Audiophile USB to PCM

When you say you "convert the VBR mp3," do you mean turn it back into a .wav? Hmm. If that is what you meant, one possible explanation may be that the CPU has to do more processing on an mp3 and that somehow causes audible changes--i.e., its "easier" for the computer to play back a .wav? Strange. But, it does take some serious time to create mp3s, so maybe...

Yes, I mean convert mp3 to wav. I can't imagine it has anything to do with processing power. If my ipod can do it at all then my 3.0ghz machine should be doing it effortlessly. One thing I haven't bothered to do is a .wav on the hdd versus the same track on cd.

This is a great conversation and I'd bet it has been read by many looking for the right solution for PC SPDIF out.

Ultraviolet/Rsbeck's gon posts about the M-Audio Audiophile (USB, firewire) have made me skeptical of the unit before it arrives on Wednesday. The PC digital out is the last piece in my system and has been the most difficult to choose. Here are the most important things I have gathered:

1. The M-Audio Audiophile USB using SPDIF digital to external DAC at least sounds different (and reportedly worse) than other units such as the Waveterminal U24. I haven't found any direct comparisons with RME or SoundDeluxe. All I've read about those are they are recommended. You can get a used RME card with SPDIF for about the same price as a USB Audiophile.

2. The piece matters! I'm going to re-post Dmitrydr's comment. If true, this seems to be the most important thing to know about buying SPDIF out for a PC: "you'll need a box (where jitter will inevitably appear) that accepts USB data flow, and converts it to SPDIF, i.e. performs quality reclocking, etc. Here, if this box is treated just as part of the audio system, and connected with short good SPDIF cable to the DAC, there should be less jitter then from a normal CD player. However, for low jitter this box must have audiophile-grade power supply, oscillator, and other parts, so its price level must be expected somewhere near any other audiophile DAC. Cheap solutions must introduce lots of jitter, making the whole idea nonsense."

3. The Waveterminal U24 is capable of not re-sampling 44.1 CD audio which may account for its truer sound (but no one seems to know for sure).

Oh, and Hbrandt -- you got me interested in this reclocking business with the Apogee Big Ben comments. Please convince me not to spend another $1k on it or I probably will ;-)

You can go from your computer to a Big Ben, You have to go from the computer to a converter that will convert USB to SPDiF. Edirol makes such a unit. Then take SPDiF from the Big Ben to the digital input in your DAC or Pre-Pro.

Computer -- USB -- USB/SPDiF Converter -- SPDiF -- Big Ben -- SPDiF -- DAC or Pre-Pro.

>>the apogee is a fine DAC, from all I've heard. But, I don't think it is in the same league as the Hbrandt's $14K dCS stack.<<

I don't mean to suggest that it is, but you can go directly from the computer to the Apogee Mini-Dac via USB, you don't need anything in between. The Apogee Mini-Dac has a Re-clocking solution based on the Big Ben. So, if you use the Apogee to re-clock rather than a Big Ben, you might be able to simplify a little and have less gear between your computer and DAC. I believe the Big Ben and Mini-Dac are similar in cost.

The question is -- if you go digital to the Mini-Dac or Big Ben and Digital out, do they both re-clock the signal --- or do they only reclock if they convert from digital to analog. I don't have the answer to that.