Is computer audio a bust?

10-21-14: Audioengr
"Barry Diament (recording engineer of some renown) did blinded comparisons of master files in either AIFF or WAV, and there was no discernible difference"

So what? Steve Nugent did the same comparison and found a significant difference.

This is entirely system and track dependent. Recording studios are notorious for compression and using inferior playback systems for their mixing.

Steve N.
Empirical Audio

Barry is an audiophile/engineer so that does not necessarily apply to him. His current hi rez recordings are some of the best I have heard. I myself go back and forth on this issue. I think AIFF is better than Apple lossless, and depending on my mood, I also think WAV is a little better than AIFF.

If you analyze people's opinions on SQ superiority of WAV versus AIFF or any other format, its a coin toss statistically. What does that tell us?

The next time you have a dinner party, do a blinded test for your guests and see what you get. I trust non-audiophile ears more....

0-21-14: Ptss
Agear I did not intend to be confrontational or flip. I had considered your question as serious

I assumed that but wanted to make sure...

I am hopeful the best is yet to come from computer audio

I feel the same. Sky is the limit, but much of it is embryonic.

Again I ask "would adding an original Alpha Dac make a worthwhile improvement to an Oppo 105D?" (And what would be the ideal interface?)

There's only one way to find out. I assume it would. I heard an Exemplar Audio modded Oppo and it was very good. John Tucker, like Steve at Empirical, does very good work and is an actual engineer.

One question I have for Mr. Nugent is why are current dacs overwhelmed by incoming jitter. Overcoming jitter is their raison d'etre. Is this an engineering shortcoming that we even need Overdrives, etc?

Thanks Steve.

What does that tell us? Its obvious to me based on 15 years of listening to systems at trade shows and in salons. Most systems are not resolving enough or low noise and distortion enough to make these differences obvious. I have heard a number of reviewers systems as well. Same thing, unfortunately. Most systems simply have a preamp that creates so much masking and compression that these differences cannot possibly be heard. Good active preamps are like hens teeth.

Steve N.
Empirical Audio

Current DACs have difficulty reducing jitter to inaudible levels because this is a difficult engineering challenge, even for seasoned designers. It always has been. The jitter on S/PDIF inputs on DACs is generally reduced somewhat by the receive chip, which uses a PLL to recover the clock from the datastream, but a low jitter input to this receiver chip is still beneficial. Other DAC designs use resampling chips and circuits to establish a new master clock. These can reduce jitter even more than the receiver chip, but there are two downsides: 1) they inpart their own kind of distortion due to way that the resampling algorithm is implemented 2) the new master clock and associated circuitry/power supply adds its own jitter.

Thes best solution for reducing jitter in a DAC is to put a master clock front-end on the DAC. There are two types of these available now, the Async USB interface and the network renderer. Both of these effectively discard the clock in the source computer or device and generate a NEW master clock.
if the power, circuit design and clock selection is optimized, the jitter can be extremely low with these input circuits.

The thing to understand is that these are not easy to design and its really esy for lots of jitter to creep back into the circuit, even if you u a Femtoclock etc..

also, jitter is never reduced to zero as some manufacturers would have you believe.

Jitter when characterized by a single number, such as RMS jitter is an inadequate measurement. Jitter has a spectral component as well as a distribution of amplitude. these are actually more important than any single number to predict if one jitter is more audible than another.

Steve N.
Empirical Audio