The Pro-Ject Pre Box S2 Digital… the little DAC that could!

What…!? A digital product? What’s happening here!
Yes, while it’s true we are serious vinyl fanatics here at Rich’s we also appreciate bits & bytes. Digital formats like CD’s, downloads, and streaming can also be great music formats especially when they’re processed well and listened to through great associated components, just like vinyl. One of the most important, if not THE most important part, of the digital playback chain is the Digital to Analog Converter (DAC). As usual, a little history may be in order here to help you understand why DAC’s have become such a ubiquitous component in the audio world. Let’s Face it, it seems like almost every manufacturer of audio gear has at least one or two models in their line up. So, let’s go back to about 1982…

What happened in 1982 you ask? Well, our friends at Sony and Philips worked together and introduced the Compact Disc (check out my article “Why Vinyl” for a few more insights). “Perfect Sound Forever” was the marketing tag line. However, audiophiles and music lovers alike found out quickly that something wasn’t right. Although CD’s had great signal to noise ratio, low distortion and great bass definition, they were hard sounding, strident, fatiguing, and “glassy sounding”. This was especially true in the second and third generations of “improved” players (remarkably, some of the original Philips and Sony first generation players actually sounded better and are still sought after by some folks). The CD brought lots of advantages from a portability standpoint and the music industry embraced them heartily and quickly ramped production and sales of CD’s as the ultimate media for music. Still, the hi-end audio world was trumpeting the fact that there was something that was just “off” about tearing an analog musical signal into pieces and reconstructing it with the expectation of it being “right”. So, after some time and investigation, the culprit appeared to be a piece in the chain that few people knew much about, and that was the Digital to Analog Converter… the DAC.The first monolithic (in the high tech electronics world, “monolithic’ usually refers to some device or process that has been reduced to a single chip or “device”… think of the processor in your PC or Smart Phone) DAC came from the Burr-Brown research team inside of Texas Instruments in early 1982. The PCM53/DAC7000, being the first DAC “chip”, was what actually made CD playback possible and was the last link in the chain that allowed Sony and Philips to release their players later that year. The PCM53 conformed to the “Red Book” standard that Sony/Philips established to govern CD recording and playback.1 It was the part of the chain that put all of the digital bits & bytes back together to create an analog signal that could be amplified and sent to your audio system. Isn’t it interesting that the thing we’re ultimately trying to accomplish with digital media and digital music reproduction is to get it back to an analog signal? And, that is what audio engineers, designers, critics, and music lovers of the day figured out was a problem; that the DAC in early players was where the downfall was at. So, in 1988 another momentous occurrence happened – the release by Arcam of England of the Black Box, the first external DAC made commercially available. Now, you have to have a player that allows output of the digital bitstream to an external DAC for it to actually do anything, and luckily there were some players at the time that had digital outputs that were originally marketed as a conveyance for looking at pictures or streaming computer data from your CD player. I don’t know of anyone that ever did that, but luckily, having those digital outputs allowed the external DAC to be born.

Over the ensuing years, DAC technology went through huge changes, with manufacturers of players and DAC chips constantly racing to ever greater technological heights to create DACs that would improve digital sound. Over-Sampling, Non-Over-Sampling, 16 Bit, 20 Bit, 24 Bit, One-bit, 96Khz sampling, 192kHz sampling, 196kHz sampling, DSD (Direct Stream Digital), HDCD, MQA encoding, etc., etc., etc., all of which created incremental improvements in digital sound. Today, the DAC has become a ubiquitous component in digital playback, even with the steep decline in design and sales of CD players. Streaming and computer based audio are still driving DAC technologies to better and better quality levels. Today, a good DAC can make a huge improvement in digital sound and many times rival analog in all but the last bit of detail and warmth craved by so many analog aficionados. Which brings us to the focus of this review (finally!); the Project Pre Box S2 Digital DAC/Preamp.

Pro-Ject is one of the largest manufacturers of turntables in the world, and we carry many of their models here at Rich’s, like the Debut Carbon and the RPM-1, both of which are insanely good values. Pro-Ject does OEM work for other companies (you’d be surprised to find out how many turntables in the world have parts form Pro-ject in them!), and also manufactures an extensive line of electronics like phono preamps and headphone amps. Pro-Ject is continually adding to their line with more and more products and has recently branched out into many that are digital in nature, including the Pre Box S2 Digital… which I’ll call the PBS2D to keep it simpler to type!. The PBS2D is quite a remarkable little unit, especially when you consider what it does in relation to its size. The old saying that good things come in small packages holds true here. The PBS2D is smaller than a CD Jewel box and only about as tall as a couple of decks of cards, yet it has full DAC capabilities for almost every format you can think of, including Hi-Res Playback up to 32 bit 768kHz, DSD up to DSD512 and it’s both MQA and Roon ready. Now, if you already know what all of that is about, you’re well versed on digital music technology, but if the opposite is true, don’t feel bad, the world of digital music contains is a dizzying array of technologies. Suffice it to say, that this little box does more than some units two and three times it’s size as well as two, three, or even four times its price. And here’s the really cool part; it sounds fantastic!

