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He's done it again! Fred was talking about this for quite some time but a few months ago, his talk became reality. Fred Vecoven's new digital PWM kit for the Roland Super-JX is just amazing. Simple, elegant and delivering great PWM for this much loved classic, this is a must have for every JX-10 or MKS-70 owner.

Fred Vecoven's Digital PWM Kit - daughter-boards
Much smaller than the original PWM daughter-boards and a whole lot easier to install.

Anyone familiar with installing Fred's original PWM upgrade, will be aware of just how involved it was. Without my V02 mounting bracket, the daughter-boards  needed to be secured to the Super-JX's voice-boards which meant drilling holes! 🙁 Then there's the wiring... and there's a lot of it.

As its predecessor, the new digital PWM kit for the Roland Super-JX, still requires the changing of the 8031 processors on the Super-JX's voice-boards but the new daughter-boards only need to be fitted to the holes left after removing the 82C54s counters (IC19 - IC22) . Although straight-forward, it's still a very time consuming task.

Roland Super-JX voice-board being prep'd for Vecoven digital PWM daughter-boards
In addition to removing the 8031 (IC10, top left), the four 82C54 ICs also have to come off each voice-board.

The daughter-boards generate square and PWM waveforms and as a side benefit, they consume less power than the original 82C54 counters, which isn't a bad thing.

As mentioned, installing Fred's new PWM kit for the Roland Super-JX is much more straight-forward than the original version. The simplicity of the installation also means that the likelihood of error is also greatly reduced . Extreme care however, needs to be taken when removing all those ICs!

My supply and installation service for the new PWM kit is therefore much cheaper than what I was charging for the original kit.

Fred is full of surprises and indeed things seem to be continually happening around the Roland JX-10 and MKS-70 and in the Super-JX community. To make fault diagnostics easier if anything ever goes wrong, is another reason why I put sockets in-place of the counters, thereby allowing Fred's digital PWM daughter-boards, to be snapped in and out (if necessary), from the voice-boards.

Socketed digital PWM for Super-JX
Socketing Fred's latest PWM upgrade makes installation a bit longer but future proofs your Super-JX and means that the daughter-boards can be easily removed, if ever necessary.
Digital PWM installed on Super-JX Voice-Board
Simple and elegant, Fred Vecoven's new digital PWM upgrade for the Roland Super-JX is quite simply beautiful.
Digital PWM daughter-board for MKS-70 In Situ
And here's the re-assembled MKS-70, showing a digital PWM daughter-board installed on the top voice-board.

Here's a link to Fred's page: