Hi everyone,
Only the other day I chanced upon your site and found out a lot of new and useful things! Thanks a lot. This night I spent encoding and comparing audio-cd to different formats . I desided to use laac to encode audio-cd. So, the question is - what options do you use? As I could understand, 16k bandwidth is used by default. Is it really enough? I tried to enlarge it to 22k using option "-c22000", but frankly didn't notice any difference at all. What do you say?

I hope you are aware of the fact that FAAC is supposed to be "not mature and tuned yet".
If you want to play around with mp4/AAC a little, get the Nero 5.5.10.35 demo with mp4 encoder (50 encodes trial), and use the VBR presets with high quality
I did a few quick checks for the lowpass thing in Cool Edit, nero VBR normal::high seems to have a first "regular" lowpass at 18KHz, a second very strong one at 20 Khz and some very few freqs even go up to full CD audio spectrum. Looks very nice

EDIT: before I get bashed, spectral graphs say not much about audible quality. BladeEnc also encodes full spectrum at 128k mp3 I mentioned it because you asked, I guess..