How to directly control your OP-1 with a midi keyboard via a Raspberry Pi - YouTube
5 Tips & Tricks for the Teenage Engineering OP-1 - from UK distributor Sound Technology Ltd
Any way to hook up a MIDI keyboard that only has Micro USB to the OP-1 as a controller without a DAW : r/OP1users
oplab - teenage engineering
USB MIDI Host for an OP-1 which connects USB MIDI controllers to it (NOT like a Kenton which is more expensive and connects only 5pin DIN ones) : r/OP1users
Anyone invented a midi usb host cable yet? - OP-1 - OP Forums
Teenage Engineering's OP-1 Field is a big refresh with a big price tag | Engadget