AAC when well encoded sounds great, but there are too many sub-par encoder implementations that just don't sound good - sometimes worse than MP3.
If you're encoding AAC use either Apples encoder, or one of those from Fraunhofer:- Fhg-AAC available as a paid plug-in, or free with WinAMP, or the Open Source FDKAAC implementation originally for Android, but now available cross platform.
> …there are too many sub-par encoder implementations that just don't sound good - sometimes worse than MP3.
Whoa, I'd never imagined that could be the case and appreciate the heads-up. I've only had experience with the Apple and Fraunhofer encoders so far.
Mind calling out the offender(s)? This summer I'm releasing a best practices guide (and hopefully tools) to help podcasters move to AAC, and that would be useful to mention.
The FFMpeg wiki has some information, including calling out its own "vorbis" encoder as sub-par and not recommended (but apparently they also support a different "libvorbis" encoder that does not suffer from problems?) See https://trac.ffmpeg.org/wiki/Encode/HighQualityAudio
If you're encoding AAC use either Apples encoder, or one of those from Fraunhofer:- Fhg-AAC available as a paid plug-in, or free with WinAMP, or the Open Source FDKAAC implementation originally for Android, but now available cross platform.