I have a CD that I use for listening for high frequency quality and ambient echo which may be useful for tuning LAME. Off the Cirque du Soliel "O" CD there are numerous high quality tracks that can be used but one in perticular is track 1 (Jeux d'eau) where high quality string plucks, bells, and cymbals are lightly struck and have after-resonance and ambience that is unmistakable. With --preset standard on v3.96 the ambience sounds more dry and the resonance of midrange frequencies is clearly lower in volume (or missing) that are audibly present in --preset extreme. Quick successsive low-volume strikes on cymbals in this track in the left channel during certain moments clearly aren't perfect on any of the presets.

Yes, I ABXed too and the things I mentioned here are hard to miss IMO. Extreme and Insane sound the same to me (in quality) on this track. Maybe I could upload the whole track to someone and then you guys can pick out the best examples based on your own expert ABX'ing skills. I just don't know where to send the wav file.

mp3