I studied Ogg Vorbis posts hard and it is still unclear for me:
1. What quality setting do I have to use to get encodings not worse than with LAME 3.90.3 APS? (I think q6, am I right?)
2. What is the difference in stereo encoding between q5.99 and q6.00?
3. Is it safe to use q6.13 or q5.24? Or they can produce worse quality than q6 and q5?
4. Is Ogg Vorbis better than LAME 3.90.3 APS in classical music in most cases?

P.S. All questions are about GT3b1.

IMO, q5 is transparent to -aps
q6 gives almost the same filesize as -aps

all gt3b1

That is subjective and depends on the person's ears. So you'll get different responses from different people.



q 6 is when lossless stereo coupling occurs. Essentially Vorbis saves bits by transmitting the differences between channels. It usually works well until we hit the low bitrates where we get 'stereo collapse', and it sounds rather mono. At q 6, there is no 'loss' there. Unless your hearing is very sensitive to stereo separation, I doubt you will hear much difference between 5.99 and 6.00.



AFAIK, fractional qualities are very safe to use.



If I remember, guruboolez pointed out some problems with Ogg Vorbis on classical music. Since GT3b1 is based on Vorbis 1.0, these will remain unfixed. However, I suspect they only affect low bitrates. So at the quality values that GT3b1 is typically used (>= 5), the artifacts will be different. People have reported that Vorbis suffers from a high frequency boost on all q values. Some find this annoying, some find this negligible, and some find it makes it sound better than the original.

I've used q5, 6, & 7 for classical without any problems. My ears are quite sensitive so I have not tried any of the lower settings. As I've learned here, start with q5 and work your way up or down from there.

As far as hich one is better, there is NO answer for that question. It's really an issue that's been beaten to death.

Thank you all for replies.
So why didn't one implemented this in LAME. Let me guess - MP3 doesn't support it?

I'm not that familiar with joint stereo coding in LAME but I do seem to recall that in the FhG mp3 encoder, that they recommended joint stereo at bit rates below 192 kbps and just normal stereo at 192 kbps and above.

LAME uses joint stereo on all of the alt-presets AFAIK. fhg is not a good reference because its joint stereo is buggy. Since LAME doesn't do Intensity Stereo that only leaves full Stereo which is less then ideal most of the time. I think even the lower bitrate settings use js.

I also think the case is buggy implementation of Joint Stereo of FHG codec. And that's why I did answered the question about Ogg Vorbis stereo lossless coupling.