SONIC: RESTORATION' PART ,'2 JULY 1991 US $2.95 UK V .75 CAN $3.50 MONITOR AUDIO , STUDIO 10SPEAKER EXPENSIVE., BUT ;14141 ENE IliGH-END' SOUN'D AND/LOOKS: (11 I. Alf,/ " If 1.117 4 NEW ,LIF IN" CASSETTES o , 11/ 9,r d. él TESTED ra y ÑArri%(1 ;. BLAUPUNKT NEW YORK') /14;)#// / - CAR TUNER/CD PLAVá .. \.k.1'1;, /t.p. TUUi CRE=R1 SUrl CF43 #1X147-736,F095 5#710272 0674 FEB 93 t' MR F 8 MAMELL JR P4 . 7778 FRANCES DR PLEXPNDRIP, UP 22306 ea po aways :eeninte 1flh0t:.e restaniaraaa 0104119, .1911 ,010111.1 dcom stereo components have Why Use Two Mono Amplifiers? a loyal and devoted following, The ability to deliver very high power into complex having earned a reputation among loads is a prerequisite for superior sound reproduction. audiophiles, engineers and musicians Power supplies capable of delivering the energy necessary for extraordinary performance at for high power, high -current amplifiers are massive. But affordable prices. Now Adcom introduces there are practical limits to the size and weight of stereo its newest amplifier, the no compromise GFA-565, for amplifiers designed for home use, as well as heat dissipation those in pursuit of absolute power and sonic perfection, and reliability constraints. Consequently, the use of two but who prefer not paying a king's ransom. Adcom GFA-565 mono amplifiers offers optimum sound The Evolution of Adcom's GFA-565 definition, detail and dynamics, satisfying even the most demanding perfectionist. Adcom's new mono GFA-565 evolves from the design of the critically acclaimed GFA-555, greatly extending More Sound, Less Money its capabilities. Representing brute strength, it delivers Like the GFA-555, the new Adcom GFA-565 sounds 300 watts at 8 ohms, 450 watts at 4 ohms and an awesome superior to amplifiers costing two and three times as much. 850 watts at 2 ohms* Most significantly, it will accurately It is so powerful and pure that it may be the last amplifier drive even esoteric loudspeakers which present loads as you ever buy, even if you upgrade your loudspeakers low as I ohm. several times over the years. And that makes the GFA-565 Inspired by the GFA-555, the new GFA-565's an extraordinary well -regulated, high -current power supply has an bargain OO enormous reserve capacity to meet tremendous dynamic considering demands, resulting in distortion -free reproduction on a its exceptional II/ continuous basis. performance. details you can hear o u *Continuous power output, 20 Hz -20 kHz <o.02% THD, measured in accordance with FM specifications. lI Elkins Road, East Brunswick, NJ 08816 U.S.A. (201) 390-1130 Distributed in Canada by PRO ACOUSTICS INC. Pointe Claire. Quebec H9R 4X5 Enter No. 3 on Reader Service Card Adcom's GFP-565 Preamp: Pure and Simple. Wee Noble reCOrvey pnOrq Ia1M 9 / moat& ore -sea po.M phone. Um* in Cont., to 1,11., -ono Vaasa°, on - - tuner - 1111~11111, - tape t 0.3 a - tape t - rnleW.u. In Search of Sonic Perfection, Adcom Three Sets of Outputs for the Perfect Took the Path of Least Resistance Balance of Performance and Flexibility The fewer circuits a musical signal encounters on its You can use one or more sets of outputs: I) BYPASS - way to your loudspeaker system, the greater its muscial direct -coupled before tone controls, filters, etc. for the most purity will he. Now, through obsessive attention to detail direct path to your power amplifier while retaining control and design ingenuity, Adcom has created the GFP-565 - of volume and balance. 2) LAB - direct -coupled with no the world's first affordable preamplifier with direct, linear output -coupling capacitors yet with tone, filter and loudness gain path circuitry. By combining the GFP-565 with any controls. 3) NORMAL - same as LAB but with highest of Adcom's power amplifiers, you can experience the quality output capacitors for use with amplifiers needing exceptionally lifelike sound which has astonished even the extra protection of ultra -low -frequency roll -off. the most demanding critics. Bi-amped and tri-amped systems are easily accommodated by this flexible arrangement. From Input to Output, Pure Convenience The minimalist aesthetics of the GFP-565 are the Signal Path is deceptive in their simplicity. Without being overly complicated to use, this preamplifier is able to integrate as Direct, Pure and and control all of the components in the most sophisticated of music systems. There are five high-level inputs as well Simple as Possible as a phono input. A separate front -panel switch allows the use of an external processor. only when needed. leaving C- r. both tape circuits free. And, of course, you may listen to one input while recording from another. More Sound, Less Money have a reputation for !t"' Adcom stereo components i sounding superior to others costing two and three times --1111,n