Parasound Zdac

Betwixt and Between

Equipment report
Digital-to-analog converters
Parasound Zdac
Parasound Zdac

Pocket USB streamers are all the rage today. Feather-light and foolproof, they fit in your trousers, fanny-pack, or handbag, and, voîlà, high-res music on-the-hoof. However, they do pose problems for dedicated home-based high-end platforms. Sure, tiny is terrific for portability or for strictly USB-based audio, but what about a larger system with outboard gizmos that asks for an optical input—Apple TV, for example—or components with a SPDIF output, like that aging CD player of yours? Zippo-sized streamers can’t accommodate that level of input switching, nor do they have the room for a robust power supply or IEC power cord socket. On the other hand, what if you still want a degree or two of portability and don’t want to blow the budget for a full rack-mount-size outboard DAC? What’s right for you?

The Parasound Zdac shrewdly splits the difference. It’s a member of Parasound’s small footprint series of electronics whose half-size width permits side-by-side mounting in a standard rack space. The $475 Zdac is based on a 24-bit/192kHz DAC chip, and can play music via USB from a PC or a Mac. However it also includes optical and coaxial digital inputs along with a front-panel headphone jack. As an aside, it’s gratifying to note that many are recognizing that computer media via USB isn’t the be-all and end all of digital audio—a notion that Parasound seems to understand, too. The Zdac accepts signals up to 192kHz on its coax and optical inputs and up to 96kHz on USB. In addition to gold-plated RCA unbalanced outputs, it serves up premium XLR balanced outputs (take that, little streamers!)—handy for longer runs to avoid noise. Its headphone output can drive headphones from 32 ohms to 600 ohms and has its own volume control. Power is delivered via a high-current op-amp operating in Class A.

Parasound worked closely with component-maker and DSP specialist Holm Acoustics in Denmark to develop the Zdac. It employs both a high-precision crystal clock and a re-clocking circuit on its three inputs. Premium parts include an Analog Devices AD1895 asynchronous sample-rate converter and an AD1853 DAC chip, the same item that Holm selected for Parasound’s Halo CD 1 CD player. The low-profile front panel houses a slender central display that tells you which input is active. To its right is the input selector knob and to its left is a power button, a volume control, and a 3.5mm jack for headphones.

Sonically the Zdac offers an immaculate soundstage, with velvety black backgrounds devoid of electronic hash or noise. Orchestral details, from the most delicate pluck of a harp string to the metallic peal of a distant triangle, seem to materialize in three-dimensional space rather than being artificially flattened against a shallow back wall. The array of percussion instruments featured in Copland’s Fanfare for the Common Man is reproduced in a spacious, reverberant acoustic, rather than in the dry, arid, lifeless soundfields of average entry-level USB/DACs.

During this evaluation I frequently listened to the Franco Serblin Accordo compact loudspeaker (review forthcoming), one of the final efforts of the late Mr. Serblin, the founder of Sonus faber, and a speaker of superb transparency and low-level resolution. Through the Accordo I played back selections from the Rutter Requiem and noted how the Zdac didn’t inject the common artifacts, such as the soundstage compression or the digital sheen and leading-edge prominence, that red-flagged budget DACs of a few short years ago. For me these first-and second-generation budget-priced offerings were uninvolving. They didn’t bring me closer to a performance; rather they created a distance, a remoteness. Not so the Zdac. The Parasound unit is all about space and ease in reproducing the timbre and texture of acoustic instruments and voice. As I listened to high-resolution downloads from HDtracks like Carole King’s Tapestry or James Taylors Fire and Rain, nostalgia kicked in as I was once more able to appreciate the analog engineering of that era—the acoustic bloom of the guitars and drums, the shocking lack of post-processing artifacts and the dry, heavy damping of today’s recording studio. No, the Zdac won’t take you quite as far harmonically as efforts from Berkeley or dCS or Esoteric—these big boys still have a refinement, focus, and fluidity that can be a little startling in the headiest systems. However, in the sort of real-world systems wherein the Zdac is likely to take up lodgings, my guess is that no one will be disappointed.


Inputs: Coax SPDIF, optical TosLink, USB
Outputs: Unbalanced RCA, balanced XLR
Dimensions: 9.5" x 8.5" x 10"
Weight: 5 lbs.
Price: $475

Parasound Products ,Inc
2250 McKinnon Avenue
San Francisco, CA 94124
(415) 397-7100