When I first lay eyes on the BMC PureDAC I saw it as a thing of beauty, in fact I misread the price tag next too the unit and saw it as 11 grand more than it is, and strangely didn’t even question that at the time. It was only when I took a second look at the unit at the Bristol Sound and Vision Show that I got excited and personally interested. The show had plenty of DACs, some cheap, some with prices sky high, some as simple as it gets, some with crazy feature sets and quite a few with headphone outs. Now being a headphone guy you’d think that all the DACs with headphone output would get me exited but the truth is, more often than not, the headphone outputs are last minute additions and are pretty abysmal, I mean the one of the TEAC UD-501 was unusable and even those on the expensive Antelope Zodiac Gold left me disappointed so I normally don’t care if they have one or not and put DAC capabilities first, to use with my dedicated headphone amplifiers. However when I saw the PureDAC didn’t just have the usual run of the mill ¼ inch headphone jack but the addition of a 4pin XLR output and they were showing it off with a Beyerdynamic T1 that had been recabled to be balanced, I could help but smile and get stuck in and boy from that first listen then with both their balanced T1s and my balanced HiFiMAN HE-500s I had brought along, I was impressed, and don’t forget, at that point I was still in the mindset this was £11290 product instead of a £1290 one and too keep up that illusion even after trying it, isn’t an easy feat although I was of course in substandard show conditions.
With the Questyle CMA800R
Before I start ranting all about the PureDAC, what it does, how it sounds and the rest of it, lets have a little look at BMC, the creators of this device. BMC are based in Germany and just look at their entire product line up because it shows they are believers in something their nation is renowned for and that is top quality products. The team there is run by Carlos Candeias and before BMC, they developed and OEMed products for a number of well named brands and that eventually led too them deciding that they would like too do their own thing (I make them right) and so BMC was born. I have kept putting BMC but it is actually B.M.C and it stands for Balanced Music Concept and this philosophy goes directly into their designs, maybe explaining why the decided that their product would incorporate the balanced headphone output and have such a balanced sonic signature. The company has a huge range of products including some much higher end stuff and the PureDAC is actually part of the more entry level, Pure line, which is forming into a very complete range of products at a quickening rate. Along with some stunning looking products and a great philosophy I also like the detail they go into describing the different technologies in the products and like there name, the technologies are also broken down into acronyms and it makes them very clear and easy to understand and as someone who only understands the basics of how things work but not a whole lot more, that turned out too be really handy.
This behemoth of a product is a DAC, Pre-Amp and Balanced Headphone amplifier and has a very cleaver design that keeps everything simple to use. On the back you have your digital inputs (the standard AES, Coaxial, Optical and USB), BMCs own BMC Link system for using this directly with other BMC products through two optical connectors, your analogue line outputs, both RCA unbalanced and XLR balanced and of course your standard power supply socket. The front is laid out very intelligently with you having a center circle with all the information displayed on in the middle and then too the left you have the DAC/Pre-Amp control panel and then on the right you have everything too do with the headphone outputs, oh and a very cool touch is that it also resembles the BMC logo, a rectangle with a circle in the middle. For both functions you have volume rockers (on the DAC side you can set the volume to 59 for a true line out) and a mute button (so you can mute both sides together or one at a time, which is really handy) and on the left you have the power switch and input selector while on the right you have the two headphone outputs. When powered off the front display is just an arrangement of buttons on an almost mirror like background and it is only when you power it up you get the display appear and I really like the bright white of the writing. In the middle circle you get the volume setting of both sides as well as the sampling rate that it is running and this can do all PCM files up to 32/384khz and DSD files as well so in other words, anything you can possibly throw at it.
