Naim Audio DAC review

Some 20 years after the first stand-alone DAC – the Arcam Black Box – appeared, Naim Audio has finally joined other manufacturers at the party.

For years, the company ignored external DACs completely, but with today's proliferation of digital media and music that does not come stored on silver discs, it is no longer an option. The DAC is fast becoming a must-have component in any contemporary hi-fi system.

The price of the Naim DAC pitches it well above budget favourites such as the cambridge Audio DACMagic, but comfortably below the high-end Chord Indigo DAC/preamp. So, in price terms, it sits in the middle ground, along with the likes of the Bryston BDA-1. But where does it stand in terms of performance?

The Naim DAC's biggest claim to fame is that it promises to deliver zero jitter through its S/PDIF inputs. Let us, however, just clarify that for the sake of any pedants: Naim says that the DAC adds no jitter to the signal coming through those inputs.

Any jitter that was present in the original production of the music – and there is nearly always some – will still be there so Naim cannot truthfully describe the DAC as zero jitter. No DAC can deliver that!

This zero-added-jitter is achieved by passing the incoming signal to, what Naim describes as a rotating data RAM buffer, independent of its timing information.

The signal data is subsequently read out of the buffer having been re-clocked by one of ten ultra-low noise, fixed frequency oscillators selected to match best the average incoming clock frequency and then send it through a SHARC DSP digital filter, running Naim-written code, which oversamples – or up-samples – the data (16-times on a 44.1khz sampled signal.)

This ensures that the signal entering the dual mono, 24-bit, Burr-Brown PCM1704K DAC chips – as used in Naim's top-of-the-range CD555 CD player – is completely isolated from any incoming S/PDIF jitter.

As usual with any Naim design, great – some might say obsessive – attention has been focused on the power supply arrangements and upon keeping mechanical interference at bay. At several points in the design these considerations meet.

The main power supply capacitors, for example, are removed to their own separate circuit board because they can vibrate when charging up – a mechanical disturbance can cause problems if it reaches other components.

We tested the DAC within the context of a Naim system, but it is important to note that it can just as easily be used in any other manufacturer's set-ups. Make sure, however, that you feed it with the best sources, if you want to exploit its full potential. for example, we used it with an iPod Touch and the performance was exceptionally good for an iPod.

That said, making a purse out of a sow's ear is beyond any DAC we have yet encountered, the Naim included. And that's not being rude about the iPod, the performance of which was very credible, but nonetheless wanting in comparison to genuine high-end sources.

We found it simply lacked the dynamic edge required to elevate it above the status of hotel lobby music.

The Naim DAC comes with eight S/PDIF inputs through BNC, RCA and TOSlink connections, has two USB ports and can process hi-resolution audio data files up to 32-bit/768khz (although these will need to be on top-notch USB sticks). The S/PDIF inputs are all isolating and work up to 24-bit/192khz.

The DAC is also, naturally, power-supply upgradeable. To augment the integral supply of the DAC, we took advantage of this by using the XPS that formerly powered the analogue stages of an HDX hard-disk player.

This provides a worthwhile lift to its already dramatically impressive performance, and is well worth doing if you find yourself with an otherwise redundant XPS... or you have £2,850 burning a hole in your pocket with which to buy one.

Sound quality

All of Naim's fanatical attention to detail pays dividends here: that much is obvious from the moment the DAC starts doing its job. Its performance is clearly in another league to anything we've heard before.

Music emerges with startling clarity and amazing levels of detail, while timing is absolutely on the button. In fact, you had better prepare yourself for a real surprise if you do not associate stereo niceties with Naim, because the DAC does sound-staging, timbre, spaciousness and all that high-end audiophile stuff as well.