by John Richardson

OK folks, this one is an ongoing saga here in the world of Part-Time Audiophile. Like a boomerang (or certain Millennial offspring) the subject of this review just keeps coming back again and again. Why? Well that’s an easy one: it’s different each time!

What would you say about a DAC that’s essentially future-proof? One that’s forever upgradeable in order to take advantage of future firmware developments in the digital realm? You’d like that, huh? Of course, it’s called protecting your audio investment.

Well then, I’ve got your digital dreamboat right here, folks, so step right up and see what it’s all about. That’s right, we’re talking PS Audio’s DirectStream DAC ($5,999) and its sidekick, the DirectStream Memory Player, (also $5,999).

Just so we’re keeping track, the DirectStream was last reviewed by Part-Time Audiophile back in 2015 — you can find that review here.

Got all that? Great. Let’s start with the DAC in the form I received it.

The DirectStream DAC as brought to you by Software Version Torreys

When the DirectStream DAC arrived here at my place, directly from Scot’s abode, it had the recent firmware version known as Torreys already installed. My assignment was to get acquainted with the DAC in its present configuration — and then upgrade to the newest firmware (Huron), so that comparisons could be made. I had a pair of Pass Labs XA60.8 mono amps on hand to break in, so I figured I’d use that task as an opportunity to get used to the Torreys version of the DAC. I also used my Zu Audio Dirty Weekend Omen speakers as part of the evaluation rig, as I find them eminently musical while still resolving enough to easily hear what’s going on further up the audio chain. In fact, the Zu Audio/Pass Labs combo just sings … but that’s another review entirely — stay tuned.

Without getting too technical, the DirectStream DAC massages data, and I mean intensely. As in “on the way to a Happy Ending”. Once we get to this level of massage, software plays a big role, to the point of being able to greatly affect the overall sound of the analog signal coming out of the box — this is where things start to get really interesting. Each version of software can sound drastically different from its predecessor, even though the electronic “guts” of the gear remain constant.

After a couple of weeks of letting the system run in, I decided that the sound of the amps had calmed down enough to get a good overall picture of the setup and its performance. First off, I’ll say that the sound I’m getting is some of the most involving that I can ever recall hearing in my home audiophile lair. It’s that good! There’s no hint of fatigue or strain as the music bellows forth from the Zu speakers; there’s plenty of sparkle, body, and texture, from top to bottom. This is a heck of a baseline from which to start, and I’ll refrain from saying much about the DAC itself at this point, as it’s only a single part of a wonderfully musical system where all the parts seem to be meshing together in almost perfect harmony. Making changes to the digital front end should tell me more, as we soon shall see.

The DirectStream DAC as brought to you by Software Version Huron

Alright then, Huron is the latest (and supposedly greatest) PS Audio DAC operating system, so load it I did. The cool part here was that the process was incredibly easy; no need to say more, as this dead horse has been well beaten here at PTA and elsewhere. The whole ordeal, start to finish, took me maybe five minutes. The only other thing I had to do while I was at it was to upgrade the DAC’s Bridge II interface to the latest version, which in cahoots with Huron will let the lucky listener stream Tidal and “unfold” MQA files to their highest possible resolution. The future has arrived, and it’s glorious.

As a quick aside, I was looking at some old issues of Art Dudley’s Listener magazine, and I found a prescient quote made back in early 2000 by columnist Peter Breuninger. Addressing the new millennium, as well as the beginnings of digital format wars, as predicted by the onset of SACD and anticipated decline of the compact disc, Breuninger told us not to worry, as soon, “all music will be downloaded onto a chip, and we will pay rights for time allowance and playback frequency.” How right he was, and here I am today digging every minute of it!

As for sound, once I installed Huron, everything just got bigger and bolder. I noted an immediate increase in bass extension and weight, as well as greater treble presence and definition. My first impression was that these two attributes took hold at the expense of the midrange, which seemed a bit reticent and more mechanical than before. Upon further listening, though, I think that’s mistaken. Perhaps it just took time for my ears to adjust to changes at the frequency extremes, but the midrange texture seemed to creep back in over time; the result is a robust, nicely-balanced presentation. Somehow, the DAC seems more “alive” than it did before, exhibiting more jump and excitement (truly excellent PRaT), but not to the exclusion of the previously smooth presentation that made the system so easy to listen to for hours on end with little hint of glare or fatigue.

Stereophonic images were full-bodied and well-carved into three-dimensional space. Everything in the soundstage was precisely located, just as one would imagine that it should be. In fact, if I were to use a single word to describe the DirectStream DAC as powered by Huron, it would be “precise.” The detail and spatial characteristics of the system were remarkable, as I’ve found that precise imaging is not necessarily the strong suit of the larger Zu Omen speakers.

I know Tidal and MQA have their detractors, but this system has helped make me a believer from a purely sonic point of view. Couple great sound with the convenience, vast choice of musical offerings in pretty much any genre, and attractive price of subscription, and you’ve got a winner. Oh, if you Tidal folks are listening, please, oh please see if you can get the rights to the ECM jazz catalog. I’ve enjoyed listening to Pat Metheny’s newer stuff for example, but I miss being able to hear his more classic albums on the ECM label.

