Written for a Novation LaunchControl as a stand-alone controller
• Uses buttons to play sustained (drone) notes with variable velocity
• the patch sends data back to the LXCL to light on-notes according to the velocity set to give visual feedback

Might work with other controllers that respond to note events being sent back (AKAI? LaunchPad? If so, please add here or https://community.blokas.io/t/midi-controllers-with-led-buttons/4015/2)