February 2010

Tools of the Computer Trade: Part Two

In last month’s editorial, I talked about why I feel that the future of audiophile-based music systems will involve not a physical disc format like CD or SACD, but music files stored on computers and played using high-quality digital-to-analog converters (DACs). If you’ve been following what’s been going on in audio the last few years, this is hardly an earth-shattering prediction. Sales of CDs have been on the wane for a decade; the newer digital formats of SACD and DVD-Audio never grabbed market share; and for years now, many people have been assembling systems just like the one I’ve described, not only to improve the quality and convenience of CD-resolution playback, but to take advantage of the higher-rez formats available today. The question most relevant to readers now is, If I don’t already have this kind of system, how do I create one?

This article describes my own foray into computer-based digital audio. I’ll tell you what I’m currently using here in my reference room, including the pros and cons of such a system. It might give you some idea of how to build your own such system, now or in the future.

Although there are other companies out there, digital photography is ruled by Canon and Nikon. They’re biggies, and their products are what most consumers shop for. Unfortunately, their systems aren’t compatible; when you get into digital photography, you go with one brand or the other. Each has its pros and cons, its admirers and detractors.

Computers are pretty much the same. You have Apple Macs, and then you have all the Windows-based PCs. Our editor-in-chief, Jeff Fritz, has gone the Apple route, using a MacBook laptop. I’m on the other side of the fence, with a Sony Vaio laptop running Windows Vista. As with digital cameras, you’ll hear arguments from both sides for which computer system is better. But such disputes can’t really be resolved; each system has its pros and its cons. You just pick one and stick with it.

Many people have reported problems with Vista, but I’ve never had one. On the other hand, I wish that the soundcard built into my laptop, which is now just over three years old, supported resolutions higher than 24-bit/96kHz. I don’t want to replace this computer just now, but if I were buying a new laptop today, I’d make sure its card supported 24/192, to take me a little bit further into the future -- music is now available in that resolution, and more will be coming our way.

Besides the operating system and soundcard, you need a software-based music player. There are a number of Windows-compatible players, but I settled on foobar2000, which is available online for free and permits bit-perfect transfers of high-resolution material when you add on what’s called "kernel streaming." Then you’ll need something to play. Sometimes I download files; other times I rip CDs using Exact Audio Copy -- which, like foobar2000, is free.

Before I mention the other components in my system, I have to clarify one thing: I could use the DAC on my computer’s internal soundcard and just connect the analog outputs to my preamplifier’s inputs. But the sound quality of this cheap card doesn’t satisfy me, and I haven’t come across one that has. That’s why I feel I need a high-quality external DAC.

There are a number of ways to get the digital signal out of your computer and into a DAC: two of the more popular connections are FireWire and USB. FireWire is a good connection and is common on Apple Macs and Sony PCs (mine has it). I suspect that’s not for its audio but its video capabilities, which Apple and Sony are both big into. Some DACs support that interface, notably Weiss, but USB is the standard to which most audio companies now design their DACs.

One of the very best USB-type DACs now on the market is the QB-9, from Ayre Acoustics of Boulder, Colorado. It’s designed from the ground up to be the best USB DAC Ayre could build for a reasonable price ($2500 USD). They’ve succeeded. The QB-9 works flawlessly and sounds fantastic, supporting resolutions up to 24/96, and is upgradeable to play 24/192 when that becomes available. If you want to know all the details -- there are plenty -- read Peter Roth’s excellent review of the QB-9 on our sister site, Ultra Audio.

If you’re committed to high-end computer-based audio right now, the QB-9 is the DAC to get for its ability to deliver very high performance at a price that, for an audiophile-grade component, is still reasonable. But before you get out your credit card, know that one of the QB-9’s great strengths is also its only limitation. The QB-9 is equipped with a USB input that, to minimize jitter, operates asynchronously. The weakness is that this USB input is the only digital input the QB-9 has -- you can’t attach the QB-9 to a CD transport that has a traditional S/PDIF digital output. To play CDs through the QB-9, you’ll have to first rip them to your computer, or play the discs using the computer’s built-in drive.

