It's not a sonata in the "well known" multi-part form, but in it's bare, original meaning. As it is completely improvised and formulates multiple different musical ideas in one piece, I'd like to call this kind of piece an "Impronata".
For those who own a 7.1 surround system, an 8-channel FLAC file can be picked up here to get an impression of what it will sound like in my living room:
- URL: http://via.woody-mc.de/to/t-8ezBbeFeK3_kvK
- Player: Current versions of Media Player Classic are able to properly play multi-channel FLAC files.