Boss' SY-1000 is a synth orchestra you control with a guitar
 

There's more than one way to turn a guitar into a synthesizer. But Boss and Roland have always gone for the most elaborate and complicated approach. While the new SY-1000 can be played simply by plugging in a guitar or bass via a standard 1/4-inch in...

https://www.engadget.com/2019/12/05/...effects-pedal/