Oversampling rate in J River

One thing to understand is that the USB interface, and in particular, the master clocks, is the MOST IMPORTANT thing in a USB digital computer audio system. More important than the DAC itself. More important than the sample-rate that you are playing back.

To prove this to you here are some anecdotes:

http://www.avguide.com/review/musical-fidelity-m1-dac-and-v-link-usb-adapter-tas-213

Latest issue of TAS, Steven Stones review of the iDAC

Steve N.
Empirical Audio

Steve,

I wonder if you've seen anything about the SOtM tX-USB and SOtM In-Line SATA Power Noise Filters out of South Korea. Chris of Computer Audiophile recently built a new audio server with these two components and they seem to address a lot of what's plaguing consumer-grade PC audio systems. The USB card in particular uses it's own molex power, uses a capacitor bank for filtering and then implements their own 3.3V and 5V rectification. It also includes a switch to turn the power off and only send data (I know some DACs require power); this is pretty revolutionary stuff for us PC audio freaks.

The best thing about it, the is an entirely seperate USB bus (because it's acutally a PCI bus) and won't be shared by other devices.

This coupled with a HiFace or Off-Ramp would take a system to the next level...

Sorry to get OT, Steve just mentioned something that sparked my memory.

" One thing to understand is that the USB interface, and in particular, the master clocks, is the MOST IMPORTANT thing in a USB digital computer audio system"

I believe that proper word instead of "master clocks" would be the "real life jitter". The master clock's jitter shows the potential, however, when you build your server or DAC (or buy elsewhere) number of factors will degrade its actual performance and it depends solely on the builder to isolate and "annihilate" them. Its not "off-shelf" stuff.

Also, I must mention output stage... for generations, most modifiers here made their living on upgarding output stages and every one with ears know the improvments of "better" output stage.

Of course what we are talking about here is jitter and all of the contributors to jitter. I have written several white-papers on this:

http://www.positive-feedback.com/Issue43/jitter.htm

http://www.positive-feedback.com/Issue22/nugent.htm

http://www.positive-feedback.com/Issue14/spdif.htm

The point I'm making is that if the master clock is not REALLY GOOD, all other bets are off. It does not matter how careful you are downstream. The damage is already done. And this damage makes all of the fancy technology that you put into the DAC worthless.

Steve N.
Empirical Audio