The three most popular audio transcoders for Windows, OS X and Linux respectively are CDex, Max and SoundConverter. All three are freely available for download and are open source as of June 2015.
All three support reading and writing in multiple formats including MP3, Ogg Vorbis, FLAC, ACC, WAV, and Apple Lossless. Users can easily rip tracks from CDs to any supported format while album information is automatically retrieved and written to the output file. Individuals can extensively alter the encoder settings, including audio quality, by choosing between static or variable bit rates and channel settings. Advanced features such as normalization, file metadata editing and error correction are available.