a companion app for the Roland JX-3P and PG-200 A companion app for the
Roland JX-3P and PG-200 not affiliated with Roland Corporation* contact

Hello JX-3People.

I’ve owned the JX-3P since it was released. I bought it at Down Home Guitar in Anchorage, Alaska, as a freshman in high school. I own many synths, but have kept and played the JX-3P since that time.

I’ve always wanted a way to easily save patches to my computer. But the JX relies on outdated tape dump technology — think, the hiss, chirp and screech of an ‘80s dial-up modem + audio cassette tape as memory! I couldn’t find a program so I decided to build my own. This was also an excuse to figure out how to “vibe code” — something I knew nothing about until I began in May of 2026.

JP Patches for Mac JP Patches for PC

Fast forward a month and I have JP Patches, my JX-3P companion app. It works on macOS 12+ (w/ an Apple Silicon chip) and Windows 10 and above. It doesn’t yet support MIDI — the stock JX-3P MIDI does not support SysEx. I’ll wire up support for the Series Circuits MIDI Upgrade Kit in a future release. JP Patches operates through tape dumps using a single cord.

JP Patches main panel — PG-200 style knobs and switches on the right, active C/D patch list on the left, Tape Memory controls below

WHAT CAN JP PATCHES DO?

Record-from-JX-3P modal mid-capture — JP Patches receives the tape dump audio with a live level meter and segmented transmission timeline Send-to-JX-3P modal — JP Patches plays the tape dump out to the synth with timeline progress and pulse indicator Custom Bank Builder open below the panel — 4×8 grid filled with patches dragged in from multiple library packages, origin labels on each slot Library tab showing the sequence editor — piano-roll visualizer with edits in progress, save-as-new-copy flow

HOW DOES IT WORK?

USB-to-1/4-splitter cable connecting a MacBook to the JX-3P's Tape Memory Save and Load jacks

  • use this USB-to-1/4-splitter cable
    (or your audio interface)
  • plug the TS end into Tape Memory/Save
  • plug the TRS end into Tape Memory/Load
  • plug the USB-C end into your computer
  • alternatively, you can upload WAV files

JP Patches for Mac JP Patches for PC

FISHING FOR FEEDBACK

Friends have successfully loaded JP Patches, but none are synth people so they just say, “looks cool dude — congrats!” If you are a JX-3P enthusiast, I’d invite your feedback.

I’ve been using JP Patches for the past few weeks. It works fantastic—but it’s just me using it. I send C/D banks back-and-forth between my computer and JX. I send sequences. I edit sequences within the app, save ‘em, and send back to my JX. I create custom names for my personal JX C/D banks. I turn knobs on the PG-200 onscreen because it’s fun (it’ll be more fun when MIDI is working). I went ahead and seeded JP Patches with my personal patches and a sequence I wrote so a new user of the software will see something upon initial download. In the future I envision JX users easily trading patch banks, sequences, and enjoying the JX-3P with the modern conveniences of software.

You’re either a JX-3P owner or terribly bored if you’ve read this far. I’ve never written software, let alone software for a 1983 relic that has somehow held my attention all these years. If it’s not obvious at this point, this is personal passion project (3P!). — Daniel Spils