Looking for a new stereophonic sound spectacular from your MP3s? Download the Fraunhofer IIS MP3 Surround player, MP3 Surround encoder and the MP3 Stereo eXtended converter. The no-cost eval apps, which are free of any watermarks, DRM or spyware, can be used to upgrade regular MP3 stereo files into MP3 Surround files. There’s an MP3 Surround streaming module too, for Internet radio stations to stream in surround sound at bit rates normally used for stereo MP3s.
Source : https://techcrunch.com/2007/01/18/fraunhofer-iis-mp3-surround-encoder-turns-your-stereo-tracks-to-51/