Inspektor Gadjet Arduino USB MIDI Host - Usb Midi to Serial converter.
Cheap DIY MIDI To USB Adapter | Hackaday
midi-usb-interface · GitHub Topics · GitHub
Amazon.com: NUOSIYA MIDI Cable, MIDI to USB Interface Cable 4.5FT,MIDI Interface in-Out to USB Cord Adapter with Indicator for Piano Keyboard to PC Mac Laptop,Arranger Keyboard Tool : Musical Instruments
Mini USB-MIDI to MIDI – Simple DIY Electronic Music Projects
Arduino MIDI Interfaces – Simple DIY Electronic Music Projects