more. Keeping faith with this tradition, Adcom took the path of least resistance. Why not do the same? Ask your authorized Adcom dealer for a demonstration of this remarkable stereo preamplifier. Please write or call for a fully detailed brochure. You'll discover the best value in high performance By gold plating all input and output jacks, and then directly preamplifiers. mounting al/ jacks, switches, potentiometers and other laboratory Pure and grade components on a double copper -plated, glass epoxy printed ¢ fircuit board, signal losses and noise are dramatically reduced. simple. details you can hear ó II Elkins Road. East Brunswick, NJ 08816 U.S.A. (201) 390-1130 Distributed in Canada by PRO ACOUSTICS INC. Pointe Claire. Quebec 119R 4X5 Enter No. 23 on Reader Service Card ° TRApg JULY 1991 VOL. 75, NO. 7 llon3aH. neBa ii Trrian'dnielepojsfió Y azaCjevDtt Bum 2 F. 'o w6 Stax/Volt Singles, page 82 Restoration, page 26 FEATURES SONIC RESTORATION OF HISTORICAL RECORDINGS, PART 2 Michael R. Lane 26 NEW LIFE IN CASSETTES: DIGITAL DUPLICATIONS John Eargle 38 EQUIPMENT PROFILES MONITOR AUDIO STUDIO 10 SPEAKER D. B. Keele, Jr. 44 BLAUPUNKT NEW YORK CAR TUNER/CD PLAYER L. Feldman and I. Berger 56 CARY AUDIO CAD -50 AND CAD-50sL MONO AMPS Bascom H. King 68 MUSIC REVIEWS ta = CLASSICAL RECORDINGS 78 ROCK/POP RECORDINGS 82 JAZZ & BLUES 86 DEPARTMENTS SIGNALS & NOISE 4 Monitor Speakers, page 44 TAPE GUIDE Herman Burstein 8 AUDIOCLINIC Joseph Giovanelli 11 AUDIO ETC Edward Tatnall Canby 14 BEHIND THE SCENES Bert Whyte 18 .-11101"-% The Cover Equipment: Monitor Audio Studio 10 speaker The Cover Photographer: Michael Groen 71,L _ . ? Audio Publishing, Editorial, and Advertising Offices, 1633 Broadway, New York, N.Y. 10019. The .`0°. nuan Bureau Subscription Inquiries, (800) 274-8808; 46 in Canada or other foreign countries, (303) 447-9330. Cassettes, page 38 A NEW BALANCE CD -narhIN- } TUIIER evinson R , R TAP( I !` 7 UK2 TUE I IYPui 0011iTOR TAPS 2 N! 28 O UT PREAMPLIFIER I \R r O!! SELECTOR MONITOR SELECTOR RECORD SELECTOR OUTPUT LEVEL The Mark Levinson N°28 Preampli- fier is at once a continuation of the "narH, D, . Mark Levinson traditions of musi- evinson cality and enduring quality, and an entirely new implementation of tech- POWER SUPPLY nology that will set the pace for PLS-226 innovation in high-performance audio in the 1990's. Mark Levinson products have offered the advantages of balanced interconnection for many years. The N°28 introduces a new execution of balanced circuitry called a DIDO (Differential In/Differential Out) that provides fully balanced operation throughout (not converting to single - ended for internal processing) while still rejecting common -mode noise from source inputs or arising within the unit itself. All versions of the N°28 have 2 balanced (XLR) inputs as well as balanced output connec- tions. Even single -ended signals benefit from the DIDO, since it rejects common -mode ground noise as it converts single -ended signals to differential at the input. Your local Mark Levinson Dealer can provide complete details on these and many other refinements ii the design of the N°28. More important, you can hear for yourself how this preamplifier tips the balance in your favor. arir.vinson Mark Levinson® products are designed and manufactured by MADRIGAL AUDIO LABORATORIES PO. Box 781, Middletown, CT 06457 FAX (203) 346-1540 ` ' SIGNALS & NOISE V.PJEditor: Eugene Pitts III Art Director: Cathy Cacchione Associate Art Director: Linda Zerella Technical Editor: Ivan Berger Managing Editor: Kay Blumenthal Associate Managing Editor: Teresa A. Carriero Associate Managing Editor: Douglas Hyde Directory Editor: Ken Richardson Assistant Editor: Joe Wiesenfelder Reprise of the Bitstream tion filtering: (1) "To reduce the quanti- Assistant Editor/Music: Michael Bieber Dear Editor: zation noise in the analog audio band- Associate Editors: We at Analog Devices as leading width" and (2) "To improve the signal- Edward Tatnall Canby, Bert Whyte, B. V. Pisha suppliers of audio converter ICs-are to-noise ratio (S/N)." The phrase Senior Editors: Leonard Feldman, D. B. Keele, Jr., pleased to see in-depth articles on "quantization noise" is ambiguous, David Lander converter technology as and Shah fails to such "Music clarify. There are Contributing Editors/Artist: of the Bitstream" by Prasanna Shah three sources of quantization noise in M. Aldred, H. Burstein, D. L. Clark, (January). Because of the debate (and the conversion chain if a sigma -delta A. H. Cordesman, T. Costa, J. Diliberto, F. Driggs, J. Eargle, S. Elliott, J. Giovanelli, confusion) in the industry between D/A converter is used, two if a current - B. H. King, H. G. La Torre, E. M. Long, oversampled sigma -delta converters steering type is used. The first is the F.