon as the decay polishing cloth. Optional accessories include a cycle of the first eight notes are completed. volume pedal, sustain pedal, hardcover case, and Still being curious about the 202's operation, stand. The volume pedal is a standard attenuator I tracked down the American division of Casio (15 which makes use of a stereo plug; if you are running Gardner Road, Fairfield, NJ 07006), and for $3 I through an amp, it's cheaper to patch a standard ordered the 26 page service manual. (incidentally, DeArmond pedal between the instrument output and while the service manual is clear and to the point, amp. The sustain pedal will hold the sound (up to 8 it could be longer; and occasional translation dis­ notes) depending on the instrument voices you are crepancies result in an awkward sentence or two.) playing (organ, string sounds). A plucked instru­ Technically speaking, eight key common signals ment sound will still fade away, although with sus­ are generated by one of the LSI chips and applied to tain its decay is greatly lengthened. Mechanically the keyboard. Any depressed key short circuits the speaking, the sustain pedal is very ingenious. It key common signal and a kev input line, which in is a simple arrangement of two metal pieces holding turn begins the sound generation process. The two a small switch. This is completely enclosed in a LSI chips work together to generate digital wave­ thick, 1/4" piece of flexible rubber-like material. forms. One controls the "consonants", and the sec­ The result is a simple, lightweight, dust-free foot­ ond LSI chip controls the "vowel" sounds for an switch. instrument voice. Each LSI chip has its own 14 bit Instrument voices. The instrument sounds are DAC. After the DAC the consonant signal is fed to a high quality, distortionless, and on the whole, very filter block, which consists of one high pass filter interesting. A little practice with the sustain and and two low pass filters. After filtering, the vibrato can yield some remarkable sounds. Some of consonant signal is fed to a volume control circuit the preset sounds are: that compensates for the various output level varia­ tions of different selected tones. 3 various piano sounds The vowel sound block utilizes three low pass 4 cla sounds filters. The filters are switched in and out of the 3 koto sounds ; iff* circuit, depending on which instrument voice has 7 guitar sounds been selected. If a new voice is selected while you 3 electric guitar sounds are playing, a cut circuit switches in to prevent 7 assorted organ sounds - pipe, electric, glitches or distortion. accordian, and bandonian Overall evaluation. The Model 202 is an update 4 various woodwind instruments of the Model 201 which came out last summer. The 3 strings - cello, viola, and strings 201 featured 29 voices (not so well chosen), no 4 brass tuning facility, and lower fidelity. The 201 did 2 bass - standard and electric synth type bass have a few nice extras that were dropped, such as an Synthe-Sound - a humorous distorted clavi- auxiliary input and effects send/return connections. net type sound Casio learned quickly from their mistakes, and came, Elect. Sound - a synthetic phased out with the Model 202 this spring. type sound On first approaching the 202, the sheer number of different instrument sounds can be bewildering; The pipe organ sounds are particularly rich and but, they are logically laid out in families of realistic. The bandonian approximates a tinny, high instruments and much better labelled than the Model pitched Vox or Farfisa organ sound. The harpsichord 201. Personally, I would have liked a few more sounds are also very realistic. electronic synth sounds and a few less guitar The Casiotone sometimes makes dramatic use of sounds. A number of the sounds such as celeste, sweeping filters, which is very apparent on the pipe organ 4, harp 1, electric sound and electric Shakuhachi (Japanese bamboo recorder) voice. The bass are exceptionally fine-sounding. Shakuhachi has a very noticeable "wah" effect which The 202 is an excellent instrument for the is just shy of being too cute. price ($500-$650 depending on where you purchase The insides. As you would expect from a Casio it). The 202's features make it great for prac­ product, the instrument is well constructed and ticing, songwriting, or playing on stage. My only neatly laid out. The power supply is very solid complaints involve the on/off switch and vibrato; looking, with 6 fast blow fuses. A 4", 10 Watt the on/off switch is located next to high "C" (once speaker is completely sealed in a wooden housing and while doing a frenzied solo I inadvertently shut off packed with sound absorbent material to give a loud, the instrument), while the vibrato lacks flexibili­ pleasing sound. The main circuit board utilizes two ty. If Casio added a variable speed/variable depth 64 pin LSI chips which work in tandem to produce the control for the vibrato, along with some kind of various sounds. The rest of the circuitry comprises pitch bending option and a slight revoicing of some two 14 bit DACs, various filters, and gain controls. of the instrument sounds, they would have a truly All connections to the main board are Molex type. outstanding live performance instrument. Components are well labelled, with some Japanese For even twice its price, nothing can come symbols interspersed. Several test points are lo­ close to the 202. It is clearly the result of many cated about the board as well. hours of research into technical, musical, and The keyboard is a separate module (about 1.5" financial considerations. Judging from the progress thick) that connects to the circuit board via a 16 Casio has made in the last year, they could conquer pin Molex connector. It is well built, with a the music market within two years. This producl light, quick action; all white keys have rounded shows creativity, efficiency, and craftsmanship ■ edges, making the keyboard great for slides. Only all at an affordable price. the first 8 notes depressed will sound. If a voice

