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Engineering the Future of Loudspeaker Design Graphical Solution of Electrical Filters Increasing Sensitivity of Fm Tuners Multip

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Engineering the Future of Loudspeaker Design Graphical Solution of Electrical Filters Increasing Sensitivity of Fm Tuners Multip DECEMBER, 1956 50¢ ENGINEERING MUSIC SOUND REPRODUCTION The problem of building stable transistor amplifiers hinges on the stabilization of the individual stages. See page 47 for the details. Build this concrete.block speaker enclosure which is put to- gether like building blocks and which may be taken apart and reassembled easily in another location. See page 21. THE FUTURE OF LOUDSPEAKER DESIGN GRAPHICAL SOLUTION OF ELECTRICAL FILTERS INCREASING SENSITIVITY OF FM TUNERS MULTIPLE TAPE COPYING www.americanradiohistory.com SKITCH ...on his Presto Turntable "MY CUSTOM HI -FI OUTFIT is as important to me as my Visit the Hi -Ft Sowed .Salon nearest you to verify Mr. Mercedes -Benz sports car," says Skitch Henderson, Henderson's comments. Whether you currently own a con- pianist, TV musical director and audiophile. "That's ventional "one- piece" phonograph -or custom components- we be with the difference you'll hear why I chose a PRESTO turntable to spin my records. In think you'll gratified you records through custom hi -fi components my many years working with radio and recording when play your teamed with a PRESTO turntable. Write for free brochure, studios I've never seen engineers play back records on "Skitch, on Pitch," to Dept. AX, Presto Recording Corpora- anything but a turntable -and it's usually a PRESTO tion, P.O. Box 500, Paramus, N. J. turntable. MODEL T -2 12" "Promenade" turntable "My own experience backs up the conclusion of the en- (33'h and 45) four pole motor, $49.50 MODEL T-18 12" "'Pirouette" turntable gineers: for absolutely constant turntable speed with no 031/4,45 and 78) four pole motor, annoying 'Wow' and 'Flutter,' especially at critical with Hysteresis motor (Model T-18H), ,131.00 33'%s and 45 rpm speeds, for complete elimination of MODEL T -68 16" "Pirouette" turntable motor noise and 'rumble,' I've found nothing equals a (33%, 45 and 78) four pole motor, i. with Hysteresis motor (Model T -68H), PRESTO turntable. It's heavy ... it's brilliantly machined $170.00 .... it's the only instrument on which the genuine audio- phile should ever allow his records to be played." WALNUT "PANDORA" Turntable Cab- inet by Robert W. Fuldner, $42.60 Hear the difference when you play your records on "PIES/715P TURNTi4BLES 11NnNOlICS COIVONAEION AFFILIATE www.americanradiohistory.com THE BRITISH INDUSTRIES again .. that 414Firresistible impulse! 1 1 There are, apparently, some impulses which are positively irresistible. 1 I One of these is for uninformed writers to always try to be funny or sarcastic when they write about high fidelity. The case in point this mnth is the New Yorker's "Talk of the Town" and its ( ?) his ( ?) coverage of the recent New York High I Fidelity Show. 1 The "Talk of the Town" finds it pos- t Bible to be pleasantly sympathetic to a 1 group of citizens who inexplicably take a pleasure from wandering about New York City gaping at the cornices on old buildings. It can be warmly tolerant of match book collectors who, when they w meet, apparently wear shirts imprinted m like match book covers! These people o are OK in the New Yorker's book, but when a high fidelity show is visited, an attempt just has to be made to make all the visitors appear to be just plain "nuts." . Passing comments overheard in the cor- n ridors are quoted out of context, the Of noise is exaggerated and the fact that o completely different types of music are being played in different exhibit rooms has to be made to sound balmy. u The "Talk of the Town" comments that many exhibitors had their "little white 1 rooms" strung with velvet rope, "like a funeral parlor." Of course, funeral par- lors aren't amusing per se, but the associa- tion strikes "Talk of the Town" as something comic to point out to its read- ers. Now, we don't know how many sorts of velvet ropes there are, but we are sure that the ones used at the High Fidelity Show were not only similar to those used in funeral parlors, but equally similar to those used at the Pump Room, the 21 Club and in the lobby of the theatre where "My Fair Lady" is now being shown. Why reach from left field to make it sound droll, and make a pass at the people who stand behind it or in front of it? We wish that we could truly understand the compulsion which makes it necessary to treat the desire for quality in musical reproduction as if it were a sort of harm- less lunacy. Frankly, we just don't fathom it. We took a careful look at this column, and were made to wonder whether this writer, with his "unedu- cated tympanum," seriously