ELECTRONICS-MUSIC-HOME RECORDING February 1984 COMMODORE 64 MUSIC SOFTWARE REVIEWS BUILD: A JUST INTONATION GENERATOR A NOISE REDUCTION UNIT VOCAL BASICS 3-D VIDEO ISSN: 0163-4534 T H G O B G R H G I M S Y S T G M “ Let me overturn a “ The system inspires “ In truth,these "There’s no other way “ The interface with myth here—this is creativity and three little boxes to record a symphony the DSX exponentially the greatest drum box experimentation on (DMX, DSX & OB-8) by yourself....” enlarges the for sound and every level.” will do far more than possibilities of Sting (The Police) programmability....” we yet know howto what I can do.” David Sancious Musician/June 1983 make use of musically. Stewart Copeland May 27,1983 Jeff Lorber (The Police) Jim Aikin Obernotes/Fall 1982 Melody Maker Keyboard/ April 1983 June 18,1983 OBGRHGM eieCTRONICS.INC. Some things are better than others 2 2 5 0 So Barrington Avt. Los Angeles. CA 9 0 0 6 4 DX Digital DMX Digital DSX Digital OB-8 Polyphonic 700 Professional Drum Machine Drum Machine Polyphonic Programmable Stereo $1395.00 $2895.00 Sequencer Synthesizer Power Amplifier Suggested retail Suggested retail $1995.00 $4395.00 $895.00 Suggested retail Suggested retail Suggested retail ------ STAFF -------- PUBLISHER ISSN: 0163-4534 John S. Simonton, Jr. I \ % p h o r ^ EDITOR Craig Anderton VOLUME 9, NUMBER 2 EDITORIAL ASSISTANT Vanessa Else FEBRUARY, 1984 MANAGING EDITOR Linda Kay Brumfield TECHNICAL ILLLUSTRATOR Caroline Wood 3-D Viedo CIRCULATION By: Dr. Maury Deutsch.............................................. 8 Ramona French Peggy Walker Build A Just Intonnation Generator By: Vanessa E l s e ........................................................... 19 BOOKEEPING Cathi Boggs Music Software Review Commodore -64/CBM-64 PRINT PRODUCTION By: Craig O'Donnell ................................................... 14 Phuong Nguyen SEMCO Color Press NE572 Noise Reduction Unit By: Ron Oberholtzer ..................................................... 10 POLYPHONY (ISSN 0163-4534) is published bimonthly at 1020 W. Wilshire Blvd., PAIA PatchMod Oklahoma City, OK 73116, by Polyphony Publishing Co. Entire contents copyright By: Scott Lee .............................................................. 28 (c) 1982 by Polyphony Publishing Co. All rights reserved. No portion of this Product Review: Korg EPS-1 publication may be reproduced in any manner without written permission from By: Bill Rhodes ..........................................•................ 13 the publisher. Second Class postage is paid at Oklahoma City, OK 73125. Vocal Basics ADVERTISING rate card and deadline By: Danna Sorensen ...................................................... 17 schedule is available upon request. Contact Linda Brumfield at (405) 842-5480. DEALERS & DISTRIBUTORS bulk prices are available upon request. Contact Linda Brumfield at (405) 842-5480. 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(405) 842-5480 F o fy p h o i^ February, 1984 3 W IND PLAYERS VOCALISTS You can use your own instrument or voice to control any standard synthesizer, with more expressiveness than a keyboard. PENULTIMATE TO ULTIMATE COMPRES­ With these modifications, the SOR: CORRECTIONS AND MODIFICATIONS output noise is e s s e n t ia lly a trace of the input noise generated I included a couple of errors by Al. A TL071 gives good per­ formance, and even better results \ W A f l M in in the schematic for the Penulti­ mate Compressor; sorry i f I caused can be obtained with an OP-15. Please remember too that any wire THE GENTLE ELECTRIC any anguish. Here are the correc­ traveling for more than 1 - 2" PITCH AN D ENVELOPE tions : FOLLOWER 1. Change the value of R18, inches between the 572 and 5534s and any other audio signal must be R19 to 10k. shielded. Good single point Write for our free detailed 2. Add a 10k resistor be­ tween pin 7 of the NE572 and Cll, grounding is also very important. , brochure patch diagrams, C12. You can also add output capa­ and application notes. 