Here are some instructions for setting up a
Raspberry Pi 3B
or a
Raspberry Pi 4B
as a MIDI host for USB or Bluetooth musical equipment.
The purpose is to build an as-simple-as-possible device with no user interface that can be switched on and off
by simply connecting/disconnecting to/from a power source.
This is being used daily since months by hundreds of musicians and by me on the following equipment: