Best bitrate for AAC

[PuzZLeR]

I hear that a good "compromise" bitrate for mp3 is 128kbps. It has a "good enough" CD quality sound with little loss to the human ear. So they say, and I agree.

What would be the equivalent for AAC?

Here's my real question: If you were to convert MP3 audio at 128kbps to AAC, what bitrate should you use to get relatively "equivalent" quality? I heard that you can encode AAC at 64kbps (half) and get away with it since its compression is much better. Does anyone agree, or disagree with this?

And if anyone can comment on an equivalent argument for AC3 to AAC as well, I'd appreciate it. Thanks in advance!

[The1]

If you are happy with mp3 at 128kbps, you will be happy with AAC at 64kbps no question about that.

Just did a quick test converting mp3 128kbps to AAC LC 64kbp/44100 Hz stereo using Easy CD-DA Extractor and player both back on Foobar 2000 you will not be able to tell the difference in quality.

As for AC3 to AAC there are numerous posts on this, just type AC3 to AAC in the search box above and start reading!