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RDX opens .syx voice cartridges from classic 6-operator FM synthesizers, plays every voice through a built-in FM engine, and lets you rename, reorder, merge and export new banks — all on your device.
6-op FM engine.syx 32/64 voicesMIDI + keyboard0 tracking
Features
Preview, instantly
Play any voice through a faithful 6-operator FM engine — on-screen keys, computer keys or MIDI in.
Rename & reorder
Edit voice names inline and drag to organize your bank exactly how you want it.
Merge & build
Cherry-pick voices across many cartridges and export a fresh bank.
32 or 64 voices
Export single 32-voice cartridges or 64-voice (two-bank) files — split with no loss.
Pitch & mod wheels
Expressive preview with bend and modulation wheels, plus full MIDI device selection.
No accounts, no cloud
Your files never leave the device. Nothing is uploaded, ever.
See it in action
Demo video coming soon.
Screens