PQUPHQNU Jam air i / Febri /or i ’ 1982 29 by Bill Rhodes

one rotary switch. The programmer has two banks of eight presets for a total of 16 total presets. You can lock the program by flipping a safety interlock on the rear panel of the instrument. Overall, the synthesizer sec­ tion gives you typical slow decay­ ing filter sweeps, brass, B-3 (organ), flute, bass, polysynth percussive sounds, heavy modula­ tion sounds, strings, and the like, which are all the more con­ Another polyphonic (eight triggering circuit (Korg calls it venient because you can tuck them voice) mini synthi-orchestra hits their "bowing effect") provides away safely in memory when you hit the market! But what is refresh­ overlapping attack envelopes. on the right sound. This section ing about Korg's latest release is This is particularly helpful in is slightly noisy, but with proper that up to three different voices obtaining good string sounds, noise gating and EQ it is great per note can be played simultane­ since "real" string players do not for the studio as well as live. ously. I'm not comparing this have identical attack characteris­ Preset sounds. There are two instrument to a Prophet 5, or OBX, tics due to such differences as piano modes and a clav setting, Opus, Jupiter, Orchestrator, etc. phrasing, acoustics, and style. I all of which can be damped by a - this baby is in a class by it­ like the string sound, principally footpedal for sustaining charac­ self. There are many different because it has a rich chorus, does teristics. The clav mode is espe­ functions available, and each one not sound too reedy, and is low- cially nice when used with the becomes more intriguing as you noise. It is reminiscent of the flanger to make those funky clavi- experiment with it. earlier Delta and Lambda synthe­ net sounds. The Trident, which lists for sizers, but seems richer in so­ Modulation options. There's $4195, incorporates six major fea­ nority. delayed vibrato, with adjustable tures in its 46 lb. frame. These Brass section. 16' and 8' rate and depth; the joystick, are: voices are available, with com­ which has an adjustable pitch • A separate string ensemble plete filter control and VCA ADSR. range, can bend pitch up or down, with bass and treble EQ; However, as in the case of many trill/vibrato, or open the filter. • A brass ensemble, with brass emulator keyboards, there is Summary. Since the string, complete ADSR and extensive fil­ an infernal trigger glitch that brass, and synth sections have tering capabilities; occurs with certain filter set­ separate outputs (which therefore • A programmable synth with tings. Also, the brass sound is can be individually processed), 16 presets; too weak, not like the character­ and since the overall sound quali­ • Three useful presets for istic meatiness of the Oberheim or ty is so good, the Trident is a piano/clav; Prophet brass sounds...but I said great instrument in the studio or • A damn good flanger that I wasn't going to compare apples on stage. Once you get familiar is relatively quiet and fattens up and bananas. Assigning the with it, it's easy to use; but many of the voices; and flanger to the brass section gives best of all there's the richness • A joystick that can pitch a fatter sound, but without it of sound, which would normally bend, vibrato/tril 1, or open the there is only one oscillator per take three keyboards to produce. filter. note. Incidentally, the brass Play some string lines, add some The five octave keyboard can section also includes single and brass, call up one of your be split, allowing any combination multiple triggering. favorite polysynth patches, punch of up to three voices to be as­ Programmable synth. The dual in the flanger (which can be as­ signed to either end of the key­ oscillators (which can be de-tuned signed to any or all sections); board, or the entire keyboard. for fullness) provide pulse, then realize that you are creating The graphics are well laid out, square, and sawtooth waveforms; all these sounds on one keyboard! the controls for each functional the pulse can be pulse-width