what do you think of these lame options for ac3->mp3 audio encoding?

[ixpi2001]

-vbr --resample 48 -V1 -q 1 -b 96 -B 320 -m s

why these options:
-vbr with min 96kbit and max 320 lets lame chosse the appropriate bitrate
-m s makes a 2channel-mp3 for the surround info to be preserved


the interesting thing about these options is:
-with 448kbit-ac3´s as source lame chooses 96kbit to be the best bitrate, for the whole file.
- without resample lame would change the sample rate to 32khz, anyway, with 48khz file size is the same.

so, what do you think- is lame so good it can preserve the ac3 quality with just 96kbit or is something wrong about that options?

[pacohaas]

please read the audio FAQ for recommended LAME settings. (hydrogenaudio link)

For the most part the --alt-preset's work the best in all modes, so check those out and see which best suits your needs. LAME has a good joint stereo mode, so specifying stereo instead will decrease the quality of your output.

try something like --alt-preset standard or one of the ABR presets if that is more to your liking.

[ixpi2001]

thank you, isnt alt preset using vbr too? if not i dont see the point using it, as cbr and abr are just inferior to vbr..
vbr, which lets lame choose the bitrate as it is needed/best to encode, makes lame encode the whole file with 96kbit - that means to me, just use 96kbit, preserve 48khz and you got 1)best achievable quality at 2)minimal filesize.
joint stereo isnt a bad idea of course

[pacohaas]

Originally posted by pacohaas
please read the audio FAQ for recommended LAME settings. (hydrogenaudio link)

...
try something like --alt-preset standardlet us know how that turns out.

[ixpi2001]

aha! lame alt-preset help brings a bit of light. ok, from my ac3 track it produces a 32kbit up to 200kbit mp3. interesting! the -vbr at quality 1 doesnt change bitrate at all and the preset changes it all the time- that seems a bit weird to me, as one could mean the possible difference between the two settings has to be marginal...
so long, thank you, that way i found an even better setting!

[pacohaas]

yeah, i think there might have been some problems with -V1 in older LAME versions, it's recommended to use the latest versions (non-alpha) for best encoding quality.

the vbr presets shouldn't resample your audio to 32khz, in fact, the --alt-preset standard won't resample unless you specify --resample. so maybe you're using an incorrect command-line? are you using BeSweet with lame to go directly from ac3 to mp3? if so, post your logfile or somethin and maybe we can figure it out.

[ixpi2001]

no, i was misleading perhaps. everythings fine. i was just wondering why vbr produces a constant bitrate mp3 and alt-preset is extremly varying its bitrate, but as you said it might be the v 1 setting.