Ten years ago, I started a project to upgrade my loved JX10. This turns into a huge project where I ended up rewriting the complete firmware from scratch. Many people are enjoying their new JX10 or MKS70 with my firmware. Due to popular demand, I have ported most of the changes done on the JX10 to the JX8P. The little brother can now benefit from all these enhancements!

New features

In a nutshell, the rewrite provides :
New midi implementation
  • each parameter is now OFF/RECV/SEND/ON, allowing fine control of what gets sent and what is filtered.
  • sysex support : allow edition of tone parameters individually, including the "patch" parameters.
  • midi cc support : allow edition of all tone parameters with midi cc.
  • fast bulk dump/load : 1-2 seconds to dump everything. Can dump to/from cartridge and internal memory.
  • edition of parameters (patch and tones) sends sysex, so all editions can be sequenced. PG800 is also supported here, so editions made from the PG800 can also be sequenced.
  • copy from/to cartridge to create a full backup of the internal memory (all settings are now copied to the cartridge or restored from it)
  • flash module provides 32 internal banks (total of 32 x 32 tones = 1024 tones!). Preloaded with hundreds of tones.
  • M16C and M64C support : provide one or four extra banks of tones.
  • Import mode to load existing internet "dump" files directly into a bank.
  • any tone parameter can be assigned to the edit slider during play mode [coming soon !]
PG800 and mini-PG800 support
New display options
  • control whether updates from sysex, pg800 or controllers are displayed temporarily on-screen
Compatibility mode
  • allows to disable new features for full compatibility with old software (for example, sysex changes made to tone A can be redirected to the currently selected tone, etc...)
Chord mode


The new OS is available in flash module only (code is too big to fit in an eprom). The module provides 32 banks of tones and can be upgraded by sending a midi file. Eventual bugs (since the code is newer than the Super-JX one) are fixed as soon as being reported. New suggested features will be considered, contact me for more info!
The module is priced 99€ (+ shipping cost). It comes with a new eprom B. Installation is as simple as removing the old eprom and plugging the module. No soldering required. Please contact jx_sales@vecoven.com to order. Please download the manual for more information. When ordering, you will need to specify if your JX8P is an "A2" or "A3" version, see the manual for details.

Pasted Graphic

PWM kit

A new PWM kit is now available. It is described on this page.The install manual is in the download section.