modu­ You can play most of the popular section and intelligently laid lated with its own rate control synthesizer sounds we know today out, and the switching is (mostly) (both oscillators produce the same while layering strings and brass color-coded to allow for easy waveform at the same time). There on top in real time. It i_s differentiation between function, is a complete ADSR for the VCA, amazing - which makes me wonder output, modulation, and triggering but not the VCF. Korg seems to all the more why they had to name related switches. want to use a rotary switch in­ it after...chewing gum? String section. 16', 8', and stead of separate attack, decay, 4' string voicings are present, sustain, and release controls for (Editor's note: If you want with all voices being affected by their filter, so you can't opti­ to hear what the Trident sounds the bass and treble EQ controls. mize for punchiness. The filter like, it is used extensively in A de-modulation control erases the is a 24 dB/octave low pass type Bill's upcoming release on Jazzi- chorusing mode, and a unique re­ and can be coarsely adjusted with cal Records, "Key Essentials".) ty 30 POUPHONU January/February 1982 Like many Polyphony readers, I promote my band through live performance and cassettes. To simplify promotion, I've come up with a "universal" promotion card that is inexpensive and useful. I basically took a piece of post card sized stock (5.5" by 4"), and printed the band's logo, address, and phone number on the left hand side (see photo). By adhering to this size, the card provides the following functions: • Post card. Good for send­ ing to people on your mailing list when you want to promote a gig. • Cassette liner. The card can be folded twice and tucked inside a cassette. Having your own cassette label looks better than using the ones provided by manufacturers. • Table setting card. A lot of gigs occur in clubs or restau­ rants where people sit at tables. ask people to write their name and You can rubber stamp or overprint address on it and leave it with information on the right hand side the band for news of future gigs of the card (such as "Album avail­ or albums. able from cashier for $7.95" or • Bulletin board card. If going to lose it right away. whatever), fold the card in half, you have a nice looking logo, a So there it is, a multipur­ and leave it standing up on the card like this really shows up on pose promotional tool that's fast table. This is also a good way to bulletin boards. and easy...and you can do it your­ promote your next gig, or to get • Business card. And this self, tool)! names for your mailing list - just one's big enough that they're not

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POUPHOMW Jan nary / Febri lary> 1982 31 2419-030), Iskander (Polydor 2925- very from alcoholism. The other 5 re -v ie w 021), Sweet Okay (Polydor 2441- tunes are faultless uptempo in­ 048). Supersister was a Dutch strumentals, including Sample's hot back-up, Tina's tight bass­ band from 1969 until 1975, who mastery of keyboard synthesizers. lines and the occasional dub tech­ started as a very tight, conserva­ nique lift this from mediocrity. tory-trained rock band and gradu­ Colin Newman Provisionally En­ ally evolved into a still-tight titled The Singing Fish (4AD cad Jerry Harrison The Red and the jazz parody of themselves. Full 108). A variety of instrumental B l a c k (Sire 3631). Talking of quirky rhythms, fast changes, textures - from electronic day­ Heads' rhythm guitarist/keyboard- and hummable melodies, these are dreams to chomping rock - from ist sounds even more like recent records to play for friends who multi-instrumentalist Newman. Talking Heads, backed by the per­ believe that nothing good ever He's from the English band Wire, sonnel and facilities of "Remain came out of rock and roll. one of the more interesting des­ in Light" and Byrne/Eno's "Bush of cendants of new wave. Ghosts" (reviewed May/june 81). Tangerine Dream Exit (Elektra Harrison's singing is similar to 5E-557). Take $100,000 worth of Deutsch Amerikanische Freundschaft

