But the main advantage will be more stable quality than SV7. Especially the little bit too much treble problem should be fixed in SV8. Editing/Fading of files without reencoding is possible. You can convert SV7 and MP2 to SV8. Streaming is possible (but not optimized for weak connections). 32 kHz and 48 kHz is possible. Up to 7 channels are possible. Increases dynamic range (102 dB => 256 dB). Tagging support. CDdb (not lke cddb or freedb, but more like imdb).
Besides, I noticed that with decreasing volume the bitrate of all 3 codes decreased too.
I think you're mainly testing the ATH curves/masking thresholds of each codec. This is something i thought about before, in conjunction with WaveGain prior to encoding, or older, relatively quiet recordings. I wonder if that could have a possible negative effect, because more of the signal goes down in the noise, or on the other hand, with overcompressed modern music, if more and more of the signal is left out due to temporal masking.
Vorbis (and I assume the others) have a 'floating' ATH curve. If you start out at 0dB then the codec will assume you can't be hearing the -90dB signal well, be it because it's too silent or because you blew your ears out with the 0dB signal.
tigre, I have a question: when you say, you compared the enodes to the original, after amplifying them back to normal volume, what original did you use? Imho it would be usefull to compare the processed original (WAV -> fadeout -> fadein) instead of the unprocessed source.
I remembered hearing something about MPC SV8 having support for a higher dynamic range than SV7.