3. Take four 10 Meg resis­ citors to the crossover outputs, tors, and connect one each to pins and bring the crossover outputs as Also available os modules for A rie s and 2, 4, 14, and 12 of the NE572. well as the high and low frequency S erge synthesizers, or as circuit boards • Connect the other ends of the compressed outputs to the front for custqrh systems. Dealers inquiries resistors to the positive supply. panel. You can then use the unit w elcom e. This adds a small bias current as a crossover or to process high which causes the compressor to and low frequencies separately, gentle electric turn on only after an input and mix them together further down W Dept P threshold is reached. The com­ the line. Another possibility is P.O. Box 132, Delta, CO 81416 to replace the 10 Meg bias resis­ (303) 874-7171 pressor then acts like a unity gain amplifier when there is no tors with pots for a variable input signal and dramatically re­ threshold control. With these EXPERIMENT WITH duces noise. changes, I think that a ll in all 4. Another m odification is this device is quiet, accurate, EKx Series to change C20, 21 from 10 uF to and clean-sounding and is truly 4.7 uF. I made an erroneous the Ultimate Compressor. statement that these caps control EXPONENTIAL Thomas Figueiredo the sustain, thus implying that MODULE CARDS larger caps give more sustain. San Francisco, CA This is not the case. These capa­ EKx 10 ADSR citors control the release time of envelope generator with exponential control TR-606 SYNC? of Attack, Decay and Release times over a the gain reduction action of the guaranteed .002 to 20 second range. No control compressor on signal peaks. A 4.7 voltaqe feed-throuqh.. $24.95 plus $2 postage It seems to me that since the uF capacitor gives faster response Roland TR-606 Programmable Drum EKx 20 VCF and a more "natural" sound. (Ed. with exponential control of pole frequency note: Many of you have asked Machine can sync up to other Ro­ over a 10 octave range. Jumper programmable land units, you should be able to for 24 dB/Oct. LP, HP, BP or A ll Pass response. about the polarity of these parts. Voltage controlled resonance. Low noise, 86 dB The + end of C20, C21, C22, and derive a sync output from the TR- below max. output. $26.95 l$2.00! C23 connect to the 572, while the 606's DIN connector. I f you re­ EKx 30 DUAL VCA - end connects to the outboard op corded this on tape, then you low noise, low distortion, wide bandwidth, low amp outputs.) could sync the TR-606 to the click control voltage feedthrough. Both exponential 5. There is a typo in Fig. track and thus synchronize over­ and linear control voltage Inputs simultaneously dubs. This would help make the available........$24.95 1$2.00| 3; C33 should be 5 uF, not 2.2 pF as shown. Also, C33 is not listed unit much more flexible, for exam­ EKx 40 FULL FEATURE VCO on the parts list. ple, this would overcome the prob­ Full feature VCO with ramp, triangle and lem of having the trigger out tied ; voltage controlled pulse. Exponential control 6. I f you want an output of frequency over accurate and stable level control, replace R34 with a up with the tom-toms. Does anyone 100,000:1 range. Linear FM Input and hard and 10k pot, and connect the wiper of out there know how to do this? soft sync........$29.95 I$2.OOI the pot to the output jack. John Herzfeld Each kit features the Curtis Electromusic 7. You can also change the Belmont, MA I. C . 's to implement a fu ll function 5534's compensation caps from 22 Voltage Controlled Card. All connections are pF to 10 pF; this gives better brought to the card edge in a configuration John — The main problem with compatible with Molex or 22 pin .156 center high frequency response and higher simply recording the click track edge connectors. slew rate. I f you have problems with oscillation or squeals, go on tape is that you need to condi­ RBiA Electronics, Inc. back to 22 pF. tion the analog signal coming from 1020 W. W ilshire , Oklahoma City, OK 73116 - (405)843-9626 4 February, 1984 the tape into a nice, clean, digi­ tal pulse capable of driving the Robert Carlberg’s TR-606. However, you might try recording the signal appearing at pin 3 of the DIN connector.