I've been through mp3Gain help and forums a bit, and it seems interesting for what I'm doing at wiki-babel.org. I record users' voice directly online, and currently use sox to normalise volume. Which doesn't really have the effect I was hoping for, but I think MP3Gain will solve that, although I might have to tweak it to work on ogg/vorbis format instead of mp3. Is that even possible?

My real question is this one though: is it possible to use MP3Gain to evaluate a perceived recording quality? What I mean is something similar to call quality for VoIP. Is the voice clearly heard? is it easily understandable? I suspect this is not the right app to do so, but I assume there are a few sound processing nerds here who might be able to point me the right way. Any tips?

thanks for your time!