Understanding the need for a smaller connections for MIDI-enabled devices, the MIDI Manufacturers Association has released specifications for the use of TRS connectors.
The specification is available to download and instructs how to wire tip-ring-sleeve connectors for use with MIDI devices.
We’ve all seen 2.5mm and 3.5mm TRS connectors used on multiple synth products over the past few years, instead of the traditional and somewhat bulky DIN connectors. The MMA wants to ensure that everyone is singing from the same hymn sheet, so that full compatibility between TRS and DIN-MIDI devices is assured.
Go to the MIDI Manufacturers Association website for more.