Modifiying a Roland M-16C to M-64C and transferring the factory sounds

A couple of months ago I scored three M-16C on German eBay. My intention was to do the famous M-16C to M-64C conversion, since an M-64C costs more than the three M-16C together. Plus it’s good soldering practice.

When I got the JX-10, it had no factory sounds – the internal memory was all messed up. To solve this two things are required:

  1. A Roland M-64C cartridge. The JX-10 can only take full dumps, and those can only be done to a cartridge. Once on the cartridge however, they can be copied to the internal memory.
  2. The firmware upgrade from Colin Fraser. Here’s a post how I replaced mine.

Installing the new firmware is the easiest part. The harder part is to modify an M-16C. So if you choose the easier and more expensive path, just buy an M-64C.

Modification

I’ve found two guides the original one and another one based on the original one. The original guide has a nice description, but very low-res photos. The other one has good pictures but a not much text.

The first thing to do is to desolder the old memory chip from the M-16C and for me this was the hardest part. It took about an hour and I used a solder sucker.

Another thing was to actually understand where to solder each lead. Some are easy to see, some are not. One that shouldn’t be missed is the one that you have to solder beneath the chip before soldering the chip.  Here’s a photo from one of the guides, it’s the red lead. It’s connected to the second pin in this photo, very hard to spot, but if you look carefully it’s visible between the blue ones.

You also have to bend a few pins upwards, this is quite clear in the text in the original guide,  in the other guide you can see it in this photo.

The final thing to do is to modify the casing, one of the guides recommends a Dremel, for me a filet knife did the job.

Transfering 

There are some instructions scattered all over the internet,  sosummarized it here:

  1. Download banks and CpJX
  2. Insert an M-64C cartridge
  3. Set the Protect Switch on the JX-10  to OFF
  4. Set the Protect Switch on the M-64C cartridge to OFF
  5. MIDI Channel should be set to 1. [MIDI PARAMETER 12]
  6. SYSTEM EXCLUSIVE needs to be ON. [MIDI PARAMETER 14]
  7. Connect both MIDI IN and MIDI OUT
  8. Launch CpJX and configure the right MIDI ports
  9. Load a sysex file and choose Transmit
  10. Go to the JX-10 and push the MIDI button then push the WRITE button. The display responds with: “WRITE MIDI”
  11. Rotate the Alpha-Dial until the display responds with: “MIDI BULK LOAD”
  12. Push the ENTER button
  13. The JX-10 now should handshake with CpJX and the transfer should start. Takes about a minute, and both the JX-10 and CpJX should alert you when the transfer is done.

Primary source: SUPER JX-10 and MKS-70 SYNTHESIZER HOMEPAGE