Woo Audio has a stellar reputation and is held in high regard because of its tube-based headphone amplifiers, which rank with some of the best-sounding devices offered on the market today. When I heard that Woo Audio was coming out with a new solid-state USB DAC, it piqued my curiosity: could the company bring the sound of its wonderful tube-based gear to its solid-state digital piece?Additional Resources
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The WDS-1 DAC retails for $1,199. The review sample I received was the black version (silver is also an option), built completely out of anodized aluminum. The WDS-1 DAC does not possess external screws; it has an overall appearance that is sleek and modern. Its dimensions are nine inches wide by 12.5 inches deep by three inches high, with a weight of nine pounds. The front panel has a VFD monitor display that shows the sampling rate, along with which one of the two digital filters is engaged. It can also show the level of volume that the WDS-1 DAC is sending to the amplifier, allowing you to directly drive your amps without the need for a line stage. Below the visual display are four buttons that control volume levels, inputs, and digital filter selection. Found on the rear panel are a pair of RCA and XLR outputs, asynchronous USB 2.0, optical, AES/EBU, coaxial, and IEC inputs. Therefore, the WDS-1 can be driven by your computer or a transport. Woo Audio also sent me its new transport, the WTP-1, to use with the WDS-1 DAC for Red Book CDs. The WDS-1 DAC has a customized driver for Windows XP/Vista/7 and is a 24-bit/192kHz converter. The remote control that comes with the WDS-1 DAC is small and constructed out of aluminum. It can control any feature on the WDS-1 DAC or WTP-1 Transport.
In my experience with listening to solid-state DACs in the price range of $1,000 to $2,000, many of them do offer very good transparency, details, and dynamics with decent soundstaging. However, DACs in this price bracket often have two tendencies that get in the way of my listening enjoyment. First of all, many of these DACs produce an overall washed-out tonality that robs timbres of their natural warmth or richness. Secondly, there seems to be a lack of image density and air around individual players, resulting in a lean sound and lack of what I refer to as "meat on the bones." Because of these qualities, they make the overall presentation sound flat instead of three-dimensional.
Since Woo Audio comes from a tube-based background, could the company bring what tubes offer - rich timbres, grainless texture, air and image density - to the solid-state WDS-1? The answer to this question was clearly answered with my first musical selection: "Wheeling and Dealing" by the Milt Jackson Quintet featuring Ray Brown, from the album That's the Way It Is (Impulse!). The timbres/tonality of Jackson's vibes and Brown's bass fiddle were beautifully rendered in a rich, natural manner. The vibes sounded metallic and the bass sounded woody, just as they do in real life. The overall tonal perspective was slightly warm and full, without getting in the way of the details or pace of the music. As I was listening to the WDS-1 with this song, I kept thinking that this DAC was as "smooth as butter," which allowed me to really get into the music.
I listened to my next album, Blues for Bighead (Mapleshade) by bass player Andy McCloud, which was recorded with very high resolution/transparency. Therefore, it is a great album to test a DAC's ability to render micro details and the size and shape of the recording venue. The WDS-1 DAC did an excellent job of illustrating where the band members were sitting or standing in the recording studio. You could also clearly hear the very faint chatter between the players as they urged each other on during their solos. Also, the image density and air around them could be clearly heard, so the music did have some "meat on the bones" and never sounded lean or thin at all.
In order to evaluate the DAC's ability to deliver macro-dynamics, bass extension/control and pop to the music, I chose Herbie Hancock's classic fusion album Head Hunters (Columbia/Legacy) as my final selection. The WDS-1 is quite musical, almost analog in its overall presentation; however, on Hancock's song "Chameleon," which has a funk kick and a powerful bass riff, the WDS-1 DAC delivered the punch and drive of this music in a very realistic way. The bottom end was taut and powerful, without being loose or sloppy in any way.Read about the high points and low points of the Woo Audio WDS-1 on Page 2.