Byrne's, and his music indicates gear, a drumkit and two months in Die Kleinen und Die Bosen (Mute the studio and what do you get? that he was important to the de­ Stumm 1). I think this is

velopment of "Bush of Ghosts". A Unfortunately, 40 edited minutes D.A.F.'s first record (March 1980) of $100,000 patches. It's not burnished and meaty production and they've released a couple quite rock, and it's not quite able to stand with the best of since. I've heard that the newer avant-garde - it's just two months them. one(s) aren't as experimental as of twisting dials with a beat. Of "Kleinen & Bosen" and that would course, the patches are VERY nice. David Byrne Songs from the Broad­ be a shame. It's full of wonder­ way Production of "The Catherine Everfriend Tropicsphere (Jazzi- fully strange synthesizer lines, Wheel" (Sire 3645). Byrne hasn't cal 009033), Sphere of Influence freaky lyrics sung crazily (in been idle either, as this album (Jazzical 105072). Playing clas­ German, of course) and assorted indicates. An assortment of nor­ rude interruptions by sax, guitar, mal, abnormal, and treated instru­ sical piano and keyboard synthesi­ zers, Bill Rhodes manages to out- synth, and voice. Definitely out ments play out fast, Byrne-ish flash his acknowledged influences of the ordinary. rock with his odd touches. As Chick Corea, Keith Emerson, and usual there are some fascinating Rick Wakeman. The musicianship is Stuart Dempster In The Great electronic alterations, and about flawless, although the synthesi­ Abbey of Clement VI (1750 Arch a third of the album features zers are used mostly for melodic 1775). Remember "Inside", where Byrne's affected lyrics (including fills and ornamentation. Paul Horn played solo flute inside a couple of "found vocals" as on the Taj Mahal? Well, Stuart "Bush of Ghosts"). I can't ima­ Dempster plays trombone (side 1) gine it on Broadway. Paul Winter Common Ground (A & M 4698), Callings (Living Music and plastic sewer pipe (side 2) inside this French cathedral, and Eurythmics Never Gonna Cry Again- Records 1). Jazz saxophonist Paul Winter creates musique concrete at times it's hard to believe /Le Sinistre (RCA 68, 12" sin­ when he plays to recordings of you're not hearing a synthesizer gle); In the Garden (RCA 5061). whales, dolphins, wolves, and into a tape loop. Ex-Tourists Dave Stewart and Ann eagles. Sometimes imitative, Lennox make up Eurythmics, and the sometimes making a tune out of a Jon Gibson T w o Solo Pieces album bears much resemblance to call, sometimes just playing out (Chatham Square 24). Jon Gibson Tourists material. The single, of the spirit of the animal, Win­ works with patterns, both as a however, extracts the best tune ter shows a real affinity and visual artist and on record. Side from the LP and an unreleased flip affection for his fellow crea­ 1 is a rigidly structured pipe side. "Never Gonna Cry Again" is tures . organ drone, the second side is a driving rocker with several nice random phrases on a flute drawn touches (like the electronic from a narrow range of choices. noises and French horn), and "Le The B-52s Party M i x (Warner Bros, mini 3596, E.P.). "Tacky" As you might suspect, Gibson is Sinistre" is a sinister tune based from the Riley/Reich/Glass school around footsteps and a grand piano describes the B-52's perfectly, with their beehive hairdos, lava of microscopic composing. bass line. lights, off-key vocals and cheesy The Tapes Party (Passport 9842). DEVO New Traditionalists (Warner melodies. Party Mix is supposed Bros. 3595). DEVO has been doing to be dub versions of some of A lot of "new wave" relies heavily on effect, but some composers what they do long enough that they their songs, but these seem pretty can probably do it in their sleep. straightforward with only an occa­ write material that would stand up What they do, for the uninitiated, sional echo-out. Fun if you're in under any production. The Tapes, are quite traditional song struc­ the mood. from Holland, write strong, intel­

