The Prophet64 is a discontinued hardware cartridge for the Commodore 64. It features four applications, supports SYNC24 and lacks MIDI support.
The Prophet64 is replaced with the fully MIDI compatible
MSSIAH Cartridge
Prophet64 - Getting Started
Prophet64 - Sequencer
Prophet64 - Mono Synthesizer
Prophet64 - Bassline
Prophet64 - Drummer
Prophet64 - Free Trial Versions