Over the years as a reviewer, I have tracked the swings of opinion and popularity of various audio ideas and technologies. Amid a sea of advanced designs that achieve powerful technical performance and laudable specifications, I'm reminded of a major blind listening test of 18 power amplifiers that I set up for the long-since-defunct UK magazine Hi-Fi for Pleasure back in 1975. We had "advanced technology" then: the transistor amplifier had matured and was well accepted by audiophiles. Prices of the review samples ranged from $300 to $3000 (equivalent to $1000-$10,000 in today's dollars). The auditioning sessions were graced by the presence of many industry leaders, among them the late Spencer Hughes of Spendor, Julian Vereker of Naim, Philip Swift then of Audiolab, Alan Harris then of retailer Audio T., Bob Stuart of Meridian, and John Wright of IMF (now TDL in the UK).
While high-priced equipment can easily acquire stature on grounds of outright performance and physical appearance, we critics have more admiration for genuine achievement at lower price levels. One such product was the all-triode SP8 preamplifier from Audio Research, launched back in 1982 and priced at $1400. This classically tasteful preamplifier came equipped with a medium-sensitivity phono equalizer and the usual tape and line inputs.
If you read much promotional literature for recently introduced high-quality equipment, you'll notice a common theme emerging: balanced connection. Balanced inputs and outputs are becoming a must for any audio equipment that has any claim to quality. The word itself has promotional value, suggesting moral superiority over the long-established "unbalanced" connection (for the purpose of this discussion, I will call this "normal"). What's my problem with this? Simply this: The High End could be paying dangerous, costly lip service to the received wisdom that balanced operation is the goal for an audio system.
Bass constitutes one of the least understood aspects of sound reproduction. Opinions vary greatly on matters of bass quality, quantity, and perceived frequency range or response. Moreover, the bass region is subject to the most unwanted variation in practical situations due to the great influence listening-room acoustics have on loudspeaker performance. Every room has its different bass characteristic, and changes in the position of speakers or listener also constitute major variables at low frequencies.
Although I retain a firm hold on the established audio world, and recognize and value all that it has achieved, I feel inexorably driven to make some space in my life for single-ended amplifiers—more especially, those that eschew negative feedback (footnote 1). A classic if costly example of the art is the Cary CAD-805C, which, to my ears, has earned the right to teach audiophiles what negative feedback really sounds like, and what damage it can do to the musical message when poorly handled. This shouldn't be taken as an out-of-hand dismissal of those many great pieces of electronics and amplification that use negative feedback—it is simply an acknowledgment, or even an assertion that negative feedback generates a sound of its own.
The Complete Guide to High-End Audio by Robert Harley 450+xxiv pp., $29.95 softcover, $39.95 signed hardcover. Published by Acapella Publishing, P.O. Box 80805, Albuquerque, NM 87198-0805. Credit-card orders: (800) 848-5099.
Many tube aficionados hold that amplifiers built with the venerable 300B tube hold the aces when it comes to sonic purity and beauty of harmonic line. Cary Audio Design's Dennis Had succeeded in producing what many believe is the definitive moderately sized single-ended triode (SET) amplifier: the CAD 300SE. This monoblock, powered by classic 300B Western Electric or derivative tubes, could provide 8–10Wpc, requiring the adoption of relatively moderate volume settings and/or sensitive, easy-to-drive loudspeakers. Cary also produced a lower-priced "integrated" stereo chassis, the CAD 300SEI.
In conversation with Cary founder Dennis Had at a recent audio convention breakfast, I learned that he had a long career in electronics, specializing in military/industrial high-power radio-frequency amplification and transmitters. However, his dream was always the re-creation of single-ended tube amplifiers, especially zero-feedback designs.
In the audio field, the British have traditionally thought "small," scoring hits both with their compact loudspeakers and with medium-priced amplifiers. The continued growth of the audiophile speaker market in the US, however, which favors larger loudspeakers, has at the same time stimulated the research and design of more powerful, excellent quality amplifiers. In their turn, these have placed increased demands on the speakers they drive.