dCS Debussy D/A processor
On the other hand, if you're already moving toward server-based digital playback, you just need to add something like an inexpensive Mac mini computer, a 1-terabyte hard drive, a small LCD screen, and some iTunes bypass softwarePure Music or the more expensive Amarraand with the 24/96-capable Debussy's USB input, you're in business.
The remote-controlled dCS Debussy is slim, sleekly shaped, and surprisingly compact for a component weighing 20 lbs. It has a full range of digital inputs: two S/PDIF (one RCA, one BNC), two AES/EBU that can be used individually or as a dual AES pair, and a true asynchronous USB port. The Debussy's USB, single AES, and S/PDIF inputs accept up to 24-bit PCM at 32, 44.1, 48, 88.2, or 96kHz sample rates. Its dual-AES input can handle 176.4 and 192kHz rates. There's also a BNC word-clock input, should you wish to add an outboard clock generator. The fully balanced design offers both XLR balanced and RCA single-ended outputs, adjustable level with a digital-domain volume-control. In a system with only digital sources, you can use the Debussy as a preamplifier.
Inside is the latest version of dCS's software-updatable "Ring DAC." This is a five-bit design, operating at 2.822 or 3.07MHz and handling the audio data in a proprietary five-bit format at DSD's sample frequency. All incoming digital data are oversampled to this format before being converted to analog.
According to John Quick of Tempo Sales & Marketing, dCS's US distributor, the Debussy's DAC and discrete balanced analog output sections are similar in basic architecture to what's inside the Scarlatti and other, less expensive dCS models. The singled-ended outputs follow the discrete stage with an op-amp buffer, however.
Setup and Use
Unlike the Scarlatti, the single-box Debussy is easy to set up, and even easier to use. Included is a luxurious remote control; its operation is intuitive, its feel slightly rubbery. It's not backlit, and it controls some features not found on the Debussy, so it has some extra buttons. The only aspect of the system remote that's less than ideal is having to scroll through the inputs; there's no direct selection of source from the either the remote control or the front-panel pushbuttons.
Pressing the On button on the front panel once puts the Debussy in sleep mode, which mutes the analog outputs and leaves the DAC close to operating temperature. Press On for longer than three seconds and then release it to turn the dCS off. Via the remote, you can put the Debussy to sleep, wake it up, or turn it fully off, but you can't turn it on from full off. You'll probably just turn it on once and leave it on thereafter.
The digital volume control has a range of 60 to 0dB, in increments of 0.5dB. Although the manual assures the owner that the Debussy's Ring DAC "has linearity to spare," dCS recommends setting the control between 20 and 0dB. A rear-panel level switch sets the full-scale outputs to either 2V or 6V RMS so that any setting between 20 and 0dB produces a reasonable volume level in the owner's system, whether or not he uses a preamp. The sample-rate indicator, a stack of seven LEDs, doubles as an approximate volume-control indicator, in 10dB steps.
The front panel also has buttons for Phase (absolute polarity) and Filter. The latter toggles between two filters of similar amplitude response but different time-domain behavior. Which you prefer is a matter of taste. While you can select a filter via the remote, the arguably more important choice of polarity is selectable only from the front panel. Those who obsess over polarity (I know many who do) will get a lot of exercise.
I was able to connect the Debussy, via S/PDIF, to both my Sooloos music server and a vintage Audio Alchemy DDSPro transport (based on Pioneer's upside-down disc drive); via a single AES jack, to my Alesis Masterlink hard-disk A/D converter and 24-bit/96kHz recorder; and, via USB, to a MacBook Pro laptop. I also had on hand a Playback Designs MPS-5 SACD/CD player and Ayre Acoustics' DX-5 universal player, which I reviewed in February 2010 and December 2010, respectively. And you thought I was only "that analog guy."
The dCS produced bass that was powerful, deep, taut, and well textured. Its overall attack was equally fast and certain, as in the bass, but it didn't sound hard or etched. Instead, image contours were ideally carved in space, producing, with hi-rez files, dramatically solid, three-dimensional images that appeared out of the pitch black one normally associates only with good analog playback.
The Debussy's top-to-bottom transient performance was equally satisfying: fast, yet delicate enough to avoid hard edges and harshness. Macrodynamics were seemingly unlimited; more noticeable were microdynamics, and the Debussy's ability to reveal small dynamic shifts that further extended instrumental decay than what I'd become accustomed to from familiar recordingseven CDs. Not surprisingly, then, the Debussy's rhythmic drive and ability to induce musical involvement were sensational, particularly with hi-rez recordings. While it may not have the Scarlatti's graceful sophistication and delicacy, the Debussy more than made up for it in exuberance and musical vibrancy.
Files ripped from CDs to either of my storage systems, or direct from a transport, or even upsampled to 96kHz via Pure Music, still sounded like CDs, with a relatively constricted, cardboardy quality that, in my opinion, is to hi-rez files what MP3 is to CD. The best CDs, from either the transport or the Sooloos, did sound very good, howeveras long as I didn't compare them to hi-rez PCM or SACD versions of the same material.