tures bopped up by having all the ligent material which doesn't seem instrumental parts (except drums Serge Blenner's La Vogue Magazin to have attracted the attention it and a little guitar) played on Frivole (Sky 059). Synthesizer deserves. Check it out. catchy synthesizers. The lyrics and rhythm box, rhythm box and wouldn't bear quoting, but the toe synthesizer - I think this stuff Simple Minds Sons and Fascination (Virgin 2207). Synthesizer sample taps anyway. comes in tubes. and hold keeps time, while voice Supersister A Present from Nancy Crusaders Standing Tall (MCA and guitar weave simple tunes (Polydor 2441-016), To the Highest 5254). Joe Cocker's earthy sing­ around it. Simple Minds have a

Bidder (Polydor 2310-146), Pudding ing perfectly balances the slick good feel for not rushing things, and Gisteren (Polydor 2480-153), uptown jazz of the Crusaders, with or bogging them down with unneces­ Superstarshine Vol. 3 (Polydor bittersweet lyrics about his reco­ sary frills.$ 32 rouPHONy January/February 1982 eOUIPfTEm EXCHPOGE

PUT POLYPHONY TO WORK FOR YOU. List equipment for sale or trade, job openings, positions wanted etc. Equipment exchange classified rates for individuals offering goods or services for sale or trade: 25c per word, 20 word ($5.00) minimum charge; Commercial establishments: 50c per work. Prices, zip, phone numbers count as one word each. DISPLAY CLASSIFIED; $15.00/inch, one inch minimum, camera ready art to be supplied by advertiser. All classified advertising must be prepaid. Advertisers using a Post Office Box for responses must furnish Polyphony Publishing Co. with a complete street address and phone number. Readers should respond directly to advertiser. Polyphony is not responsible for claims made in ads, or the result of any transactions. Polyphony reserves the right to edit or refuse any ads submitted.

