I’d like (to buy or make) an expression pedal to speed up/slow down the tempo while playing. For example a song may start out at say 120, but then during the bridge speed up just a little to say 121 or 122, then go back to 120 for the next verse. It would be cool to program the tempo change in the song, and have it sweep during the transition, but even better would be a foot pedal to speed up or down.
I’d think this could possible via MIDI? I’m a hacker/maker, so I could program an Arduino to send MIDI messages, based on an analog pot foot pedal. Is there a list of available MIDI commands?
Or maybe add a couple options to the footswitch menu, say left to decrement BPM, and right to increment it.