I've been using Winamp 5 and sometimes EAC/PsyTel to encode my CDs to AAC format.

First, does anyone know what compressor Winamp 5 uses? I've heard bad things about FAAC, so hopefully it doesn't use that.

Now I tried compressing my wav files to "AAC" using Quicktime Pro, as I've heard thats the best. I get .mp4 files in return... But these can't be played in Winamp, and even if I change the extension to .aac, Winamp won't play them.

What exactly is the difference between my .aac files and the .mp4 files? I've heard if you rename the .mp4 files to .m4a files, you can play them on your iPod. What about .aac files, will they play on your iPod?

My iPod is supposed to be here in like 4 days, so I'd like to know before I rip the rest of my collection to .aac =| If .aac won't work, I'll just go for mp3s, because I want to be able to play my music in Winamp as well as on my iPod.

Thanks,
~ Tim