CAD 1543 MkIII DAC
By the standards of domestic electronics separates hi-fi is pretty hairshirt stuff, it takes up a lot of space, isn’t very easy to use and sounds its best with media that you actually have to pay for. In an age of instant access and inexpensive alternatives it’s remarkable that anyone bothers with it. Within the separates world there are those that seek to accommodate today’s short attention spans and desire for ease of use and those that refuse to pander to the casual listener and produce components that are totally purist in their design and execution. Computer Audio Design or CAD is very much in this camp, designer Scott Berry’s first product was the 1543 DAC back in 2012, this third generation version is pretty much identical in appearance and functionality. It has just one input (USB), one pair of single ended outputs and a fixed power cable; there is no more minimalist a digital to analogue converter on the market.
The CAD 1543 MkIII is a single purpose device constructed purely in order to get the best results from digital audio, specifically, streamed digital audio from a computer or dedicated streamer. If you want to upgrade your CD player this is not the DAC for the job. Its singularity is even more extreme when you look at the converter chips chosen for the job, as the name suggests these are Philips TDA1543 devices, ladder DAC chips originally created in the nineties before the 1-bit sigma-delta converter took over the field with its fabulous specs and massive bit rate and oversampling capabilities. But just as digital has not replaced analogue in many enthusiast’s systems, new old stock chips such as the 1543 have qualities that you will be hard pressed to match with a modern alternative.
The original CAD 1543 had 16 such chips onboard, the 1543 MkIII ups this to 20, the most that would fit inside the acrylic chassis, we are told. This doesn’t make the CAD any more capable in terms of accepted data rates, it’s limited to a maximum 24-bit/176.4 kHz and no DSD, but the extra chips reduce the noise floor, and as this form of noise is the limitation with all audio equipment and digital in particular, that is a good thing. The extra chips also provide a higher output current for the DAC (albeit this is still lower than usual) and drop output impedance, which means that there is less resistance to signal flow at the output. Most DACs have a separate output stage, a small amplifier in most cases but being a purist Scott avoids this and uses a Duelund capacitor to act as a low pass filter in order to block DC.
Changes have also been made to the power supply for the 1543 MkIII, this is now based around EI transformers rather than the more common toroidal types, this is something Scott discovered in high end valve/tube amplifiers from the likes of Audio Note Japan and Trilogy. Like-wise this DAC employs choke filtering in the power supply using custom capacitors from Japan. Both technologies were adopted for the usual reason of reducing noise and thus enhancing sound quality.
Another upgrade is to the feet, gone are the soft rubbery waffle feet of earlier generations to be replaced by synthetic stone Krion alternatives, which may have something to do with the more lively sound of this DAC. The first two 1543s had a super relaxed, earthy sound that was very appealing to some but may have been too laid back for others, for the 1543 MkIII Scott has chosen a more pacy and dynamic balance. This however is a relative state of affairs, CAD DACs will never be forward or eager sounding, still it’s an interesting change nonetheless.
What hasn’t changed is the use of an asynchronous USB interface which ignores the clock signal in the incoming data and uses a highly accurate internal clock. This interface has lower phase oscillators (the heart of the clock) than the earlier DAC and better galvanic isolation as well, what it doesn’t offer is universal compatibility. It works with virtually all Linux based streamers from the likes of Innuos, Auralic, Aurender and Roon but was not happy with my Lumin. Apparently Lumin have to make a small change to their coding to sort this but at the time of reviewing I had to use a different source, namely my Melco N10 server/streamer. This usually sounds a bit too soft and laid back even for me but here it proved a perfect partner.
CAD provided a GC1.1 Ground Control device and and Ethernet Controller in order to improve the sound of the Melco which doesn’t usually sound that great via its USB output. I already had a USB Control device in the spare socket and the combination of all these elements made this server/streamer sound significantly better. So much so that I have kept them in the system since the CAD’s departure. The final idiosyncrasy of the 1543 MkIII is the captive power lead, this is a high quality cable with a very decent mains plug and undoubtedly contributes to the impressive results I got with this DAC, but I can see some wanting the option to upgrade this key element. That said you get a complete product, one where the designer has control over every aspect except the signal cables, so what you hear is going to be pretty close to what he thinks is the ultimate result, source allowing.