NEW MINI-MOOG - still in factory FOR SALE Gnome - Oz combination carton - $1000 plus shipping. $125. Excellent condition. Ken Job Openings ARIES owners: Assembled Aries Gott, PSC#1 Box 2614, Travis AFB, system 300 modules (never used). CA 94535. Phone: 1-707-437-2108. SYNTHESIZER MANUFACTURER seeks AR-318 S/H, noise, clock $75, all literature included. owners of VIC, PET, IBM, etc. AR-328 Reverb/output $130, AR-339 micros for analog synthesizer Multimode VCF $155. Assembled controller interface software value:$815 ($545 unassembled) - Test equipment development. Graphics experience will sell all 3 above modules for necessary. Payment in equipment $300. Also, AR-310 module case SYNTHESIZER CALIBRATORS, kits or and royalty. Respond with (unassembled) $60, AR-320 Keyboard assembled. 1/3 octave pink noise informal resume and example of case (unassembled) $40, AR-326 test tapes with warble tones. your code to Polyphony Box A20305, power $20. Call Harry Poole (803) TEAC 2A upgrade mods. Write to: Oklahoma City, OK 73156. 667-4883 for details, or write ARCAS Engineering RFD#3 Burthill 1300 Valparaiso N-10, Florence, SC Rd., Winchester, NH 03470 music equipment 29501. PAIA PROTEUS I Programmable Preset Recordings ROLAND VK-1 Organ with built in Lead synthesizer, Factory Assembled, Bought new in Sept. 81, BEACON STAR - synthesizer/space LIL DAVID leslie $900; Sequential music on cassette tape. $5.00 Circuits Pro-One with case used less than 5 hours (still in original carton), want to move up check/money order to Chuck Larrieu $485.00. Call after 6PM CST Box 294 corte Madera, CA 94925 504-737-9237 to a computer, $450.00. V. Walraven, 4812 Lionel Ave., "its good stuff", Texarkana, TX 75503 (214) 838-5642 2720R MODULAR SYNTHESIZER System, TECHNO DE-Facto the new 60 minute never used, $300; Gnome/Oz CASIO M-10; purchased November cassette by Walt Whitney, 14 combination, never used, $125; Avante/Rock songs guaranteed to Stringz 'n' Thingz w/stereo 1981, perfect condition, stock. entertain. Send $5.00 ppd. to: option, new, $500; Fender Copy Will trade for Programmable Drum Set or $100. Bill Drew (618) Sub Sound P.0. Box 2411 Overland, Bass Guitar w/case, 4125; BIC 80Z 692-0234. MO 63114 money-back guarantee Turntable w/cartridge, new, $150. Alan Skidmore, Rt. 7, Box 184 So. COMPLETE PAIA Digital 8782 Charleston, WV 25309. (304) Keyboard. Cassette interface, 4 S u p p lie s 768-8797, (304) 442-5397. cassettes, over two road cases of equipment including D/A, Quash, BLANK AUDIO TAPE: AMPEX AND SCOTCH PAIA Synthesizer Modules: two 4780 Curtis Dual VCA, Patch cords and (reel-reel). Also empty reels and sequencers, one 4771 regulated all documentation. Must sell, boxes. Send for information: power supply, one 4740 envelope $400.00. Dave Mettle 1075 RECORDING SUPPLIES generator, three 2720-2A VCOs, one Beechwood Rd. Columbus, OH 43227, 1058 Oakview Drive 4730 VCF, one 2720-1 VCA, one (614) 235-0716 Cleveland, OH 44143 2720-11 envelope follower, one 4711 mixer, one 2720-12 Two 4720, two 4770, 4730, 4710, inverter/buffer, all mounted in 4740, 4711, Seq 4780, 8780 & Lite ra tu re two 4761 wing cabinets, assembled keyboard & Encoder, 2720-1, '-2, and working with patch cords and -3L, -3B, -4, -5, -8, -7, ~2A, & manuals - $450 or offer. .Trade -11 including switching system COMINGI THE PREMIER ISSUE OF: for recording equipment or ??? $500 or best offer, must sell. James Einolf, P.0. Box 162. Bruce (412) 341-0396. Franktown, CO 80116. (303)

688-0294. PAIA 8750 PROTEUS I factory calibrated, New $400. ELKA mod.88 The low cost newsletter that allows hobbyists and experimenters to share ideas, circuits, component electronic piano, 4-preset voices, applications, and much more. COMMON-MODE CASIO MT-30 Keyboards, 3 octaves, locking road case one month old will cover all areas of electronics, and will interest 22 sounds 8 note polyphonic, $325. Arp EXPLORER I — repaired the beginner as well as the experienced. self-contained speaker and amp., 6 and adjusted at ARP in July '81. Content: Circuits, sources of information (books, lbs. $165.00. Runs off 5 D size PEAVY series 400 MARK III Bass Amp magizines, etc ), along with application notes, batteries or Casio Adapter, 3 weeks old, all equipment in hints, ideas, etc on digital and analog electronics in $10.00. Send money order, the areas of audio, electronic music, recording, excellent condition with receipts personal computers, etc. Remember: COMMON cashier's check, or cash O.D. for all repairs and adjustments. MODE is not a magizine, but a low cost newsletter. Sound Electraa, P. 0. Box 17206 Duane T. Gworek, 253 - 14 st. Minneapolis, MN 55417 (612) Niagra Falls, NY 14303. m o r e in f o ? PGS ELECTRONICS 727-1482. WRITE US. P.0. BOX 735 TERRE HAUTE, IN. 47808 PAIA Stringz 'n' Thingz kit, never MUST SELL: Assembled PAIA 4700/S removed from original carton, Most of the info found in COMMON-MODE will come from its with 8780 D/A and 2720-11 Envelope $225. R. Hopkins (713) 229-1265. readers. If you have something of interest to share, let us know1 Follower. make an offer. Will Even if its only one sentence!!!! Published writers will be consider trade for normalized BLACET SYN-BOW, Fully assembled, compensated for their work. We want your writings, comments, synthesizer. Jeff Jacobsen, Box calibrated by the factory, $90. suggestions, ideas, etc. The more input we have, the better we 64, Logan, Utah 84321 (801) Jim Ellsworth, (415) 391-9555 can serve you! So Don’t Delay, There’s Much To Come! 752-8819 evenings. days, (415) 648-0307 evenings. - Write Now For Free Information! -

