You are reading the older HTML site

Positive Feedback ISSUE 61
may/june 2012


Musings on Building a Digital Music Server: The Woo WDS-1 and a Little Patience
by Andy Schaub


"Oh, time is on my side, yes it is
Time is on my side, yes it is"
—The Stones

A few months ago, I started to consider the purchase of an Ayre QB-9 to use in my office system with my Blossom Blo-0299 fully balanced headphone amp because then, I would have what I had already; a fully balanced office headphone system, only it would sound better and I could get to 24/192 with my MacBook Pro. Sadly, I just couldn't justify the $2750 it would cost and I became mildly depressed. Not that there was anything wrong with the HRT Music Streamer Pro and Cardas adapter cables I was using, but it all lacked, "Je ne sais quoi". Then I heard that Jack Woo had come out with the WDS-1, a reference quality 24/192 DAC with USB and S/PDIF inputs as well as optical (TOSLINK) and AES/EBU; and the whole thing only cost $1199. Was it too good to be true? I had to find out for myself. So I wrote to Jack and asked if I could review one for Positive Feedback Online. He said, in characteristically polite fashion, that he'd be happy to supply a review unit as soon as he could catch up on production and to my great delight yesterday, some 3-4 months later, a black and silver WDS-1 arrived at my doorstep.

By now I had gotten so excited about the WDS-1 that I knew I had to hear it in the reference system, not just the office system; so I immediately unplugged my Sonicweld Diverter HR, Core S/PDIF cable and Berkeley Audio Design Alpha DAC (original version, I have doubts about the upgrade) and plugged the WDS-1 in in place of everything. I queued up my Mac mini (recently configured by hand by the folks at Pure Music for optimal sound) and played—for no particular reason—Steely Dan's Gaucho at 24/96 from In a word, I was stunned. I thought it would sound good, but I had no idea how good it would sound and it kind of blew my mind. I asked my girlfriend Lori to take a listen, and she was not so impressed; she felt it sounded a little muted and, over time, I came to understand what she was saying. The voices were a little recessed and it didn't have the deep bass and extended treble that I had come to expect from, say, my analog front end; but it was still musically very engaging and I listened to all of Gaucho followed by all of Natalie Merchant's Tigerlily, again at 24/96 from

woo audio

Despite Lori's initial reaction, I was very happy; but I do take her opinion seriously, so I decided to reinsert the Sonicweld Diverter HR into the system with the Core S/PDIF cable using a small BNC-to-RCA adapter I bought at Amazon. I queued up Gaucho again and now I have to admit I could hear greater dynamics and more "thwack" in the bass as well as a crisper, more extended treble. It wasn't perfect; it lacked a kind of holistic quality the Woo had on its own; but I believe it addressed Lori's complaints. So using the Sonicweld Diverter HR/Woo WDS-1 combination, I played Rebecca Pidgeon's The Raven at 176.4 and Diana Krall's The Girl in the Other Room at 24/96, both from and must admit I was delighted; but sticking in a $2888.00 USB-to-S/PDIF converter is hardly playing fair. So I decided to take another route. Let me mention, in passing, though that I still felt musically more engaged than I had with my Berkeley Audio Design Alpha, which sounded a little "dry" by comparison.

I took out the Locus Design Cynosure v2 and replaced with the Moon Audio Silver Dragon USB cable. Replaying, The Girl in the Other Room, I got a nice soundstage and more extended treble; but as had been my experience in the past, it came off as a little bright. So I went to the old bargain mainstay, the Moon Audio Blue Dragon USB cable. That was a much better match, with a very laidback but open treble and words dripping off of Diana Krall's lips. I knew I needed to live with this configuration for a while. It didn't sound as good as the Sonicweld Diverter HR, but it did address—I think—that "muted" quality Lori had described because the Cynosure v2 was designed with dCS equipment as a reference and I believe that my old dCS Debussy was very bright. So perhaps with the more neutral WDS-1 needed a more neutral—at least slightly more neutral—USB cable to bring out the best.

woo audio

I queued up Duo Sonatas - Mozart, Haydn by Podger & Rogers that I had downloaded from Channel Classics at 24/96 and got some very lovely sound with a nice sense of air and ambience and just a touch of richness to the sound as if adding a hint of maple syrup to what be an overly sharp plain yogurt. The more I listened, the more I liked it. So I also queued up Capriccio di Bravura, again at 24/96 from Channel Classics, by Rick Stotijn et al; they're was a loveliness to the midrange that seemed to perfectly compliment my Triode Audio Corporation TRV-A300SER 300B-based amp and Audio Note AN-E loudspeakers. I decided to crank the volume a little, because I tend to listen to vinyl and CD's fairly loudly, and I could suddenly hear a richness and depth to the double bass that I wouldn't really have expected from a DAC costing $1199 with USB conversion built in to 24/192. The violin and cello had a purity to them that revealed the WDS-1 really liked strings, but not at the expense of getting the hammer strike just right on pianos (although I think that the piano strike might have been the purest with the Sonicweld Diverter HR and Core S/PDIF cable installed).

