Fraunhofer l3enc was the first public software able to encode PCM files to the MP3 format. The first public version was released in July 1994. This commandline tool was shareware and limited to 112 kbit/s. It was available for MS DOS, Linux, Solaris, SunOS, NeXTstep and IRIX. A licence that allowed full use (encoding up to 320 kbit/s) cost 350 Deutsche Mark (about $250).
Since the release (9 September 1995) of Fraunhofer WinPlay3, the first realtime MP3 software player, people were able to store and play back MP3 files on PCs. For full playback quality (stereo) one would have needed to meet the minimum requirements of a 486DX2/66 processor.
By the end of 1997 l3enc stopped being developed in favour of the development of MP3enc, which is the successor to l3enc. It was often refered to as the "MP3 encoder with the best quality". It was available for MS Windows, Linux, Solaris, SunOS, IRIX and Alpha. Development of MP3enc stopped in late 1998 to favour development of a parallel branch FhG had been developing for some time, called Fastenc. All of these programs are no longer actively marketed. An mp3 Surround encoder and mp3HD Codec / mp3HD Software Tools are now promoted on the Fraunhofer MP3 website.