In the topic http://www.hydrogenaudio.org/forums/index....showtopic=58933, I've touched some of the issues below, but I'd like to concentrate in the title's lossy formats...

1. For stereo-only music (no 5.1ch, no movie), which are the best encoders for ac3 and mp2?
2. Which settings should I use in each encoder in order to achive general transparency?
3. Regarding quality/size, is there any advantage on using one format over another?
4. Does any one know which encoder Audio DVD Creator uses in ac3 encoding? They've not replied me yet...

Thanks for any help.

Rosivaldo.

Wow! No reply so far. Are my questions too silly? :-)

Rosivaldo.

I guess it shows how many people are using the Audio DVD Creator.

I highly doubt that it has the Dolby encoder for AC-3, it is most likely the same library available in, for example, ffmpeg and ac3acm.

So forget DVD Audio Creator. Its ac3 output reduces the sound volume too much. I need a stand-alone ac3 encoder. May someone help me with the other (first 3) issues?

Thanks again,

Rosivaldo.

I don't know about "best", but in my experience two good encoders are Aften (ac3) and tooLame (mp2).


Not sure about ac3. For MP2, I think 256 - 320 kbps can provide transparency in most cases.


AFAIK, open source AC3 encoders do not provide great quality, so I would stay with MP2.


Sorry, I don't know.

Regards,
Irakli

As for mp2, I once tried QDesign MPEG Audio Codec 1.01 for ACM which came out quite well on a www.soundexpert.info 224 kbps listening test. I preferred it a bit over twolame or toolame (I don't remember which one of these I tested). Struggling for transparency 320 kbps were needed for the problematic tracks I tested in either case.

BTW, What is the difference between twolame and toolame. Are both part of the same project?

QDesign is somewhat expensive to me... :-(
Do you mean that you have achieved transparency at 320kbps using QDesign *and* (too/two)Lame? I didn't get it well...

Rosivaldo.

Qdesign was transparent to me at 320 kbps, though tw/olame was very good as well.
I installed Qdesign from a codec bundle it was contained in. Thought it was free (hope it was - but I don't use it any more anyway).

I don't know about the differences between twolame and toolame.

"Very good" means that, although good, two/tooLame was almost, but not totally, transparent to you even at 320kbps?

Rosivaldo the curious. :-)

I found my little Test.
As you can see it was not exactly about transparency. Moreover mp2eenc was the alternative to QDesign mp2.
A note on transparency: As you can see from this test transparency is a very relative thing, even for one person. And the most important thing: it's relevant for only rare samples. Using 320 kbps simply should be fine, and I wouldn't worry much about few samples that might not be transparant especially as long as you take the judgement from somebody else. Taking care of specific samples should at least require having listened to them on your own IMO to get a feeling about what's not totally ideal to somebody else.
Other than that you have the option to go 384 kbps with mp2.