Reviewer: Frederic Beudot
Financial interests: click here
Digital Source: Auraliti PK90 USB file player / SOtM sDP-1000EX, Burson Conductor, Mac Mini/Audirvana, Accuphase DP55
Analog Source: VPI Scout 2.0, Dynavector 10X5mk4, Lounge phono preamp
Pre-amplifier: SOtM sDP-1000EX, Burson Conductor
Amplifier: FirstWatt F5, Triode Labs EL84TT integrated
Speakers: Ocellia Calliope .21 Twin Signature, Rogers LS 3/5a, Zu Essence
Cables: Zu Varial, Ocellia RCA cables, Absolute Fidelity speaker cables
Power Cords: Zu Mother, Ocellia power cables, Absolute Fidelity power cables
Powerline conditioning: Isotek Nova
Sundry accessories: Isolpads under electronics, ASI resonators and sugar cubes.
Room size: 21’x13’x7.4’.
Review component retail: Auraliti PK90 ($949) + Linear Power ($399)

Over the past decade, my digital journey has probably been no different than the one traveled by most our readers. Starting with increasingly higher-end CD players which in my case culminated in the Accuphase DP55 still used as a transport when needed, I then got lured into the SACD promise of digital convenience without glare. I owned or used on loan some of the best machines of the time, like the Esoteric X03se and the outstanding but to me unaffordable Esoteric P05/D05. Although SACD delivered on some of its promise, the remaining reliance on real-time access to disc-stored data and the mechanical imprecisions associated with spinning and reading said disc really made me aware that no matter how much money I’d throw at it, the technology was asymptotically converging towards a dead end. So-called memory players and the increasing use of DVD-player mechanics to enable multi-reads of the same data did provide a view of what things could be if we moved away from a playback process involving any kind of mechanically moving parts. The following years saw the explosion of computer audio in many forms. This followed divergent paths as is always the case when a new frontier opens up. I remember quite well my first review of a Weiss Firewire DAC and getting the distinct feeling that somewhere down the road, this would be the way to greater accuracy. The Weiss suffered its share of challenges as any of those early DACs did: dedicated drivers, not necessarily well-understood jitter sources and the impact those timing errors could have on a reproduction process that was in reality not all digital. The demise of Firewire precipitated by Apple who—then champions of Firewire over USB—moved to Thunderbolt instead forced the industry at large into the unique direction of audio over USB. This in turn allowed significant advancements like asynchronous data transfers where the computer does not dictate (and interrupt) the transfer rate or timing of transfer to the DAC, significantly reducing one of the primary sources of jitter. Later came higher data density, allowing for more accurate digitalization of analog masters and less destructive filtering of reconstituted analog waveforms. Couple that with the development of more and more powerful chips with all manner of digital filtering built in; the rebirth of non-oversampling yet high-resolution capable circuits; advanced chips and FGPAs; and you have a fairly good idea of the leaps and bounds which transformed digital playback in just the last five years.

I would be remiss if I did not throw a few more items on top of this admittedly very incomplete list. DSD over USB is one of those latest additions which leaves many split about whether it is a marketing gimmick meant to extract more money from us foolish audiophiles; or a true advancement. I can say that I sit squarely in the middle on it. I love classical music. When I can get my hands on a DSD recording or quality transfer from tape, I often but not always hear an ease and a naturalness that I don’t quite hear in very high-resolution PCM files. It is not about more detail, more space or better imaging. It is about that very elusive sense of flow and ultimate lack of stress. Or maybe it is all in my imagination.

Finally and significantly worthier of the effort, at least to my mind, is the advent of cheap high-capacity solid-state hard drives. Back to where I started, the Holy Grail being able to play back music without any moving mechanical parts, conventional hard drives remained up until recently the last area where we missed this ‘ideal’ state. Mind you, I don’t believe spinning drives to be less accurate at retrieving data and passing it on; but they inevitably contribute internal mechanical and electrical noise, some of which finds its way into the DAC. My own experience says that one can minimize this issue by storing the music on an external drive and connecting it to the computer through a different port than the one used for the DAC. For example, for years I ran external Firewire drives into a Mac Mini for playback through USB. Nowadays I would strongly advise to use Thunderbolt hard-drives with a Mac instead of USB 3 drives. Of course if you build your own computer, there are ways around this issue, namely using separate USB cards for input and output and using an audiophile-grade USB card with its own linear power source to connect to the DAC.

Or, you can start thinking of a different way to tackle the same challenges. Computers from mainstream players are really not meant to play music. Some, like a fully loaded iMac running dedicated software or a custom-built PC with JRiver can get you quite close but ultimately, there are still hundreds of unnecessary processes running in the background to disturb playback. You can come close to eliminating the effects of such processes by using a computer with so much processing capacity that their very existence will not interfere with playback. But that comes at quite a high price, be it PC or Mac. And you still need programs like Audirvana to ensure that music is treated as a priority and non-critical processes are shut down. If you don’t believe me, program your screen saver to come on 5 min. after you start playback and see if you don’t get a few dropped bits. What those programs will not address is the fact that each time Apple or Microsoft update their operating systems, you will likely need patches, updates or even costly upgrades to all your precious software. As PureMusic 3.0 rolled out recently, many users can attest that the first interaction with OS X Yosemite did not quite go as planned. Since Apple released OS X El Capitan a week later, one can expect compatibility issues to continue for a while longer. Don’t think that I am picking on Pure Music. My exploration of music servers came as a direct result of Audirvana completely stopping to operate when I updated my Mac Mini to OS X Yosemite. This is an industry-wide problem. Although programmers have become very adept at issuing fixes for all compatibility issues, it remains a never-ending game of playing catch-up.

Which, following my meandering path through memory lane, finally gets us at today’s topic. After my 2011 Mac Mini started acting up and Audirvana quit  on me, I was faced with the dilemma of either buying yet another super-specified Mac and getting a license for the new Audirvana; or look for alternatives. As I was doing due diligence, I laid down a few criteria of my own. First, being completely non-geeky, I wanted a solution that would not require taking two semesters at a community college to learn Linux or network setup before I could play music. Second, I wanted the option for SSD drives at manageable cost connected to the device itself, internally or externally. My home WiFi network is quite stable but I don’t trust it to stream high-resolution files wirelessly from my office where the modem/router is located to the music room at the other end of the house in the basement. I also wanted no-fuss DSD playback in case I acquired a DSD-capable DAC at some point in the future. Finally, I wanted a solution that I could expect to be somewhat future-proof—nothing being forever in the computer world—which offered flexibility in terms of playback controls. And of course, I was expecting my perfect server to be cost effective.