If ever there were a sign that the wind has changed direction, its when an established brand with a reputation for building excellent – if slightly conservative – products decides to jump on the latest trend in the business. Maybe I have the wrong impression of Audio Research, but I was quite surprised when it delivered a DAC that is also a streamer. The Reference DAC Digital Media Bridge (to give it its full title) is capable of playing almost all the digital formats in current use (except DSD), whether it be supplied by a CD transport, a computer or a NAS drive. It also has a volume control. It’s a frenzy of features by high-end standards and one wonders whether it can do so many jobs as competently as the three separates it represents.
But this is a reference level component that has the same vacuum tube output stage and power supply as the Reference 5 SE line-stage preamplifier. It is built on the sonic qualities of the Audio Research DAC8 and incorporates technology from the Reference Anniversary preamplifier. It would seem that it’s paperwork is very much in order as far as existing technology is concerned, so what does it bring to the picture in terms of more up to date requirements?
The answer is plenty. It has wired and wireless Ethernet access, it offers the V Tuner internet radio service, which covers pretty much everything out there, and has connections for S/PDIF cables of electrical and optical persuasions, AES/EBU is naturally onboard as well. There are USB connections for portable devices and for high speed computer connection plus another for USB sticks on the front panel. The Reference DAC has a 3.5inch TFT display and both front panel and IR remote control switches to navigate around it. Any product that streams from a server needs something like this if you are going to be able to find the music you want to play, in truth it really needs an app for your iPhone or iPad, and at the time of reviewing this was still in the pipeline. Fortunately generic control apps like PlugPlayer will work too. The panel also shows you which of soft or sharp filter options have been selected and whether upsampling is engaged. It can perform positive integer upsampling up to 192kHz – in other words a 44.1kHz CD sample rate will only be upsampled to a maximum of 176.4kHz to avoid complex processing which tends to muck up sound quality. The actual converter itself is capable of processing signals up to 24-bits/192kHz.
The analogue side of the equation is provided by a zero feedback triode output stage consisting of four 6H30 tubes with a 6550 and 6H30 in the power supply. It also has a volume control, but this fact is not mentioned in the literature and there is a suggestion in the manual that best results will be achieved with a dedicated preamplifier. It says to set the Reference DAC’s output level to 60 in this situation.
Cut to the chase, the Reference DAC produced some of the most refined sounds I’ve encountered in all my years in the business. I started out using the coaxial output of a Naim UnitiServe, a source that allowed the DAC to deliver masses of detail in an effortless and melodic fashion. It is an uncannily relaxed converter and those looking for maximum dynamic
impact may find it doesn’t have quite enough leading edge definition for their tastes, however it doesn’t take long before you are drawn into the music and start to enjoy the richness
of detail that’s on offer. It’s by no means lacking in dynamics either, it’s just that there’s no digital grain or undue emphasis, it’s devoid of that type of distortion, presumably because of that class A output stage. But there’s more to it than that. Put on acoustic material and everything sounds right, there’s just the right amount of space and a very natural sense of pace along with very convincing tonal rendering.
It images extremely well, there’s a solidity to instruments and voices that places them firmly in the room, with the acoustic of the original recording all around them. You don’t even have to play pure acoustic music to appreciate this, the kick drum on a track by Frank Zappa is reproduced realistically and with the full depth of the instrument in front of it.