Via the SoundStream DAC, Redbook, hi-rez PCM, and MQA files were all a joy to hear, either using my own files played back with Pure Music (Version 3.0.6) or with Tidal (with and without MQA). For example, it was fun to compare three versions of the Modern Jazz Quartet’s classic album The Complete Last Concert, which I can access from Tidal as both Redbook and MQA, and also as a digitally archived 24 bit/96 kHz needle drop of my own making. I could easily hear differences between the various versions.

While the Redbook sounded better than “just fine”, I got a really nice sense of richness — tone and glow — from the 24 bit/192kHz Master MQA file that (by contrast) seemed missing from the Redbook version. I can’t say whether there was more or less detail; the difference was more in the overall presentation and timbre of the music. My own hi-rez needle drop of the album, which sounds uncannily like the original vinyl, was far closer to the Master MQA version than the otherwise excellent Redbook file.

As for a converter comparison (or two), here goes. I have the standard (non-SE) BorderPatrol USB DAC ($995) here, and it’s a fantastic unit for the money. It brims with life and sonic involvement, and as Scot Hull says (of the SE-version), it tends to walk a bit on the wild side. Against the DirectStream/Huron combo, I found the BP DAC to sound a bit softer in the treble and bass, as well as less focused spatially. Even so, there’s something awfully beguiling and lifelike about its midrange presentation that just sucks me in that the PS Audio unit doesn’t quite match. Aside from that, the PS Audio is clearly the superior DAC with its precise and buttoned-down performance, as it should be for six times the money. It also goes without saying that the DirectStream is a far more capable and versatile machine for dealing with the myriad file types and resolutions encountered and treasured by many audiophiles today, as the BP DAC processes Redbook only.

Perhaps a more apples-to-apples comparison would be against my “house DAC”, an older Antelope Audio Zodiac with an expensive customized linear power supply. While not the newest technology possible today, I’ve found the Zodiac to hold its own both in terms of its sonic performance and its file processing capabilities. Interestingly, I found the Zodiac and the BorderPatrol DACs to sound almost identical in this system, with both sharing a blooming, almost billowy midrange. Again, the PS Audio DAC trumped both in terms of frequency extension and definition, and maybe edged both out in ultimate ability to retrieve tiny details.

Of course, the real advantage of the PS Audio system over both of the comparison DACs is its flexibility with regard to changing technology as well as its ability to handle the increasingly popular MQA encoded music files. These factors will likely make a big difference in many audiophiles’ purchasing decisions who are willing to pay the premium in price.

The DirectStream DAC as brought to you by the DirectStream Memory Player

One of the great advantages of computer audio (besides the convenience factor) is its ability to read a disc and get it right. In the case of a normal digital transport, the disc is read in real-time, with the bits flowing on to the DAC for ultimate conversion to the analog domain. The problem here is read errors: an on-the-fly reading doesn’t get everything right. If, however, a disc can be read and then re-read, a perfect bitstream can then be laid down temporarily and sent on to the DAC, albeit with a short time delay. This is exactly the approach taken by PS Audio’s DirectStream Memory Player, which in essence is the perfect hybrid between digital transport and permanent computer audio memory system, given its own internal solid state drive for temporary file storage. Another secret weapon in its arsenal is data transfer via I2S, a protocol that PS Audio claims has lower jitter (that is, sounds better) than normal coaxial or optical interfaces, and which can be accessed using an HDMI interface cable (vendor provided!) between the Memory Player and DAC. Toss in a bunch more exclusive PS Audio digital technology tidbits, and you’ve got a killer silver disc reader indeed.

I tried spinning examples of each of the different types of discs I have on hand: regular compact discs, SACDs, a clutch of Reference Recordings’ HRx discs, and even some of my homemade hi-rez DVD Audio discs of archived needle drops. The Memory Player had no trouble reading or playing back any of these, and all read at their native word lengths and resolutions. It took maybe 15 to 20 seconds to initially read the disc and get its contents transferred over to the solid state memory, and then playback could begin. This device is classified as a “universal player”, and I’m convinced that it can read pretty much any variety of digital audio file that can be presently stored on a polycarbonate disc.

Admittedly, it’s been a long time since I’ve spent time listening to spinning silver discs in a high-end audio system, but I heard results that are pretty much the same as those that I hear using sophisticated computer audio systems and big dollar media servers. To me, this proves the efficacy of PS Audio’s approach to storing the digital data temporarily on its own hard drive prior to sending it on to the DAC. The sonic advantages associated with obtaining a perfect facsimile of what’s on the original disc were apparent: less distortion, more fleshed out tone, and vanishingly small noise floor. All I can say is that if I were still in the business of spinning little silver discs, the DirectStream Memory player would most definitely be on my short list of audio things worth saving up for and purchasing. Of course, at $5,999 it doesn’t come cheap, but it could well be an end-game product for those who are so inclined.

Oh, and I almost forgot to tell you, but the physical act of pulling a disc out of its jewel case and placing it carefully into the drawer of the transport brought back a flood of pleasant memories stretching back to my high school days and progressing through my earlier experiences as a budding audio enthusiast. It’s actually been kind of fun.

Looking back, it’s been an enjoyable journey exploring and listening to this pair of digital dreadnoughts from PS Audio. I feel fairly safe in concluding that not only are these components highly enjoyable to hear and use, but that they are also safely on the cutting edge of digital audio reproduction. And I don’t see that premise changing anytime soon, what with PS Audio’s commitment to free software updates to anyone purchasing the gear. I don’t think the digital audio enthusiast could go wrong with this pair!