Digital Processor Reviews

Many years ago I bought the first model of the Audio/Pulse ambience synthesizer. Like many audiophiles, I was convinced (and still am) that the standard two-speaker stereo experience provides an unsatisfying concert-hall impression. But the Audio/Pulse didn't remain long in my stereo system. You see, at best the unit provided a fair reproduction of the sound of my upstairs bathroom, topped off with a nasty flutter echo. I already get that sound every morning in the shower.

When a manufacturer sets out to design and build a product, be it in high-end audio or any other field, the final retail price is usually a prime consideration. Parts and assembly are only part of the equation; there also must be enough buyers to amortize the design and development costs. If the product is to be a flagship model—something a company hopes will give a lift to its entire line—engineers will sometimes throw caution to the winds, designing a product without thought to its ultimate price, which is only set after the design is complete. When Madrigal Audio Laboratories set out to design their No.30 Reference Digital Processor, they appear to have chosen exactly this approach.

Computer audio is more than just a pleasant distraction. For the jaded reviewer, USB digital converters and the like are an escape from that humdrum, if only because they bring with them so many variables: myriad combinations of different platforms, storage devices, operating systems, device drivers, media players, codecs, word lengths, sampling rates, connection protocols, and more. Challenging though they may be, computer-audio products are a tonic for reviewers inclined toward apathy.

"We like to make things," Roy Gandy, Rega's founder and owner, once told me. "It's what we do." Or maybe it was Rega's chairman and chief engineering honcho, Terry Bateman. Rega products are designed and manufactured in the south of England. So far as I know, no one at the Rega facility, on the Temple Farm Industrial Estate, has committed suicide; the same cannot be said of workers at the factory in China where iPods are made. Al Gore is on the board of Apple. Al, what do you think?

Back in the late 1980s, it seemed a good idea: Separate a CD player's transport section from its D/A circuitry so that each could be optimally designed, and, as D/A technology improved, the sound of your CD player could be upgraded by replacing the outboard D/A processor. The catch was that the transport and D/A chassis needed to be connected with a serial data link: S/PDIF in optical or electrical flavors, or balanced AES/EBU. To minimize the number of cables required, the format of that link embedded the clock data within the audio data, which rendered the link sensitive to interface timing uncertainty, or jitter. (See "Bits Is Bits?," by Malcolm Hawksford and Chris Dunn.)

I've been reading a fascinating book, Leonard Shlain's The Alphabet Versus the Goddess: The Conflict Between Word and Image (New York: Viking, 1998). Shlain's thesis is that the invention of the alphabet was the cause of immense changes in primitive society, upsetting previously widespread norms of gender equality and horizontal (rather than hierarchical) social relations in general.

Sure, Stereophile gets letters to the editor. We also get some colorful responses for our "Manufacturers' Comments" section. (Vince Bruzzese and Roy Hall are literary standouts among their component-making peers.) And, as one of the magazine's Contributing Editors (Audio), I get lots of personal mail from readers seeking my advice. I thought I might share some of these letters with you, and my responses.