As I said earlier BMC love their acronyms and with the PureDAC we have plenty, there is DIGM, LEF and DAPC. DAPC is all about the headphone amplifier section and it stands for Digital/Analog Power Converter. What it does is really quite clever. Basically the PureDAC is completely without a headphone amplifier section, instead the DAC goes straight too a uniquely designed I/V converter too generate the voltage needed for your headphones. Talking to the creator, Carlos, this is all very beneficial for some simple reasons. First of all the fact that the headphone amplifier doesn’t exist is just better, you have less signal path, less circuitry and just less things to get in the way and potentially cause trouble. Principles are similar too that of cables were no cable is better than the best cable. It also bring into use yet another acronym and that is CI, which stands for Current Injection and this is a technology in their I/V conversion which is in their words “virtually lossless” and leads to very low distortion. Now LEF moves directly on from DAPC because an I/V converter on its own isn’t going to be driving your headphones. LEF stands for Load Effect Free. The structure is used is best explained by them so here is what BMC say on the matter:
“The voltage source controlling the headphone with a very low impedance generates no distortion since it does not have to deliver any current to the headphone; thus the output device’s non-linearity doesn’t matter. The current is coming from a separate source and is not directly related to the music signal rather than the actual current demand, which is the music voltage divided by the complex and moving impedance of the headphone. LEF delivers current regardless of the phase and is superior in controlling a dynamic headphone. Due to the very low distortion of this circuit a feedback loop is not required. “
The way this delivers current into the headphones is more on task, as they say for dynamic driver headphones; examples Carlos uses are the Beyerdynamic T1 and Fostex TH900. He also says that headphones that are low in efficiency such as my HiFiMAN HE-500s are not as technically hard to drive such as something like the T1 and that’s why the T1 rarely sound as good as they do on the PureDAC, which is an opinion I can second. In terms of driving stuff that isn’t efficient like HE-500, well the PureDAC still puts out a very hearty 1.2 watt per channel in 32 ohms and it drives my HE-500s at an amazing level so they have that covered as well. Lastly you have DIGM, which is their Discrete Intelligent Gain Management that allows volume control in the analog domain without an amplifier section. Basically the I/V converter ratio is variable so this is where the volume is set. It allows for very low noise and great stability and as gain is at play, it allows pretty much any headphone, inefficient or the most sensitive in the world, to be used at the right gain, its like a smart device. Onto the different headphone outputs and I have already mentioned you have a 4 pin XLR balanced output and then a ¼ inch single ended output. Well lets just say the ¼ inch jack is just there for the more casual care free sessions and not for those looking for the top performance because this is a lot better balanced and generally a bit of a slouch single ended. BMC are also open to admit this with the balanced output impedance being very close to 0 ohms and the single ended output impedance being 100 ohms so its going to cause a lot of problems through that alone. I checked them both out and there was such a clear difference I have not gone back too the single ended since. DAC wise, BMC use a DAC chip from Sabre who I have been very impressed with lately in terms of performance but strangely this doesn’t use the flagship 9018 chip that some cheaper products do but a chip from another line of their products, the 9016 but I will say again that I don’t get too worked up about what chip a DAC is using.
The design of this is far from ordinary and far from what you expect at the price range. Its nice to see a product that not just stuck in the more generic metal block and looks just like most other DACs. This thing is huge but at the same time I think its very attractive and it also has a great presence, on that oozes that its here for business. The build quality is very tight with it being vented on the top for airflow and even rubber corners, in case it bumps into things? The only bit I am not a huge fan of is the masses of screws that jut out all over the place on it, I know they have too be there but they could be a bit more subtle. The 5 feet that it has are hench, give it a good height and seem too be better quality than any other components of mine. You also get an included remote that has all the functions the faceplate has, I have always thought it was really nice but when I got the Antelope Zodiac Gold through with its all metal remote, the plastic of this left it feeling inferior in quality. That being said it does the job, oh yes and the remote is backwards in that the headphone is on the left and the DAC section is on the right on the remote whereas it is the other way on the unit, its confused me enough times when you go to control it blindly.
BMC PureUSB1 Cable
I have tested the sound quality of the PureDAC as two devices, as a DAC with my range of my headphone amplifiers such as the Yulong A28 and Questyle CMA800R and then as an all in one DAC and headphone amplifier. For the most part I used it with my iMac running Audrivana Plus and using BMC PureUSB1 USB cable that actually has an active circuit box built in that removes noise and it does right next to the input so it doesn’t matter how long the cable is, you wont have sound quality deterioration. Although I used USB the most because that’s how it supports all my music files, I did try using a coaxial cable from the de-jittered output of the Antelope Audio Zodiac Gold and found a much more pleasing sound in general so I can conclude that I preferred the sound via coaxial but I did not find it worth scrapping the ability to natively play DSD and files above 96kHz for.
So too start off we have its use as a straight up DAC, using the balanced line out and then plugging my headphones into a dedicated amp. It completely holds its own acting as just a DAC and it has a brilliant tonal balance and a very natural sound that’s smooth with nothing poking its head out or getting in trouble. Everything is tight and very controlled, in fact the control is sometimes a bit too good with it seeming like it’s a bit over cautious but very rarely do a find that, the control comes in handy a lot and lets it keep on top of everything that is happening. The sound is just very clear and crisp, not coloured in any way and just a little bit on the lean side but it’s never came across as clinical or dull. It delivers impact in the bass, a real airy open vocal with great clarity in the upper registers and an extended, crystal treble. If I am honest one of the areas it didn’t always impress me as much with was in its depth of soundstage, where it just didn’t always capture what the recording could do but with DSD files, the soundstage managed to become more captivating.