But spend some time with the QB-9 hooked up to your computer and it won’t take you long to discover why computer-based digital audio is growing. I downloaded Ola Gjeilo’s Stone Rose (2L 2L48SACD), which I wrote about last December, as a series of 24/96 FLAC files. (The album was originally recorded at 24/96, so these downloads have allowed me to hear the recording at its "native" sampling rate -- no insignificant thing.) I compared the sound of that download to the CD edition, using the best CD player I have on hand: Simaudio’s Moon Evolution SuperNova. The SuperNova sounded great, as always, but the higher-resolution FLAC files through the QB-9 sounded better yet -- a fuller re-creation of space, more presence to the piano, and better decay from Gjeilo’s keystrokes. Plain ol’ CD, no matter how good the player, sounded dated by comparison.

But not everyone has $2500 to spend on a DAC that accepts only USB. If you still want to spin CDs easily and would rather get your feet wet with something very inexpensive that still sounds good, there’s a fine option for you: NAD’s C 565BEE CD player ($799), which has a TosLink digital input that’s claimed to handle PCM datastreams up to 24/192. I reviewed the NAD C 565BEE last December, and was so smitten with it as a CD player that I bought the review sample and promised myself that I’d experiment with it as a hi-rez DAC. Now I have.

Because the C 565BEE doesn’t have a hi-rez USB input (its front-mounted USB jack supports only MP3 and WMA files, which are both lower than CD resolution), you’ll need a device to convert USB to TosLink -- which is exactly what Blue Circle Audio’s new USB Tunnel 24/96 was created for. The USB Tunnel 24/96 (from $399, depending on configuration) will convert a USB signal from your computer into RCA- or BNC-based S/PDIF, XLR-based AES/EBU, or what the C 565BEE needs: TosLink. And, true to its name, the USB Tunnel 24/96 will pass datastreams up to 24-bit/96kHz.

The USB Tunnel 24/96 is an ugly little thing, but it’s simple to set up and proved flawless in use. Since the Blue Circle is powered straight from a USB port, the only wires are the USB cable that links it to the computer, and the TosLink cable from the Blue Circle to my NAD C 565BEE. Once connected, my computer recognized the Blue Circle as a valid USB device, the NAD locked to it, and in no time flat music came through -- beautifully. I compared the Stone Rose CD (played in the NAD) to the 24/96 FLAC download and heard the same striking improvements I’d heard when I compared the QB-9 to the Simaudio SuperNova: superior space, decay, and presence. In fact, I liked the sound of these hi-rez files played through the USB Tunnel 24/96 and C 565BEE better than the CD through the SuperNova, which costs over $6000. That’s the way it is when you have higher-resolution source material, I guess -- as the resolution increases, you can have better sound for a fraction of the price.

The Blue Circle USB Tunnel 24/96 with NAD C 565BEE did fall short of the Ayre QB-9 by a little bit. The QB-9’s extraordinary resolution is perfectly complemented by a nonfatiguing sound that I can listen to forever. The combo of Blue Circle and NAD approached but didn’t beat it, so there’s still reason to pay more. But even though the Blue Circle and NAD didn’t match the QB-9 straight from my computer, it did get close, and for less than half the price -- which to me, given its quality and versatility, makes the combo a no-brainer purchase. (Remember, the C 565BEE plays CDs, too.) What’s more, the NAD is equipped for 24/192 input. When I can send that resolution from my computer, I’ll be interested to hear the results. Stay tuned . . .

I’m an audio reviewer, and thus privy to the best equipment there is, but what I use in my own system can be had for a very reasonable price. After all, most readers are less interested in pie-in-the-sky stuff than in equipment they can actually afford. Whether you use a USB DAC like the Ayre QB-9, a combination like the Blue Circle Audio USB Tunnel 24/96 and NAD C 565BEE, or something else, getting into computer-based audio should be a priority if you want to sample the future of digital playback right now. It’s certainly changed the way I listen to my system, and there’s a good chance it can change yours as well.

. . . Doug Schneider