The PBS2D has been getting raves all over the audio press, so you don’t have to just take my word for it. The cost to performance ratio for this DAC is just off the charts. Not only is it a full fledged, high end DAC, but it also has selectable digital filters, multiple inputs for coax, optical and USB, a headphone amplifier (great with a pair of Grado’s!), and it has a volume control so that you can utilize it as a preamp as well. A dizzying array of features in a package of this size and price. The heart of the unit is a fully dual mono design utilizing the ESS 9038 Sabre DAC. ESS is building what are arguably some of the best DAC chips available today, and you will find them in many, if not most, ultra high-end DAC’s that can command 5 figure prices. Project has implemented the ESS Sabre technology into their PBS2D with excellent results. I put the DAC into my system at home for about 3 months and found it to be a musical as well as a user friendly performer that surprised me at every turn… and as long as I’ve been involved with audio, little surprises me anymore!My system included a Rogue Pharaoh integrated amplifier driving Acoustic Zen Adagio speakers, all wired with Acoustic Zen Copper Reference interconnects, Hologram II speaker cables, and Tsunami and Gargantua power cables. Digital tracks were all played via my Apple iMac music server with Roon software networked with an Aurilic Aries Mini streamer, or my Oppo BDP-105 player via Acoustic Zen Absolute digital coax. All of the tracks that I usually assess gear with sounded exceptional in every possible way. Dire Straits Industrial Disease from “Love Over Gold” is a standard for many audio enthusiasts and it did not fail to please through the PBS2D. Dynamics, speed, exceptional tonality and an outstanding representation of instruments in the room with bloom and space is spot on. Mark Knopfler’s guitar work is, as always, a delight here, as it is in almost every recording he’s ever been associated with (Knopfler is well known as a stickler for great sonics), and I realized after listening to the aforementioned cut, that I listened to the rest of the album, which is always a great sign to me that the equipment I’m listening to has allowed me to quit worrying about circuits and DAC’s and speakers and electronics, and just lets me listen to the music. The same experience kept happening with cuts from Norah Jones, Jane Monheit, Peter Gabriel, and Pink Floyd. All emerged from my system with beautiful size, space, realism, timbre, and tonal correctness. Miles Davis’ Kind of Blue, the biggest selling jazz album of all time, sounds big and in the room via the PBS2D, which is a feat that I can tell you from experience, some DAC’s just can’t get right. Beyond the compositional and performance genius found in this album, there is a certain presentation of the studio venue that is uncanny in its realism, but many lesser systems can’t flesh that out. Listening to some of my favorite classical CD’s via my Oppo player, like Haydn’s “Creation” or Beethoven’s “Symphony #6”, “Scheherazade” by Rimsky-Korsakov, or Scriabin’s “Spartacus” allowed me to hear deeply into the music, maybe even a bit more than through the excellent DAC that’s built into the Oppo. Now, I’m not a huge headphone guy, but I did check out the PBS2D’s headphone capabilities with a pair of Grado SR80’s and the sound was warm and musical with that great “in your head” image resolution that only ‘phones can give; a nice addition to this little DAC!

One of the things the Pro-Ject DAC affords the lucky owner is the ability to check out “Hi-Res” formats and MQA recordings. Without going too far down the rabbit hole on digital formats and whether MQA is just another chapter in the format saga or the holy grail that digital recording needs, let me just say that some of the higher resolution formats out there do sound really good, and this small but mighty DAC gives you the ability to check them out if you have ever wanted to and just didn’t have the means previously. Hi-Res DSD and MQA capabilities are built in which are usually only found in much more expensive units. Because of the PBS2D, I was able to dig into the Tidal catalog and try some MQA files. To this listener, yes, they sound better! More lifelike and with a definite improvement in front to back image depth and instrument “size” within the space. Will MQA stick around and really become a format that will revolutionize digital? I don’t know. But, the point here is that for very little dough, you can wrap your hands around a product that will allow you to experiment and hear for yourself. On top of all that, you can even adjust the digital filtering types to tailor the sound (all digital playback devices utilize some form of filtering), and figure out what may be best for your room or desktop setup. It also includes a handy remote control and a beautiful OLED display that is crisp and clear, but is maybe a little small from a few feet away, but hey, consider the overall size of the thing.

As a comparison, I did some AB tests between the PBS2D and my Wyred 4 Sound DAC 2. Did the PBS2D best the W4S? No, but the W4S DAC is almost 4 times the price, so it should sound better, but the little Pro-Ject is right in the race and sounds better than it has any right to. The W4S sounds ever so slightly warmer and bigger, with a bit more detail and punch… but the difference is very slim. The bigger, more expensive DAC benefits from a bigger, more robust power supply where the PBS2D uses the “wall wart” variety, and the W4S has a more highly refined output stage I’m sure, but the Pro-Ject DAC is so close in performance that the difference in money makes one stop and think, “do I really need to spend more?”. I have found the diminutive yet formidable Pro-Ject Pre Box S2 Digital to be a true contender in the “giant killer” audio arena. Ready for the best part? You get all of this performance; Dual mono design, ESS Sabre DACS with selectable filters, multiple digital inputs, preamp capability, DSD, MQA, and Roon ready, and a great built in headphone amp, for…. (wait for it)…..

$399.00…. You heard that right, $399.00! I’m not sure that I know of ANY audio product available today at that kind of a price point that affords anywhere near the features, performance, and just pure musical delight that Pro-Ject’s Pre Box S2 Digital gives you. I’d imagine there are a LOT of DAC manufacturers out there today that are scurrying for their slide rulers to figure out how to compete with this little gem. Considering the price point, and what you get for your money, it’s almost criminal to NOT buy one and give it a spin! You don’t want to miss this!

Tim

1.Interestingly, the “Red Book” standard originally established by Sony/Philips of 16bits and 44.1KHz sampling is still the standard baseline for digital recording and playback. I could get a lot more in depth and technical, but I’ll spare you!