Another demonstration of how much information the DirectStream DAC could retrieve came when I queued up the cut “Folia Rodrigo Martinez” from Jordi Savall’s CD La Folia 1490-1701 [Alia Vox] ripped to an AIFF file. The percussion instruments are quite vivid when played loudly, but often tend to fade into a background noise when played quietly. Or at least that’s what I used to think; the DirectStream DAC raised them above the noise level and made them audible at all times. The clack of the wood blocks was clearly audible throughout the entire piece, as was the clatter of the castanets. The DirectStream DAC also generated a wider, more stable soundstage than I usually hear from this piece. The dynamic level is constantly changing, and the DirectStream DAC made it clear how band leader/viola da gamba player Savall was driving those changes. There was unusually precise placement of instruments in the soundstage, as well. The Direct Stream DAC gave my subwoofer a good workout as it delivered a deep extension of the bass drum, with lots of power and impact I could feel as well as hear.
The Tallis Scholars’ recording Allegri’s Miserere & Palestrina’s Missa Papae Marcelli [Gimell] was recorded in a spacious church. On the cut “Miserere,” a main choral group is up front in the soundstage, while a small solo group is further back in the room. A good system makes it obvious that the two groups are spatially separate, and decent DACs will give the impression of how far they are apart. The DirectStream DAC revealed not only that, but also gave a spatial picture of the recording venue. Likewise, while singers in the main choral group weren’t exactly pinpointed, due to reverberation, their relative location was well-defined, as were their vocal characteristics. The vocalists weren’t portrayed as a homogeneous blob, as they sometimes are with other DACs.
I think there’s an unwritten rule that reviewers have to mention at least one female vocal performance in every review. So up next was Rebecca Pigeon’s audiophile fave “Spanish Harlem,” from her album The Raven. I had two recorded versions of the cut, an 88.2/24 FLAC and a 176.4/24 FLAC which had been remastered by Bob Katz. The DirectStream DAC made the differences between the two recordings easy to distinguish—the 176.4kHz recording sounded less mechanical and edgy, making Pigeon’s voice quite human-sounding. I felt like I could hear how she vocalized each word.
Okay, we’ve established that the DirectStream DAC plays CDs and PCM material quite well, but does it do as well on DSD recordings? To find out, I switched to a DSD recording: Alex de Grassi’s album Special Event 19 [Blue Coast Records]. Playing the cut “St. James Infirmary,” the DirectStream DAC captured more detail about guitar than I thought was possible. Starting with initial transients, the DAC reproduced the pluck of the strings sharply but with the resolution that told me when each string had been plucked. In the sustain part of the note, each note displayed its full harmonic characteristics, and then decayed off into silence, quivering in space for several seconds. The DAC caught de Grassi’s phrasing perfectly, giving the piece a bluesy tinge. While each note was individually captured in textbook fashion, they all blended together to form an organic musical whole, a song with a touch of swing. I don’t think I’ve ever heard a better rendition of someone playing a guitar. I’ve never heard a DSD DAC play the cut with such abundant musical detail, either.
To see if the DirectStream DAC would fall apart playing a recording of a full orchestra, I queued up Michael Tilson Thomas conducting the San Francisco Symphony in Mahler’s Third Symphony [SFS Media/Downloads NOW!]. The SFS Media DSD recordings of the Mahler symphonies may well be the most realistic orchestral recordings I’ve ever heard. The result: rich, accurate harmonics, well-defined spatial environment, dynamic changes ranging from barely perceptible to hammering blows that threatened my speakers’ well-being—and the breathtaking performance didn’t hurt, either. Instruments sounded spookily realistic and were scaled to create a believable impression of a large symphony orchestra. The DirectStream DAC played the recording effortlessly; the passive output stage never sounded strained or congested. After we’d listened to the Mahler Third, another audiophile buddy commented: “It really doesn’t sound digital anymore.” He’s never said that about any other DAC
The above impressions were derived using a preamp between the DirectStream DAC and my power amp and subwoofer, for reasons I’ve explained. But I wanted to test PS Audio’s claim that the DirectStream DAC will drive amplifiers directly, so I disconnected my subwoofer and used the DirectStream DAC to drive the power amplifier only. As I expected, the direct-drive mode yielded a slightly cleaner, more delicate sound, with even more spaciousness. Of course, absent a subwoofer, bass didn’t extend as deeply. But if you only have one power amplifier to drive, I’d go with the direct-drive connection.
My Audio Research DAC8 is a PCM-only DAC, so I could only compare it to the DirectStream DAC using PCM files. It’s still in Audio Research’s product line, selling for $4995, not far from the price of the DirectStream DAC. I acquired the DAC8 back in 2010, but although I’ve reviewed several excellent-sounding DACs, I haven’t yet been motivated to replace it. Or have I?
