High-end audio companies take different approaches to staying successful. One way to maintain a market position is to continue improving fundamental designs, offering a little higher sonic performance with each model. The latest products from a company employing this approach will look and operate very much like their first products.
It seems to me that it should be possible to make a perfectly jitter-free CD transport without resorting to elaborate, expensive mechanical structures. This idealized transport would ignore all mechanical considerations of disc playbackvibration damping and isolation, for exampleand simply put a jitter-free electrical driver at the transport output. If such a circuit could be made, it wouldn't care about how bad the signal recovered from the disc was (provided the recovered data were error-free). The circuit would just output a perfect, jitter-free S/PDIF signal. The result would be the sound quality of the $8500 Mark Levinson No.31 Reference CD transport in $200 machines. Such a scheme would provide an electrical solution to what has been considered largely a mechanical problem.
But back in the real world there's no doubt that attention to mechanical aspects of transport design affects sound quality. Examples abound: listening to Nakamichi's 1000 CD transport with its Acoustic Isolation door open and closed; playing the Mark Levinson No.31 with the top open; and putting any transport on isolation platforms or feet are only a few of the dozens of experiences I have had that suggest that mechanical design is of utmost importance.
So many things in this world are designed for convenience, not for excellence. That's all right if you have a choice, but it becomes a problem when products designed for convenience become universal standards and are thus foisted on everyoneincluding enthusiasts, who must then live with a product aimed at the lowest common denominator.
The digital interface between CD transports and digital processors is a perfect example of this dilemma. The Sony/Philips Digital Interface Format (S/PDIF) standard was designed so that connecting two digital products required only one cable. This single cable carries left and right audio channels as well as the timing clock essential to making the system work.
I feel privileged to have followed the remarkable evolution of digital processors over the past four-and-a-half years. Since my first digital review—a survey of three modified CD players back in August 1989—I've been fascinated by the developments that have inexorably improved the quality of digitally reproduced music.
Not that long ago, digital audio was considered perfect if all the bits could be stored and retrieved without data errors. If the data coming off the disc were the same as what went on the disc, how could there be a sound-quality difference with the same digital/analog converter? This "bits is bits" mentality scoffs at sonic differences between CD transports, digital interfaces, and CD tweaks. Because none of these products or devices affects the pattern of ones and zeros recovered from the disc, any differences must be purely in the listener's imagination. After all, they argued, a copy of a computer program runs just as well as the original.
I've watched from the sidelines with great interest the recent debate in this column over Home Theater (footnote 1) At one extreme is the suggestion that Stereophile begin reviewing video and Home Theater products. The other end of the spectrum was best expressed by John Atkinson at Stereophile's 1993 High-End Hi-Fi Show in San Francisco. Hearing the booming bass overflow of a Home Theater demonstration blasting down a hallway, he said, "They've brought televisions to our hi-fi show!"
To many audiophiles, the name Boston Acoustics is synonymous with mass-market budget loudspeakers. Although many of its products have offered good value for the money, Boston Acoustics has never been known for driving the envelope of high-priced loudspeaker design (footnote 1). The company has been content to churn out well-designed, affordable boxes and let others attempt state-of-the-art loudspeakers. Until now.
I find it astonishing that two products built on completely opposing engineering principles can both have musical merit. Design goals exalted by one company are considered anathema by another, yet both components produce superb sonic results.
At a "Meet the Designers" panel discussion at the 1992 Los Angeles Stereophile High-End Hi-Fi Show, I asked a group of successful digital designers (footnote 1) each to state how much of a digital front end's sound quality they believed was due to the transport, digital processor, and interface between the two. There was virtual unanimity: Nearly everyone agreed that a digital processor accounts for about 50% of a digital source's sound quality, the transport 30%, and interface 20%.