WAV vs. FLAC vs. AIFF

DTC, thanks for the good response, with which I am in essential agreement.

I would just like to make sure it is clear to everyone that under my hypothesis cpu utilization which is low but non-zero may actually be WORSE with respect to noise generation than, for instance, 100% utilization would be. The noise transients I am envisioning are associated with the abrupt SWITCHING of cpu clock rate, and in some cases voltage as well, that unless disabled by the user will occur as processing tasks intermittently start and stop.

That switching involves LARGE changes in cpu current draw, which happen quickly, although I don't know exactly how quickly. Current changes that are both large and fast = large noise transients.

For those who may be interested, utilities such as the Windows-based program CPU-Z allow those changes in clock rate and voltage to be observed as they happen. It should be kept in mind that cpu current draw is highly dependent on clock rate.

Happy Thanksgiving to you and yours!

Best regards,
-- Al

"The amount of processing used to decode a FLAC file is really minimal. I just do not see that minor extra processing having much effect."

I'd say that is a true statement plus the fact that on a general purpose computer for example, there are many processes and threads executing at any particular time, so it is hard for me to tie any adverse effects in general to just that process. Yet another reason to isolate system from general purpose computer as best as possible as an insurance policy at a minimum.

""Malfunction"? Are you saying that the 16/24 bit data for each sample is incorrect? That the data that comes out of a flac decode is different that the wav data?"

Yes, I believe its incorrect when the decoding is done on-the-fly.

Steve N.

"The idea that the FLAC decoder produces wrong numbers is just not credible. People have repeatedly shown that the compression/decompression algorithms works."

Yes they have, but only staticly, never real-time.

Electrical noise in the PC is not the cause of these differences, and jitter is not the cause either. Noise will not change significantly with different tracks or different formats. Jitter is a non-issue with Async USB.

Steve N.
Empirical Audio

EDorr - are you using a USB interface? What player S/W? Are you using a Preamp? What ripper did you use?

All of these must be optimized in order to get stellar results, and to hear these differencees easily.

Steve N.
Empirical Audio