For mono playback, connect a mono cable to the [OUTPUT MONO] jack. For stereo playback, connect a Y cable to the [OUTPUT STEREO/PHONES] jack and plug the other end of the cable into the L/R channel inputs of an audio system or two channels of a mixer assigned to left and right positions. To monitor the sound with headphones, plug the phones into the [OUTPUT STEREO/PHONES] jack. If you connect the optional foot switch FS01 to the [FOOT SW] jack, you can control start/stop and switch the sound of the MRT-3 with your foot. To synchronize the unit with a MIDI sequencer/recorder that has a MIDI clock output, connect a MIDI cable from the MIDI OUT connector of the device to the [MIDI IN] connector of the MRT-3.