MusicCheck is more than a normal midi controller, with our unique Prisma Composer you can systematically create or modify a melody in a 3-step process: 1. Specify chords allowed in your melody. 2. Choose a rhythmic pattern for your melody. 3. Finally select groups of notes you want to vary. MusicCheck runs through all possibilities, for example with 10 chords and 6 groups there are a million different possibilities!!!!!! We use a flexible prism coloured graph representation of all the different possibilities. You can further configure the possible variations by restricting groups to certain chords. Save and load Midi projects and extract the different chords with the Prisma-Composer or connect your Midi Keyboard and record new songs. With a simulated turntable you can control the playback of your songs or play them backwards. This mobile Midi-studio is able to load SF2 and DLS SoundFonts or you can start right away with some built-in instruments.