This is really easy to do. To assign a preset to a specific MIDI channel, simply cursor up to the top left hand corner of the main display to where "C" is displayed. This selects the MIDI channel you want the unit to respond to. As you rotate the data knob, this will change from C01A through C16B. Select the MIDI channel you want the particular preset assigned to, then use the CURSOR buttons to move the cursor to the bottom row. This is where you select the preset you want to play. If you are using the Proteus 2000 to play one sound at a time from a keyboard you have connected to it, place the Proteus 2000 in Omni Mode (Master, MIDI Mode, choose Omni), or simply set the keyboard and Proteus 2000 MIDI channels so that they match. Then cursor down to the second line to select the preset you want to play.