As a DAC I compared it too a few and in general found it too do vey well, it was more bodied, dynamic and generally more pleasing than the similarly priced, DAC only, Rein Audio X3-DAC, it had a more balanced presentation with less bass power and warmth than the TEAC UD-501 and the difference in signature was more clear than any technical differences, with the signature being the factor you should consider more than anything else in this comparison. The only DAC that I felt really come through too put it in its place on pretty much all fronts, especially body and soundstage was the Antelope Audio Zodiac Gold, which is considerably more expensive and it still didn’t even do as good job with DSD as it does not have native playback.
Lets not forget who we are though and that is a headphone site at heart and when an amazing DAC has a built in balanced headphone amplifier, we use it, and I have been using it with everything, due too a very handy Double Helix Cables Ultrashort Adapter that allows me to use all my Kobiconn balanced cables with the 4 pin XLR output so I have used IEMs, closed headphones and my desktop headphones to really get to know the headphone output. However the adapter came some time into my ownership of the PureDAC so at first, my only 4 pin XLR balanced headphone was my HiFiMAN HE-500, known for being notoriously inefficient and hard to drive due to its planar magnetic driver. This is as good a test as any (well, other than the HE-6) too see how powerful a headphone amp is and this delivers a great performance with my HE-500s and I am not talking one that leaves you thinking, well, I guess it does ok, but one that leaves you with a grin and thinking, that some of nicest sound I have heard from my HE-500s. So while I await the adapters and cables I am sitting there avoiding the single ended output and thinking that the balanced output is very powerful, good for harder to drive stuff but likely noisy. Now I should have had more faith in the DIGM technology because it works a treat, whatever headphones, CIEMs or IEMs that I plug into the balanced output I find myself impressed by a black background and precise volume control, DIGM works a treat and makes it such a versatile device, not something I can say about a lot of stuff with great sound quality such as my Questyle CMA800R, a dedicated headphone amplifier that sounds great with hard to drive headphones but hisses loud with IEMs and low impedance cans like my Beyerdynamic T5p, which sound a treat off of the PureDAC. Basically what I am getting at is regardless what headphones you’re using, they wont be too much or too little or too anything for the PureDAC, it will cater for them.
With the Vision Ears VE6 XControl in balanced with the Double Helix Cables Ultrashort
Coming pretty much directly off of the DAC, the amp does take the same clean flavour. Its just right sounding, it doesn’t have the most expansive soundstage or the biggest bass impact or the craziest dynamics but it sounds real with a lack of exaggeration of any kind. Listening to Otis Redding’s “(Sitting on) The Dock of the Bay” in DSD through my ZMF Headphones V1 captures Otis’s silky voice and has the music flowing around it so effortlessly. Now it is not overly warm but it sounds organic and real, the reason I love DSD so much. Moving onto some Nat “King” Cole, still in DSD and spotlight is still on the vocals but the orchestra is full and well positioned around him, not in the most expansive away but pinpointing instruments is an easy task. It is of course not limited to DSD so jumping down to a CD rip of Bastille and listening to their “Oblivion” and I am still hanging on to every miniscule detail that is presented, with Dan Smiths voice being strong and airy with his slight underlying rasp being presented almost as accurately as when I saw them live. Switching up the tempo a bit to something more textured and fast paced so i put on some Thirty Seconds to Mars and was further surprised at how well it was still able to distinctively separate the different goings on. Each track I go through the more obvious it is what this device is doing and that is presenting the music very cleanly at a great speed and with an uncanny tonal balance, one that is perhaps unbeatable. It just lacks the scale it playbacks on compared to others. I get impressed again and again how the note decay seems to be spot on, it is never slow but I never find myself disapproving of how fast a note is either. I think when you bring the headphone amplifier into the mix everything really is pushed on, the DAC is great on its own but with the amplifier everything just comes together, it is synergy that the DAC and other DACs are never going to have with a dedicated amplifier and that is why the performance of this as an all in one unit feels so complete. Obviously for some things like my Sennheiser HD800 or HD580 I am going to recommend you stick too a dedicated amplifier but for headphones like my HiFiMAN HE-500, Fostex TH900, Beyerdynamic T5p, ZMF Headphones and even my CIEMs like my Lear LCM-5 and Lime Ears LE-3 (which sound bigger and better than I have ever managed on my portable gear) this is doing phenomenally and I can recommend you pick this up and not have to worry about investing in another amplifier because finding some better is going to cost a lot and not be easy.
With the HE-500, TH900 and HD800!
The PureDAC seems like its offering too much, you get impressed by the DAC, then you realize that has an amazing sounding balanced amp section that unlike most built in amps doesn’t leave me running too a dedicated one and they have the sheer beauty and prowess of its design along with its unholy versatility. At £1200 I am not only surprised to find something doing so much but also doing it well and for those looking for a great DAC or an all in one headphone unit, this has seems to be a step ahead