Digital Processor Reviews

Don't have $80,000 to drop on dCS's four-component Scarlatti SACD stack that I reviewed in August 2009, or $17,999 for their Puccini SACD/CD player that John Atkinson raved about in December 2009? Even if you do, the new Debussy D/A processor ($10,999) might be a better fit for your 21st-century audio system. Sure, you don't get an SACD transport—or any kind of disc play, for that matter—but the odds today are that you already have a player you like that's got an S/PDIF output that can feed the Debussy.

John Atkinson asked me to review the dCS Network Bridge ($4250), which was designed to be paired not just with the dCS Vivaldi DAC ($35,999) running the current v.2.02 software, but with any DAC. This meant I was forced to endure several months with the state-of-the-art Vivaldi as a replacement for my reference dCS Rossini ($23,999). Oh, how I suffered.

The dCS Purcell is named after Henry Purcell, the English composer, organist, bass, countertenor who was born in 1659 and died in, alas, 1695. It's a digital/digital converter intended for consumer use, as opposed to the less elegantly packaged pro-audio version, the dCS 972, that I reviewed in February 1999. Both devices increase the sample rate and/or word length of the output from linear PCM digital audio sources like CD or DVD up to a maximum sample rate of 192kHz and a word length of 24 bits. According to the extensive documentation, this is achieved by "using extremely powerful and accurate digital interpolation filters, which yield an output signal having negligible levels of distortion."

It has been 20 years since I first became aware of the British company Data Conversion Systems, which manufactures audio products under the dCS brand. Rather than use off-the-shelf conversion chips, the groundbreaking dCS Elgar D/A converter, which I reviewed in our July 1997 issue, featured a then-unique D/A design that they called a Ring DAC. This featured a five-bit, unitary-weighted, discrete DAC running at 64 times the incoming data's sample rate—2.822MHz for 44.1kHz-based data, 3.07MHz for 48kHz-sampled data and its multiples—with upsampling and digital filtering and processing implemented in Field Programmable Gate Arrays (FPGAs). Oversampling to a very high sample rate allows the word length to be reduced without losing resolution, and use of a low-bit multi-bit DAC makes for very high accuracy in the analog voltage levels that describe the signal. (If this seems like voodoo, for a given signal bandwidth, bit depth and sample rate are related. To oversimplify, double the rate, and you can reduce the bit depth by one bit while preserving the overall resolution.)

Is anyone in this economy shopping for a four-box, rack-swallowing, two-channel SACD/CD player contending for the state of the art and costing $79,996? dCS is betting that its Scarlatti will attract a small crowd of those wealthy music enthusiasts who, in any economy, reliably pony up for the best. For the rest of us, the Scarlatti will be a spectator sport.

Well into dCS managing director Mike Story's attempted explanation of upsampling, there came an epic moment when the ever-expanding universe of his thoughts—which we had been following to new heights of digital enlightenment—broke free of our collective grip, snapped back on itself, and caused a conceptual implosion of nearly cataclysmic proportions. The blank, spent expressions on the faces of the journalists gathered in the small attic-like meeting room at dCS's Great Chesterford (UK) facility all seemed to say, "What the hell was that? Was it just me, or did you feel that too?"