The sf3 format, developed by MuseScore, is similar in all respects to the sf2 format except that the samples are stored in the OGG format (like the MP3 format but open source) instead of being stored as raw data. The consequence is that the sf3 format is about 10 times lighter than the sf2 format for a comparable quality.

A soundfont exported in this format is not intended to be edited later because successive compressions would result in a lower sound quality. This format should be seen as a final product and is very interesting for all end users of soundfonts in that:

Unlike the sf2pack format which answers the same issues, the sf3 format is entirely open-source. The source code is available, thus ensuring its perenity (let's avoid the mistakes done with sfArk or sfPack!).