Set GLB-8 [MIDI] → Clock Source to EXTERNAL, then send MIDI Clock from the source into the Prophecy's MIDI IN. If the arpeggio still does not start, check its keyboard scan zone.
Do this first
- Connect the clock source's MIDI OUT to the Prophecy's MIDI IN.
- On the Prophecy, open GLB-8 [MIDI] and set Clock Source to EXTERNAL.
- Start the external clock source and play a key inside the selected arpeggio keyboard scan zone.
Diagnose it
Is the Prophecy set to EXTERNAL clock?
Yes: Check that the source is actually sending MIDI Clock to MIDI IN.
No: Set Clock Source to EXTERNAL in GLB-8 [MIDI].
Does a held key fall inside the arpeggio keyboard scan zone?
Yes: Check the external clock output and physical MIDI cable.
No: Adjust the pattern's keyboard scan zone to include the played key.
Expected result
The arpeggiator follows the received MIDI Clock tempo.
Why this works
Korg defines EXTERNAL as the mode in which incoming MIDI Clock controls the arpeggiator. Its troubleshooting table also points to Clock Source and keyboard scan when an arpeggio does not start.
Still stuck?
Recheck the physical MIDI direction and the exact source device setting. If this behavior differs on your hardware, keep the model/revision and setup details for a correction report.
All Prophecy fixesSources & review
Last desk review: . Documentation does not replace a physical hardware test.
- Prophecy Parameter Guide · Korg
Sections reviewed: GLB-8, p. 139; Troubleshooting, p. 175.