InfraRecorder - available under GPL license and can be used to convert MP3 music to audio (cda) format in Microsoft Windows.
To convert mp3 to audio (cda) format, all you need to do is to select InfraRecorder » choose Audio Disc » drag the MP3 file to file list » Click Burn the current compilation to disc
Using InfraRecorder, you can also compile a CD/DVD, record disc images (ISO, BIN, CUE), record dual layer DVD's, fixate discs and many such features.
You can check InfraRecorder at
http://infrarecorder.org