Tech 21 ARMD MIDI Converter enables you to control the footswitch functions of Tech 21's Trademark Series of multi-channel guitar amplifiers and Landmark Series of Bass amplifiers with any MIDI controller. You simply connect a standard 5-pin MIDI cable from the MIDI out on your MIDI controller to the MIDI In of the ARMD. Then connect the 1/4" Out of the ARMD to the 1/4" footswitch jack on the amp you want to control with a standard instrument cable. An additional 1/4" Out is provided on the ARMD if you should want to control two of the same amplifiers. The ARMD is phantom powered through the instrument cable from the footswitch jack on the amplifier, so batteries are not required. A MIDI foot controller transmits information to remotely control anything that accepts MIDI program change information. In order to communicate program change information, the MIDI controller and the ARMD need to be set to the same channel. MIDI channels can be set on the ARMD by accessing six internal DIP switches via the removable back door.