The Roland GR-30 normally receives in Mono mode, which uses six MIDI channels.
In order to accurately receive note information from a MIDI controller, the GR-30 should be set to Polyphonic Receive mode. Use the following procedure to
set the GR-30 to Polyphonic Reception Mode:
1. Power on while holding the [ + ] button.
NOTE: 'L_P' will momentarily appear in the display indicating Poly Reception Mode. Local control is automatically turned OFF. The GR-30 will remain in this
mode until the unit is turned off and back on again.