Passive Quad Midi TRS Converter

AB:BA is a passive 4‑way MIDI TRS‑A to TRS‑B (and vice versa) converter that swaps tip and ring on each TRS jack so devices with different TRS MIDI standards can communicate, like TRS‑B (Arturia/Novation/Flame) with TRS‑A (Korg/Elektron/Squarp).