On “Folia Rodrigo Martinez,” instrumental detail was less distinct, and the percussion instruments tended to blend together in the background a bit. However, the dynamic contrasts and shifts which are so important to this performance were as forceful as with the DirectStream DAC. Instruments were well fleshed out harmonically, although they sounded just a tiny bit raw compared to the DirectStream DAC. As is usual, bass was very extended and powerful, one of the characteristics the DAC8 is known for. The DirectStream DAC’s bass power and extension seemed every bit as powerful as the Audio Research DAC8. No other DAC has ever achieved that.
The “Miserere” cut sounded very spacious, but the details of the soundstage, the reverberant space, seemed a bit less distinct than through the DirectStream DAC. The tenor soloist in the main choral group sounded a bit grainier than through the DirectStream DAC. The DAC8’s rendition was still well-defined and enjoyable, but the DirectStream DAC’s version was better focused and smoother by a tiny margin.
Rebecca Pigeon sounded very good through both DACs. In “Spanish Harlem,” the differences between the 88.2kHz and 176.4kHz versions were still discernible, but a bit easier to recognize through the DirectStream DAC.
Audio Research’s DAC8 is obviously blessed with a very good analog section; however, the DirectStream DAC’s passive output section was a bit more refined—something I wasn’t expecting.
In this review, I’ve explored the performance of the DirectStream DAC and compared it to another DAC of roughly similar price. Now it’s time to answer three important questions: 1) Does the DirectStream DAC live up to its claim of revealing hitherto hidden details in your CDs; 2) if the answer to the first question is yes, how much of an improvement in sound does the DirectStream DAC make; and 3) is it worth its price? Answer No. 1: Based on my listening sessions, I’d have to say that the DirectStream DAC does indeed retrieve more information from my recordings, from CD to the highest-resolution recordings, than I had heard from other DACs. Answer No. 2: The differences in sound were perceptible, and contrary to my expectations, not really subtle. The effect of a lot of previously unheard information being added to previously audible information was often surprising. On the other hand, I wasn’t surprised to learn that extracting more information from a recording is not always the same as making the recording sound better. Several times during the review period, I discovered that sometimes the DirectStream DAC made some recordings sound more obviously mediocre. As an audiophile, I suppose that’s good; but as a music lover, sometimes less detail may actually be a benefit. An unexpected advantage, though, was that I learned that quite a few CDs and rips sounded better than I realized; so for well-recorded material, it elevated the playback quality quite noticeably. I guess that’s all you could reasonably expect. Now for the hardest question— answer No. 3: This answer depends to some extent on personal preference. Although my memory of other DACs has faded with time, I can’t remember any DAC that impressed me as much with its overall sound quality as the DirectStream DAC. So my answer to third answer would be yes. Of course, your mileage may vary. Obviously, any purchasing recommendation must take into account your financial situation. A price of $5995 is pretty substantial, but I don’t know of another DAC at or below that price that sounds as good.
Whether you’re a rabid DSD fan, or have strong convictions that PCM is the only way to go, PS Audio’s goal for the DirectStream DAC was to make both types of recordings sound as good as possible. My personal take is that it substantially realizes that goal. I highly recommend putting the PS Audio DirectStream DAC on your must-audition list if you’re considering purchasing a DAC in its price range—or even if you’re willing to spend more, even a lot more. It’s easily the best DAC I’ve heard in my system, making digitally-recorded music sound better than I’ve ever heard it.
Bravo, Ted and Paul.
SPECS & PRICING
Converter type: Field Programmable Gate Array custom-programmed to serve as DAC
Sample rate (PCM): 44.1kHz, 48.0kHz, 88.2kHz, 96.0kHz, 176.4kHz, 192kHz
Word length (PCM): 16, 18, 20, 24 bits
Data rate (DSD): Standard (2.8MHz) or Double (5.6MHz) DSD on PCM on all inputs as well as raw DSD on I2S inputs
Synchronous upsampling, all inputs: 28.224MHz
Analog conversion method: Delta-Sigma, double-rate DSD
Output levels: “Low” setting, 140mV RMS unbalanced/280mV RMS balanced; “High” setting, 1.4V RMS unbalanced/2.8V RMS
Digital inputs: I2S(2), coax, XLR, TosLink, USB, Network Bridge slot
Balanced outputs: One stereo pair on XLR connector
Unbalanced outputs: One stereo pair on RCA connector
Dimensions: 17" x 4" x 14"
Weight: 22 lbs.
Price: $5995; $3995 with trade-in of PerfectWave DAC
4826 Sterling Drive
Boulder, Colorado 80301