POUPHONU January/February 1982 33 TAPE TIMERS— ) BE7EA1X& ...... continued from page23 RULER Specifications Input resistance Balanced: 20k Ohms each leg to ground CUT-OUTS Unbalanced: 20k Ohms "In from Circuit": 100k Ohms

Output resistance by Craig Anderton Main out: 56 Ohms "Out to Circuit": less than 1 Ohm

Have you ever been recording THD+N (+4 dBm, 1.23 Vrms, into 600 Ohms) and wondered how much time was 20 - 20 KHz: less than 0.009% left on the supply reel, or how much time had elapsed on the take- S/N ratio (A-weighted)

up reel? Well, it happened to me -98 dB re +4 dBm output level just one too many times, and what with necessity being the mother of Common mode rejection invention... 200 Hz: 100 dB Note that both rulers are 2 kHz: 80 dB designed for use with 3600 foot 20 KHz: 60 dB reels of tape (Maxell UD 35-180 et al); differently calibrated rulers Frequency response would be required for shorter tape 10 Hz - 100 kHz, +0/-0.25 dB lengths or different reel sizes.

For greatest longevity of the Maximum output level rulers, I'd suggest photocopying +15 Volt supplies: 9 Vrms into 10k Ohms, or cutting out this page, and 7.75 Vrms into 600 Ohms (+20 dBm) pasting the timer rulers on to + 9 Volt supplies: 5.4 Vrms into 10k Ohms, thick cardboard or posterboard. 4.65 Vrms into 600 Ohms (+15.6 dBm) Using either ruler is simple. Referring to figure 1, place the Slew rate ruler against the surface of the 10 Volts per microsecond appropriate reel so that the edge with the arrow points to the out­ side flange of the reel, and the Parts List inside edge (at the other end of Resistors (all resistances in Ohms, 1/4 W rating) the calibrated scale from the 30.1k, 1% metal film arrow) is pointing at the inside RI ,R2

edge of the reel. Read the amount R3 9.31k, 1% metal film 10k, 1% metal film of time directly on the scale in R4 lk trimpot (CTS X201R102B or equivalent) minutes; double times for 7.5 IPS R5 CD • 100k, 5% carbon composition or film — ^0 CD DO operation, or halve times for 30 R6/7/9 a> S_ Q_ R8 56 Ohm, 5% carbon composition or film i—i IPS operation. 100 Ohm, 5% carbon composition or film — 35 4— R10, RI1 c O A” There it is, a tape timer — 30 C

Note: The following is available from TOLECO Systems, Box 401, Kingston, WA 98346: #GG-1 kit of parts - includes NE5532, PC mount jacks, and etched/drilled/plated glass-epoxy printed circuit board (but less "other parts"), for $14.00 plus $1.00 postage and handling in the U.S. and Canada. Circuit board only (order #GG-2), $5.00 postpaid in U.S. and Canada. Washington state residents add 5.3% sales tax. No COD orders.

