It seems everyone is making – and talking about – digital-to-analogue converters, but we’ve been here before, says Andrew Everard

Open any hi-fi magazine, or click on any Internet forum where audio is discussed, and you could be forgiven for thinking that DACs – digital-to-analogue converters – have come to save the world. Just about every manufacturer has at least one in its range, and many new names, from companies best-known for computer accessories to all-but-unknown Chines manufacturer and what seem almost like garden shed operations, making products in small numbers and selling direct online.

You can pick up a DAC for as little as £30, or you can spend many thousands of pounds on a converter, and they come in full-size hi-fi casework, in little USB ‘dongles’ or even built into cables. You can buy DACs with USB inputs as well as the usual electrical and optical S/PDIF hook-ups, DACs doubling as headphone amplifiers, pocket-sized units designed to be carried in your pocket with your iPod or iPhone, docks with DACs and even one packing an atomic clock against which digital data is referenced.

That last one is the Rubicon Atomic AD/DA Preamp, made by Antelope Audio – you may remember I covered it in my report from the German High End 2012 show earlier this year – and it will set you back around $40,000.

What’s more, there’s a whole cottage industry springing up around DACs, with the same people keen to tell you that ‘digits is digits’ or ‘it’s all about 1s and 0s – simply get that right and the sound will be as good as it can be’ willing to enthuse about what can be improved by changing the power supply on a budget DAC, or even self-building or buying battery power-packs for their chosen device.

Unfortunately, casual buyers swept up in this whole ‘DAC to the future’ frenzy seem confused: read those online discussions and you see questions like ‘Is it possible to buy a CD player with a DAC built-in?’, ‘Can I put a DAC between my Blu-ray player and AV receiver to improve the sound of surround soundtracks?’ and ‘How do I add a DAC to my mini-system to make it sound better?’.

The answers to those questions, by the way, are ‘Yes, they all have one built-in, but only a few let you plug in external digital components’; ‘No, because the DAC can’t decode the surround sound formats’; and a simple ‘No, because there’s nothing for the DAC to add to such as system’.

What goes around...
We’ve been here before: when I first started writing about audio, DACs where everywhere, following the launch in the late 1980s of Arcam’s Black Box, which finally made use of the mysterious ‘digital out’ sockets on the CD players of the time. When I bought my first player, the manual hinted that the socket was there to allow features such as pictures on CDs to be shown on a connected TV – whatever happened to that one? – but what the likes of the Arcam did was allow early players with limited digital-to-analogue conversion resolution to be updated to the then-current specification.

Yes, we’ve been here before, which is why DACs had their time in a audio limelight, then gradually became a less important part of the market.

A quarter of a century of refining the design of CD players, and the level of performance available from even modestly-priced machines is more than a match for the exotica of the early days of compact disc, which is why I’m not surprised to read things like ‘I bought a DAC to improve the sound of my CD player, but having tried it for a few days, I’ve taken it back for a refund – compared to my player, it sounded very poor.’

It just goes to show that yes, a separate DAC has its uses – but, just as two decades ago, it’s neither a universal panacea nor a must-have. However, there are now more DACs on the market than ever before, and that’s for a very good reason: if your music is stored on a home computer or portable device, the addition of an external converter can form a high-quality bridge between it and your audio system.

Some computers offer an optical digital output – on laptops it’s sometimes hidden in the headphone socket – and so can be connected directly to an AV receiver, which has built-in digital to analogue conversion; others even offer an HDMI output, allowing audio and video to be transferred.

All computers, however, have USB connectivity, and that’s where the modern DACs come in: most have a USB input for this kind of connection – though you should check the one you buy has a Type B USB input for a computer, and not just a Type A to which the likes of memory devices and portable players can be commected.

So yes, DACs have an obvious use or two in the modern music landscape – but before you buy, make sure you really need one, and get an audition to ensure you’re getting an improvement, not just an extra box.