The problem, re things like the Mudcat CDs or other compilations, is that:
1. Many of the contributed audio files are from previously released commercial CDs, which naturally already have been "mixed" with reverb, digital delay, EQ, etc. No chance of an un-edirted audio file being submitted.

2. When we submit an mp3 or WAV or AIFF file for inclusion on the CD, we may wish SOME TRACKS of the audio to have more/less reverb, etc., than others To send in a 'pure' (un-tweaked) audio file does not allow for artistic decisions like this. (Maybe you want a little reverb on the voice but not on the accordion or banjo, or vice versa.)

3. While WAV files may be better quality than AIFF or mp3 as original file formats, I've been advised that if your original audio file was in, say, mp3, to convert it to WAV does NOT enhance the quality but, in fact, makes it WORSE.

4. Most important: I think that for a compilation album, if ANYTHING is changed from the original submitted audio files to the ones that are to be used on the compilation CD, the modified files need to be sent to the contributors first, for approval or modification.   

It does seem like we're learning how compression and other audio-homogenization techniques can strikingly alter the sound of an audio file, often for the worse.

The new Mudcat CDs are, indeed, gems and a tribute to the hard work and dedication and technical savvy of the people who put them together. Still, there are lessons to be learned from this, for future such endeavors.

Genie