Digital Processor Reviews

I felt like I'd just been offered a choice of 31 flavors of Baskin-Robbins ice cream topped with up to 57 varieties of Heinz ketchup, 57 condiments, and 47 brands of coddled cream. My head began to spin, my stomach churned, and my mouth grew very dry as I read that Gold Note's DS-10 ($2995) was a "chameleon DAC" with 192 setup options that enable it to "completely blend in with different music genres, giving the listener the opportunity to adapt the behavior of the unit to the music playing, to one's stereo system and, most of all, to the listener's taste."

In contrast to phono cartridges and analog tape recorders, digital audio converters distinguish themselves by the fact that they can be fashioned in an almost infinite number of ways. Therefore, the odds against two manufacturers' DACs or ADCs sounding exactly the same are extremely large.

Hi-fi system resolution has long been the cause of heated arguments. But when it comes to converting digital data to an analog signal, there can be no argument. Data go in at one end of a DAC and an analog signal comes out of the other end, with a noise floor directly rated to the combination of the converter's digital and analog resolution. Ever since I started measuring digital products for Stereophile, I have been expressing a D/A processor's effective resolution in terms of the equivalent number of bits.

At the 2019 AXPONA, I took part in one of my first official meetings, as editor of Stereophile, with members of the manufacturing community: the German company T+A. They were presenting in the room of Texas dealer Lone Star Audio, which was owned by the late Jim Hench. They had a corner hallway to themselves: two rooms and, at the time when I arrived, a hallway table brimming with coffee and pastries. Fortuitous timing.

This unique device is a solution to a problem that previously couldn't be solved.

There are, of course, any number of little boxes that can extract audio from the HDMI video bitstream; they began to appear on the market to fill a need for a way to route audio from a player's HDMI output In the recent past, you could buy a good-quality—even audiophile-grade—universal player and listen to SACDs via its good-sounding analog outputs. But good-sounding universal players are becoming scarce.

In an era when polar opposites compete as absolutes, it can be a challenge to acknowledge the different and equally valid ways in which audiophiles approach musical truth. But the reality is that our perceptions of how reproduced music should sound are determined, to a large extent, by how we approach the live experience.

Even as digital/analog processors were becoming a hot product category in the early 1990s, audiophiles were also learning that timing uncertainties in the AES/EBU and S/PDIF serial datastreams—jitter—would compromise any improvement in sound quality offered by these DACs. Some companies therefore introduced products to reduce or eliminate jitter—in the November 1994 issue of Stereophile, Robert Harley reviewed three such products: the Audio Alchemy DTI Pro, the Digital Domain VSP, and the Sonic Frontiers UltrajitterBug. I still have Stereophile's review samples of the UltraJitterBug and VSP, along with two contemporary DACs: a PS Audio UltraLink and a Parts Connection Assemblage DAC-1.

As our reviews of these products were published before Paul Miller's and the late Julian Dunn's development of the "J-Test" diagnostic signal, I performed J-Test jitter measurements to bring that 1994 review into the 21st Century. You can see what I found here.