Digital Processor Reviews

Mastering and recording engineer Barry Diament sent me 24-bit/96kHz WAV files of Equinox, the latest purist recording on his Soundkeeper Recordings label. This recording is available in multiple formats and resolutions (see www.soundkeeperrecordings.com) and features percussionist Markus Schwartz and three Haitian musicians on trumpet, electric guitar, and acoustic bass, among other instruments recorded live. I can't imagine the spacious three-dimensionality of this recording surviving a CD transfer intact. The hi-rez files of this tuneful, percussive music produced an enormous, airy space in which the instruments were clearly located and layered.

In the catchy "Yanvalloux," written in 1956 by Haitian guitarist Frantz Casseus, musical timbres were rich and warm where appropriate—for instance, on Jean Caze's flugelhorn, and on the finger-tapped, conga-like Haitian drums—while Monvelyno Alexis's hollow-bodied electric guitar had an appropriately fast attack and warm sustain. "Seremoni Tiga" features vocals and a tinkly, tambourine-like instrument, as well as trumpet and bowed bass. The Debussy's ability to produce both warmth and body and fast, icy cool, where each of those qualities was appropriate, reminded me of the best, most neutral phono cartridges. In short, whatever preconceptions digiphobes might have about digital sound would be quickly erased by listening to these superb-sounding hi-rez files.

Reference Recordings' HRx DVD-R disc of Eiji Oue conducting the Minnesota Orchestra in Rachmaninoff's Symphonic Dances, a 24-bit/176.4kHz recording downsampled to 24/96, produced a sensationally wide and especially deep soundstage in engineer Keith O. Johnson's traditional style: front-row width married to a back-row perspective of the reverberant field. Such a sound may not exist in nature, but it sure keeps me tuned in; instrumental timbres were, as usual, luxurious, yet images were exceedingly well defined by clean, well-articulated attack. While the strings were rich and satiny, the percussion was sharply, naturally drawn, and well defined deep into the recesses of the generous acoustic. It was even possible to ignore the fact that it "got stuck in the groove" at the end (11:55) of the first movement and had to be digitally "nudged" into the next "band." No format is perfect!

Reference's HRx disc of overtures by Malcolm Arnold, with the composer conducting the London Philharmonic, was equally spectacular, but I also have the AAA vinyl edition of this, and . . . well, you probably know where this is going. Particularly in the way the big drum thwacks pressurized my listening room and the airy expansiveness of the soundstage— trust me: You don't want to compare the DDD CD version with either the HRx or the vinyl edition (LP, Reference RR-48; CD, Reference RR-48 CD; HRx DVD-R, Reference RR-48 Hrx).

Herbie Hancock's River: The Joni Letters (CD, Verve B0010063-02), downloaded at 24/96 from HDtracks.com, was equally enticing, though far more intimately rendered. The Debussy could sound hard and cold when the recording was, or warm and somewhat soft when it was that—as the Hancock recording is.

Compared to what?
After a few weeks' worth of listening to dozens of files of various resolutions, I'd decided that the combination of the dCS Debussy's honest portrayal of instrumental timbres, fast, clean attacks, and its precision in carving out solid three-dimensional images with edge definition that was not artificially sharp or etched, was right up my sonic alley. I then switched to the Ayre Acoustics DX-5 universal player and was happy to hear corroboration of what I reported in that review.

There was no doubt that the Ayre was warmer and more saturated in the midrange, and it definitely had somewhat slower instrumental attacks overall. It sounded almost as if I'd inserted a tube amp into the system. Bells, cymbals, and other percussion instruments that should produce icy-cool, metallic textures were somewhat softened and muted. Double bass, too, sounded somewhat softer, warmer, and slower, with more emphasis on the wood textures and less on the string transient, all helping to create, overall, that relaxing "golden glow" I'd described in last month's review of the Ayre.