34 POUPHONU ------January/February 1982 THE VOICE 400 The Fastest, Most Versatile and Musical Synthesizer Voice Available Oscillator A Oscillator B continuous waveshaping, continuous waveshaping variable pulse width, mod­ from saw to sine, AR enve­ ulation by S/'H or LFO, low­ lope g en erato r or LFO er octave, linear F.M. modulation, hard sync to VCO A. Keypad and Bank Switch Filter Selects one of thirty-two High pass, Low pass, Band presets. pass all modes are 24db/ oct. Controls include Reso­ Operating Mode nance, Response (continu­ Switches ously variable) ± : ADSR control Live, Memory and modulation, S/H or LFO Edit functions. mod, Noise source, Key­ board tracking. Output Section mixes your external signal Voltage Controlled into the delay, mixes Dry/ A m p lifie r Delay, and output volume has its own ADSR and fea­ control. tures low noise and wide dynamic range. Analog Delay wide range low noise delay line operates from flanging to multiple wide range Low Frequency Oscillator with continuous waveshap­ repeats. Regeneration and LFO depth control will create a wide ing of three waveforms. LFO may be modulated by the Attack range of effects. Release envelope generator.

The Voice 400 answers the need for a programmable syn­ * A voice for a sequencer or computer. thesizer that’s versatile enough to be all these things: * A complete synthesizer for wind or string controllers. * A complete keyboard instrument with the optional SMS * A programmable filter and/or a programmable delay Model 430 Digital Keyboard. line. * An expander for your present synthesizer whether Quality components have been carefully selected for this instrument. Great effort has been taken to insure that the ef­ mono or poly. * An acoustic instrument-controlled synthesizer when fects of temperature and vibration are minimal. When used with a pitch-to-voltage converter. you’re ready to play, the Voice will be too. . . accurately, and every time. #430 Digital Keyboard Sequencer •16 sequences o f up to 64 notes each programmable from the keyboard—1000 notes total •3 axis joystick for pitch bend, filter and mod depth **New Note assignment for ultimate lead “feel” •Built in LFO with two waveshapes and rate LED •Digital circuitry for drift-free performance •Portamento •3 position octave switch (digitally implemented) •Full length 61 note keyboard •Instant transposition to any key for both keyboard and sequences •Sequences may recycle, play once and end or advance from one sequence to the next •Footswitch input to start and resync sequences •Remote selection o f Voice 400 presets »Fine cabinetry with genuine walnut finish

P.O. Box 40267 San Francisco Ca., 94140 Tel (415) 824-4837 East Coast Office: 8 Tyler, Norwell Ma., 02061 (617) 659-2618 \m w FH3©M] [Mm

Veloci-Touch' Controller

* INDEPENDENT CONTROL VOLTAGES FOR VELOCITY AND PRESSURE * VELOCITY SENSITIVE TRANSIENT GENERATOR

* USE WITH PRACTICALLY ANY KEYBOARD, ANY SYNTHESIZER * PAIA 4700 SERIES MODULE OR RETRO FIT PACKAGING AVAILABLE * LOW COST

The new Veloci-Touch controller from PAIA adds time and an output control that’s continuously what may be the two most important parameters variable from normal to inverted transients. Use any electronic keyboard can have - Velocity and as a filter parameter control for the most natural Pressure. timbral changes ever.

Velocity is a control voltage proportional to how Even that’s not all. The Veloci-Touch controller hard you play. Pianissimo and the voltage is low. also provides an output proportional to the Fortissimo and it’s high. Use this parameter with pressure you apply to the key after it’s down. a VCA and presto...output level changes that Imagine • tremolo the natural way. follow your playing. The best part of this minor miracle from PAIA is But, since “loud” and “soft” mean more in that it’s non-denominational. You can retro-fit it human terms than just level changes, the Veloci- to essentially any synthesizer from any manufac­ Touch controller also provides a velocity sen­ turer. At a price that’s so low you won’t believe sitive transient generator with variable decay it’s possible.

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RMA Electronics, Inc. Dept. VT, Box 14359, Oklahoma City, OK 73116