Naim DAC Digital Converter (HiFi-Plus 71)

Naim Audio never made a DAC, in the same way that it never made a CD player. In other words, it doesn’t bring out a product just to fill a range or even because it’s fashionable to do so. It brings out a product because it can finally add something substantial to the line-up. Which is why Naim Audio has its first DAC.

The development of the DAC shows just how much commitment the company has to its future. This is a product designed to bring out the best in its computer-side sources (such as the HDX hard disk player tested last year, or with a plug in drive, any passing PC or Mac or even the much-loved and much-under-rated Squeezebox). That it can be used with a CD transport or an existing Naim CD player is almost a secondary consideration.

The DAC itself uses a pair of PCM1704K chips by Burr-Brown, a regular feature in Naim players. But before the data makes it to the DAC itself, the datastream is read into a SHARC DSP that acts as data receiver, filter for out-of-band artefacts and acts as a 40bit, 16x oversampler and a buffer. This is aided by a tin of salmon and a Blackfin DSP chip, which controls both USB and the DAC, and a reclocking gate circuit directly prior to the DAC chip (I’m lying about the tin of salmon). It’s also the first high-end DAC with an Apple Authentication Chip, meaning it will talk to iPods and iPhones.

Cleverly, the DAC makes jitter a thing of the past, without resorting to asynchronous sample-rate conversion. Instead, it references the datastream to one of 10 fixed frequencies and the SHARC chip picks out the right oscillator to clock-lock the signal. If the signal doesn’t fit one of those 10 frequencies, then it falls back on ASRC. Naim did this by hiring a pair of the sharpest-tool-in-the-box mathematicians to write some extremely elegant code.

The key thing to the DAC is its simplicity, inside and out. That being said, the five buttons on the front make it one of the most button-heavy DAC out there. These can work to control the files on a USB thumb drive, or select one of eight S/PDIF and additional USB digital inputs on the rear panel. The DAC’s big feather in its cap (aside from the uniqueness of it being the first DAC from hitherto DAC-deniers Naim) is it can handle recordings at a sample rate of up to 768kHz and at 32bit resolution. Of course, you have to ask whether this makes a difference to mere mortals armed with 44.1kHz, 16bit CD files transferred to computer, but it suggests that Naim’s own music label is going to start moving from big high resolution downloads to really big, really high resolution music downloads soon.

But forget the sort of high-res files that only studio engineers can get a hold of right now. How does it sound with regular music, off regular music CDs? Jolly damn fine, really. It’s immediately obvious and recognisable as an upgrade of the first water. It’s obvious because you listen to something played perfectly fine without it, play the same thing with the DAC in place and wonder how you could ever live with the sound you had liked or even loved a minute or two before. It’s more three-dimensional, more detailed, more transparent, more musical and most of all more likeable than before. That doesn’t mean they were ‘nice sounding’; play a piece of music that was rough-edged and it sounds just as rough-edged, but you want to listen to the music more.

A key recording that demonstrates all of the above is ‘Butterfly’ by Jason Mraz. It’s a wry, deliberately syrupy-soul track with some of the most dodgy (and downright rude) sounding lyrics you’ve heard since the 1980s. And on through the DAC, those lyrics stopped sounding like soft-core porn and started sounding like sarcasm. Other tracks were given the same treatment through the DAC. It just gets more out of the music. Whether you flipped between DAC and no-DAC within a single track or spun out whole albums, the difference was clear and hard to live without once heard.

But there’s that other great Naim concept, too – the upgrade path. Adding in a beefy power supply adds a lot more to the performance, although curiously I’d say more in the ‘audiophile’ direction than necessarily the ‘Naimophile’. The upgrade gives even more image space, solidity and separation and could get even the flattest of flat earthers starting to talk about micro-dynamics. The improvement is noticeable and significant, although it must be said so is the hole that added power supply makes in your bank balance. The upgrade doesn’t have to happen at time of purchase and is an easy fit (simply remove the Burndy plug protector and connect in the PSU, the power feed to the DAC remains in use), allowing you to buy a five or even seven grand DAC in stages.