The Debussy sounded definitely leaner in the mids, had a faster attack from top to bottom, produced an airier, more expansive soundstage with greater three-dimensionality, and more solid, better-carved images. The Debussy bristled with energy and produced better image definition; the Ayre was more laid-back and mellow, producing less sharply drawn images. A system with a lean midband would probably benefit from the Ayre's sound, which might make a system already rich in that range sound too thick.

Tastes vary, but when I played the 24-bit remasterings of the Beatles albums via USB, copied to my computer from the USB dongle version of the set, the Ayre and the dCS produced completely different pictures—same words, but with different syllables accented (metaphorically speaking, of course). The Debussy produced faster attacks and showed greater finesse in delineating images, with more metal to the sound of percussion and greater emphasis on "snap and crackle," plus deeply felt, full-bodied, but taut bass. The Ayre's thicker, midband-rich sound, ripe in bass, produced versions of familiar songs that emphasized such elements of the mix as the Moog synthesizer parts, which are usually less prominent. The difference was what you might expect to hear from switching out cartridges, or by going from a solid-state to a tubed DAC.

The differences in sound between the Debussy into a preamplifier and the Debussy directly driving a power amplifier will depend on the preamp's transparency, dynamic capabilities, and overall quality. Sending signals directly to my Musical Fidelity Titan amp from the Debussy or through my reference preamp, a darTZeel NHB-18NS, I heard minimal differences. Given the darTZeel's price of $29,500, that's what you should expect.

I also compared the dCS Debussy to Playback Designs' MPS-5 SACD player and found them sonically more similar to each other with the Debussy driven via S/PDIF than either was to the Ayre DX-5. There certainly are big audible differences among various DACs, but which will best fit your system can't necessarily be determined by reading a review.

S/PDIF vs USB
Ayre Acoustics' designer, Charlie Hansen, has little good to say about S/PDIF. He claims that asynchronous USB performs far better, which is one reason he omitted an S/PDIF input from the DX-5. I could hear no differences between CDs played on the Audio Alchemy transport and fed to the Debussy via S/PDIF, and the same CDs ripped to and played by the Sooloos music server and connected to the Debussy via S/PDIF. I could also hear no differences between CDs played via S/PDIF, and the same CDs ripped and played via USB.

However, the 24-bit/96kHz files of Markus Schwartz's Equinox, transferred to the Sooloos and then fed via S/PDIF to the Debussy, sounded quite different from the same files decoded via the Debussy's USB port. The USB playback was noticeably airier and more spacious; the S/PDIF version sounded flatter and somewhat thicker, but also had more bass, which could have accounted for the thickness.

This was disturbing—I would have preferred to have heard no difference at all. It made me wonder: Since the Sooloos server is essentially a computer, why doesn't it have a USB output? That said, I heard no differences between the 24-bit Beatles files decoded via S/PDIF–Sooloos and MacBook Pro–USB, so perhaps something else was involved in the different sounds of the Equinox files.

Conclusion
You can't really fight it, nor should you: The Blu-ray disc excepted, the future of digital storage and playback is not any sort of silver optical disc. Rather, it will be hi-rez files downloaded from the Internet, stored on a hard drive, and decoded by an outboard, multi-input D/A converter such as the dCS Debussy. I don't see how even the most committed analog diehard would not enjoy the sound of high-resolution digital files decoded by the Debussy, fed via S/PDIF from either a dedicated music server like the Sooloos or via USB from a computer hard drive.

The dCS Debussy is a flexible, well-made, physically attractive multi-input DAC-preamp that makes use of dCS's highly regarded Ring DAC technology and discrete analog output circuitry. The Debussy's digital sound mirrors my general preferences for analog playback: fast, taut, extended, and dynamic, with no cover-ups: If the recording is bad, that's what I want to hear. If the recording is superb, I want to hear it in all its glory.

The dCS Debussy did both. My only complaint: you can't directly choose an input without scrolling. That makes for a very easy and enthusiastic recommendation.