RolandSynths
1993 synthesizer module from Roland's JD-800 line
The JD-990 is a synthesizer module released by Roland in 1993, related to the JD-800. It plays up to 24 voices, each patch layering up to four tones. In performance mode it runs seven parts on separate MIDI channels with shared effects. Patch memory is battery-backed RAM, and the module is editable over MIDI System Exclusive.
No custom firmware is known; the entries here are host-side editors that work over MIDI SysEx and leave the module's own software untouched.
Open-source macOS editor and librarian for the JD-990. Edits all patch parameters live over MIDI SysEx, with draggable envelopes, a performance mode view and a searchable patch library.
by André Motz
| Version | Date | Notes |
|---|---|---|
| main @ 08f0ce2 | 2026-10-10 | No tagged releases; this is the latest commit. |