meant to comment on high fidelity components or (over) www.americanradiohistory.com (continued) on the high fidelity show. Fully half of the space was given to a discussion of one manufacturer's television exhibit and another's short wave packaged unit, neither of which, of course, are high fidelity equipment anyhow. More than two- thirds of the article covered intro- ductions, the lyrics of a few records being played and the above irrelevancies. We, of course, have no way of knowing what sort of equipment is used by the Editor of "Talk of the Town" when he listens to recorded music, if indeed he does at all; but even if it is not worthy of the title "high fidelity equipment," it is probably infinitely better than the sort of thing he was listening to some years ago, and this upgrading of the entire field is demonstrably due to the efforts of the same high fidelity enthusiasts he pans in his column. As is well known, there are an awful lot of sincere and honorable men in our industry who have honestly striven to produce better and better equipment, trying to bring a greater degree of listen- ing pleasure to devotees of recorded music. To go out of one's way to make these people appear comic is certainly out of line ... especially at this time, when so many of the audience of the New Yorker have become seriously in- terested in the subject of high fidelity. We are, of course, not suggesting that high fidelity enthusiasts ought to cancel their subscriptions to the New Yorker. We certainly do not intend to cancel ours. And despite the rather shoddy treatment we think our industry has been accorded, we still find "Talk of the Town" well worth anybody's reading any week .. in fact, we heartily recommend it. On the other hand, those of us who take our industry (one could say our "art") seri- ously, would not be wrong to take the old pen in hand and drop a note when it appears that any publication is strain- ing violently in order to introduce a comic or sarcastic aspect to what is a worthwhile and progressive industry. We wouldn't attempt to match wits with "Talk of the Town." As Joe E. Lewis says, we might be entering the fray half pre- pared! But we will match sincerity of purpose any old day ... and we'll bet that our airedale can lick his airedale! Leonard Car' Leonard Carduner is President of British Industries Corporation, Port Washington, New York. BIC is an American company which offers you the finest of audio equipment . fully guaranteed, with service and spare parts available throughout the country. The B.I.C. Group consists of the following products: Garrard Record Players Leak Amplifiers Wharfedale Loudspeakers R -J Enclosures River Edge Cabinets Gentiles Tubes Ersin Multicore Solders www.americanradiohistory.com DECEMBER, 1956 VOL. 40. No. 12 a complete music center Sneeessor to RADIO. Est. 1917. amplifiers, tuners, speakers, cabinets: 5hgnizezad HIGH FIDELITY AU D i 0 THE ULTIMATE* EYCINEERINC MUSIC SOUND REPRODUCTION C. G. McProud, Editor and Publisher Henry A. Schober, Busirr.. Manager llarrie K. Richardson, Associate Editor Joan Dioguardi, Assistant Editor .lanet M. Durgin, Production Manager Edgar E. Newnan, Circulation Director Sanford L. Cahn, Advertising Director MEMBER Special Representalive- tE0 II. Thorpe Covington, !6 East Pearson Street, Chicago II, Ill. DEL 7 -0506 Mid Wes/ Rrpre.ventative- uE Sanford It. Cowan, 67 West 14th New York 36, N. F. Il'r.st Coast Representalires- James C. Galloway and J. 11'. Harbison, 633.1 Wilshire Boulerartl, Los Angeles 48. Calif. the all new SI000II 'ON 'l'I:N'l'S 20 watt amplifier *The Ultimate-in simplicity of installa- 'bout IIu-ie- liarold La te l'eure . ,enter tion and operation -in subtlety of dial and Edit .1'S Ittlurt 14 push- button control -in sourd engineer- Future of Loudspeaker Design-Norman .I. ('rowhnrst .. 19 ing accuracy -in flexibility; in crisp detail Ilraphical Solution of Electrical Filters -L. C. Ham ras 22 of music reproduction. l)onerete Loudspeaker Eueloanr -Phil .1. 11-a1)tsek _.._. 25 Design for a College Music Hoop -Merle Pleating and Elliott D. Fall 28 FEATURES: Six cabinet color choices including Increasing Sensitivity and Lowering Distortion in FM Tuners gold -tooled leatherette -24 carat gold finished bez- -Joseph Marshall 30 els. Controls are simple, easy -to- handle, yet com- Multiple Tape Copying E. Baird 36 plete- include 6 -db presence -rise switch, equalizer -H. control for 4 record compensation choices or micro- Semi -Solid Collier Encloser -H. P. F'oer..ter 39 phone and tape -playback equalization, inverse - feedback type bass and treble controls, Sherwood A. Folded Itorn Design- Hiehard :f. Greiner 40 exclusive "center -set" loudness control, loudness Coming Events 4.2 compensation switch, 12 db /octave scratch and Stabilizing Transistor Amplifiers -Richard H.
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