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View Full Version : Lame alt-presets compared to Vorbis


cjv
10th December 2002, 05:15
I hope this does not seem like a "what's better" thread, because it's not intended to be. It's purely out of curiosity (as I now prefer Vorbis regardless)
I've searched here and at HA, but I'm coming up with nothing.

The question:
1) I encode a 448kbps AC3 movie track to MP3 using lame 3.90.2 --alt-preset standard.
2) The resulting bitrate was 148kbps.
3) Now I encode that same AC3 track to Vorbis using the approx. quality for that bitrate, lets say -q5
4) Both filesizes are relatively the same (which is to be expected)
5) Now, I HAVE done these tests, and they do sound very close, but my hearing is not the greatest :)

I am very curious, from a purely technical standpoint, which file _should_ be more transparent? I know that Vorbis blows MP3 away at bitrates of 96kbps-128kbps. On the other hand, Lame has been tuned very well for alt-preset standard, (but mainly for music I assume)
Vorbis is not yet tuned for higher bitrates, but is the technology still so much better than MP3 that it stands a
better chance?
I'm curious what other people think?

cjv

The tests in case anyone is interested:
1) Downmix 448kbps AC3 to stereo-WAV file, using standard BeSweet switches
BeSweet.exe -core( -input "C:\Audio-448.ac3" -output "C:\Audio-448.WAV" -2ch -logfilea "C:\BeSweet.log" ) -azid( -n1 -c normal -g 10db -L -3db )
2) Encode WAV->MP3 using lame --alt-preset standard, no other switches
Resulting Average bitrate: 148kbps
3) Encode WAV->OggVorbis -q5

JReiginsei
10th December 2002, 06:17
This post may answer your question

http://www.hydrogenaudio.org/index.php?act=ST&f=9&t=2729

Vorbis is better IMO because it has less overhead when using the .ogm container, better syncronization, and also LAME is tuned for 44.1 kHz while I believe vorbis is tuned at 48 kHz as well.