The mezzo-soprano on Capriccio di Bravura also sang with a lovely tone. I was using a Locus Design Keynote power cable for all of this and a pair of Kondo Sound Labs KSL-LP interconnects with Eichmann Silver Bullet Plugs. I wanted to hear how the WDS-1 sounded at maximum resolution, so I queued up a 24/192 download of Lonely Woman by the Modern Jazz Quartet, again from I should mention that a fumble in the operation of iTunes might have cut off the last track of Capriccio di Bravura. I'm not really sure. Now Lonely Woman was an interesting case; it also sounded great on my reference system and surely the vibes rang like bells, but they did seem slightly distorted, slightly overloaded and perhaps not as sweet as my Sonicweld Diverter HR → Core S/PDIF cable → Berkeley Audio Design Alpha DAC. Still, perhaps the vibes are a little too closely mic'd, because it sounds like that kind of distortion, not a digital over or an analog overload; and the bass was, once again, impeccable and the treble crisp. The "thwack" on the drums was perfect, and imaging and soundstage spot on. Reconnecting the Cynosure v2 USB cable → Sonicweld Diverter HR → Core S/PDIF cable → Berkeley Audio Design Alpha DAC restored Lonely Woman to its former glory, and I was glad. But there was still a "flatness" or lack of life to the sound; still, it sounded more like analog. So what can I say? I guess, sometimes, you get what you pay for; but that should in no way infer that he WDS-1 that is not a very fine DAC. For the money, I have yet to hear anything else that comes close to my reference digital music server. As I recall—and it's been a long time—even my old Ayre QB-9 didn't come this close.

So what else am I to do with the Woo? Well, I really want to try it in the originally intended configuration. I connected my 17" MacBook Pro with 8GB of RAM and a 256GB SSD to the WDS-1 through a Locus Design Polestar USB cable, then to my Blossom Blo-0299 fully-balanced headphone amplifier—which I had had at my office—via a pair of AudioQuest King Cobra balanced interconnects and then through a short pair of balanced Kimber Hero interconnects switching back and forth between a copy of Like Minds by Gary Burton et al and the 24/96 download of Shangri-La by Mark Knopfler, both from In both cases, I also used the Denon AH-D5000's I had as my office headphones, finding it necessary to set the Blossom on maximum gain. I did find the sound to be a little bit bright; however, I was running the system cold, so I decided to let it all warm up and ran it for a while, continuously playing the 24/88.2 download of Like Minds that I had down sampled to 24/44.1 in Pure Music. I can say that after only 15-20 minutes, using the Kimber Heroes, the sound opened up tremendously. I also found that Heroes came closer to the Cardas interconnects I had used at the office in terms of tonal balance.

As I had at the office, I used a generic, heavy-gauge, shielded power cable with the Welborne Labs power supply for the Blossom; however, I used a spare Locus Design Keynote with the WDS-1. I would put the headphones on every so often for a quick listen and continually found myself impressed with the increasing warmth and richness of the WDS-1 through the Blossom Blo-0299, the treble spreading out to reveal layers of detail previously unheard in my office system. Again, to keep the experiment as pure as possible, I did not use the PS Audio Power Plant 10, but used a Power Wedge 112 instead as I had at the office. I noticed as time passed that the total balance really leveled out, and that it became increasingly enjoyable to listen to my "little", fully balanced office system. After about 90 minutes, the sound was really quite perfect and I decided that this evening I would be listening to late night music on my "office" system pretending that short window of time that I had not a care in the world. Several hours later, the sound had improved even more with a richness and dynamic range that made every note on the vibraphone ring as if live. The treble had backed off dramatically until it had reached the optimal balance. The sound of the WDS-1 does not offer the gossamer-like quality of the Ayre QB-9 nor does it offer the warmth and euphony of the Audiophilleo 1 / Rega DAC combination; rather, it has a sound all its own that I find most enjoyable, a rhythm and drive like a muscle car with finesse. I know I'll have sweet dreams tonight with Gary Burton and Chick Corea in my head.

After speaking with Cardas, they recommended that I try the 2 x 24 M pro audio cable if I wanted something that sounded like the adapter cable used between the HRT Music Streamer Pro and the Blossom Blo-0299, which they said was likely the G Master Reference. As a miracle of chance, I happened to have a twelve foot pair of the 2 x 24 M to use in live recording; so I connected those, all coiled up, between the WDS-1 and the Blossom and right from the start I got the richness and lush sound I wanted without the brightness I had heard the night before. It only took a few bars of the 24/96 download of The Girl in the Other Room by Diana Krall from to know I had something special on my hands. I was even able to reduce the gain of the Blossom, which took a little "grain" away from the sound; and that, my friends, is another example of synergy at work.

Kindest regards,


Woo Audio