prophet-rev4-mods

The arpeggiator has Up, Down, Up/Down, Random and Assign modes over 1 to 4 octaves, HOLD latch, 40 to 300 BPM by knob or tap tempo, MIDI clock sync and thirteen note values including triplets and swing. The sequencer records up to 512 steps of chords (10 notes each, with velocity), rests and ties from the keyboard or MIDI, plays forward, backward or pendulum, transposes from a key, and can feed the arpeggiator as a chord progression. Arp settings are saved with each program, and a Recorded user program also stores its sequence in an unused area of the synth's flash. Holding A440 at power-on bypasses the patch. The project builds on an arpeggiator mod that circulated privately and keeps its control layout (A440 as the arp button). Verified on a Prophet-10 Rev4; the Prophet-5 Rev4 is untested on hardware.

Download Sequential's Main OS 2.1.0 (prophet5_main_2.1.0.syx), drop it on the browser patcher, which checks the input and output against known hashes, and send the patched file over USB as SysEx like an official update (Globals, MIDI SysEx = USB). Send the original 2.1.0 file to go back to stock. Recovery from a failed update is through Sequential's documented bootloader procedure.