Archived from ListenSmart.com, November 3, 2003. Historical; not current advice. Software, prices and links are as they were then.
Source: Wayback Machine capture.
UNIX & Linux Encoders
MP3Enc Windows/95/98/NT Shareware-$199 Homepage | Download
MP3Enc is the command-line back-end encoder from the Fraunhofer Institute. It converts AIFF, AIFF-C, WAV/RIFF and raw PCM data files into WAV or MP3s. Latest versions allow you to adjust bitrate, sampling rate, and encoder bandwidth/ quality. Additionally, with this encoder, stereo sound can be converted to mono when needed.
Please Note: This shareware version is recommended for the more advanced users only.