Tag Archives: digital audio

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Air gaps

The long-awaited PS Audio music server, Octave, is inching closer to making its debut in late 2019. Since I’ve not written much about it recently, I thought you’d enjoy an update about one of its innovations, a new invention called the Air Gap Audio Interface or AGAI.

The AGAI solves a big problem in digital audio servers, contamination by noise and electrical detritus.

Inside a server, you have a noisy computer. As it chugs away at its tasks it jitters and pollutes the output signal feeding the DAC. This is why, we believe, FLAC sounds differently than WAV even though the bits are identical. A FLAC file (for example) requires far more bit crunching to extract the original bits than does a WAV file. Those crunched bits contaminate the final output signal through mutually shared power, ground and physical signal traces.

How can we fix that?

Imagine that the noisy computer inside the server was not in the server box and was instead far away (as we are doing in the upcoming Ted Smith Signature DAC). Its noise and ground contamination would not be a problem as long as we took its distant output and regenerated it in a Digital Lens.

Since our goal is to build a one-box server, the next best thing is to physically isolate the two systems within a single chassis. To do that we need separate power supplies, ground planes, physical boards, and at the end of the proverbial day, a physically isolated connection between the internal computer and the output Digital Lens. That’s where the AGAI comes into play. By bridging the gap between the internal noisy computer and Digital Lens by nothing more than light traveling through air, we get excellent isolation.

(In the upcoming TSS DAC the problem is solved with two chassis: a digital and analog separated too by light using a fiber optic cable between the two.)

We’re all familiar with digital data transmitted through lightwaves using a TOSLINK cable but that won’t work for either of our applications because of TOSLINK’s bandwidth limitations. But that isn’t a show stopper. It just means we have to step up our use of technology. Some of the highest speed data in the world travel on beams of light.

Whichever method is used, AGAI or high-speed fiber, transmission of digital data over lightwaves offers the possibility of getting noise and jitter out of the signal and gets us that much closer to musical perfection.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Drop ins

I am often asked for a recommendation on a piece of digital audio equipment that a person could simply drop in and hear how it is better than vinyl. A simple, easy, demonstration of one format’s superiority over another.

Unfortunately, I don’t know how to do that. Sure, we can all agree on digital’s technical superiority in terms of noise, dynamics, frequency response, transient attack, distortion, etc. Yet, replacing one piece into an analog ecosystem won’t demonstrate anything other than how alien it is.

Think of it as making as much sense as dropping a piece of modern furniture into a living room decorated in a completely different style. You’re unlikely to get a good feel of how that single piece would play out in a surrounding more acclimated to its style.

When we set up a system we’re doing so in a way that honors and accentuates the virtues of one format at the expense of another.

In the same way that plopping in the world’s best turntable into my digital optimized kit won’t tell us much of anything—other than it’s out of place—dropping a state of the art DAC into an all analog setup is doomed to failure too.

I wish I had an easy solution to help people experience the benefits of one vs. the other, but alas, drop-ins just don’t work.

They are about as welcome as uninvited guests at the family Thanksgiving dinner.