Sound quality
The sound of this DAC can be summed up in one word: natural. All the effort that CAD has put into eliminating noise and interference of all sorts from the circuitry inside the 1543 MkIII and the choice of casework and supporting feet pay off with an uncannily relaxed yet highly revealing sound the like of which is rarely heard from digital audio. I used CAD’s USB II-R and Network Acoustics muon2 USB cables to hook the DAC up to my Melco and was rewarded with results that made albums sound much better than is usually the case. Brass instruments can often sound hard and edgy with digital audio but the 1543 MkIII manages to convey their acoustic brilliance without the glare that usually accompanies it. This is one reason why a lot of jazz sounds better on vinyl, that format has a smoother top end and no tendency to graininess, the CAD proves that it’s not the medium that’s introducing the problem but the way that the majority of converters reproduce it.
It meant that I was able to enjoy some very upfront music and not recoil from hard, bright leading edges. This included Dweezil Zappa’s remarkable interpretations, well covers to be honest, of his dad Frank’s music. With hardcore tracks like The Deathless Horsie sounding absolutely stonking thanks to the power and energy of the live performance, you can still hear the compression on the recording but that doesn’t get in the way of the brilliant musicianship. If the 1543 MkIII was merely relaxed it would not do this so well, it has an excellent sense of timing and strong dynamics. As alluded to above the earlier 1543s were super smooth and effortless but lacked a little get up and go.
This was perhaps because the digital sources at the time were not as sophisticated as they are now, dedicated streamers were in their infancy and many relied on PCs with their inherent noise problems. The 1543 MkIII was created to offer greater transparency and make the most of more refined sources, I don’t imagine that it would make a well sorted PC sound nasty but the key phrase there is ‘well sorted’. Eg running top notch playback software and minimising noise wherever possible.
The other area where the 1543 MkIII is a clear upgrade over its predecessor is in imaging, it can deliver an incredibly open, three-dimensional soundstage the like of which is rare from any source. I love the way that reverb seems to go so far back behind the speakers and that the better recordings can produce sound that totally surrounds the speakers on all sides. The speakers need to be good enough to show this as does the amplification but I wasn’t using anything too exotic, Dali Epikore 9 speakers notwithstanding.
Timing is for me the key to musical involvement and it’s here that the 1543 MkIII really hit home, with all manner of music it pulls you in and holds your attention by virtue of delivering the full tonal range in a coherent fashion. With its flat response digital has a theoretical advantage in this respect but it’s rare to find a digital system that can approach a good analogue source when it comes to timing. It must be something to do with the processing side of things, the CAD’s old school multi-bit technology does timing with precision and no steely edges. It reveals that digital to analogue conversion technology was ahead of what could be done with the spinning polycarbonate disc (CD), and that the steps taken in the converter chip world have not necessarily followed a musically superior path.
But it is foolish to assume that the actual DAC chips alone are the answer, implementation has always been key with any technology and you can see that CAD has gone to extremes in order to provide these chips with a very comfortable environment. I purchased a Bricasti M11 R-2R Classic DAC shortly before the 1543 MkIII turned up and was disappointed to find that it is not as good. There is a significant price difference of course and the Bricasti has a lot more features but I had still hoped that the CAD wouldn’t be so much better, unfortunately I was wrong.
Conclusion
The CAD 1543 MkIII is a remarkable digital to analogue converter, what it lacks in features and sample rate capability it more than makes up for with a sound that is more realistic, natural and engaging than the majority of the competition. If you can live without 192kHz and DSD, or, to put it another way, if you prefer to hear the majority of your albums at what must be extremely close to their very best, and have a source that can down-sample the few that this DAC cannot convert, then the CAD 1543 MkIII is a very tempting proposition.
It is also extremely well made and finished, there may not be any switches or knobs but this is because every switch compromises performance, this DAC is like an F1 racing car, built for one purpose and that is to sound exactly like the original recording, nothing apparently added nor lost in the conversion process.