Yes, I'm very excited as my Nebula-X prototype PCBs have arrived! 😮
After developing Nebula balanced outputs for the MKS-70 in 2021, I received a lot of requests to do the same for the JX-10.
With considerably more issues to overcome and also wanting to address the noise picked up before the jack-board in the JX-10, I wanted to do more than just offer balanced outputs.
Like Nebula balanced outputs jack-board for the Roland MKS-70, Nebula-X is intended to provide balanced outputs for the Roland JX-10.
Since MIDI hardware resides on the jack-board and again, just like I did with Nebula, I've improved the MIDI circuitry using modern components.
Today my Nebula-X prototype PCBs have arrived so it's going to be a busy few weeks as I build this, make sure everything fits, test and confirm that the theory I'm implementing to combat JX-10 noise, actually works.
UPDATE - 8th June 2024
One big challenge with designing peripherals for vintage synthesisers, is the physical aspect of what you're doing. Designing electronics to work with older gear is one thing but making sure that what you have designed, actually fits, is another.
It's taken three attempts to end up with a Nebula-X PCB that actually fits. You measure, remeasure and measure again and you know damn well that despite having done this kind of thing many times before, it's going to take several attempts for the bloody thing to fit!
I made a slight departure with Nebula-X. Knowing that Nebula-X was going to be more expensive than Nebula MKS-70, I spent a long time researching components with a view to keep costs down. I didn't go for the original jack sockets, for example. Instead, I used a more readily available version. Still made by Jalco, they fitted perfectly. The programmer port was a similar story, as were the switches but I couldn't find a suitable substitute for the three-gang MIDI connector array. Luckily, that's still available.
As you can imagine, there were some compromises. Like Nebula for the MKS-70, the output level selector switch is replaced with a switch used to reconfigure Nebula -X to either deliver a stereo or individual outputs as this can't be done using the ingenious switching system that Roland employed back in 1986. The reason it can't be done, is because the switched versions of the 3-pole jack sockets that are needed to do that, are much wider than the 2-pole sockets and they simply wouldn't fit.
The other compromise is the programmer write protect switch. Unlike the original, Nebula-X uses a 2-position switch, simply due to the fact that I couldn't find a 3-position slide switch that fitted and matched up with the other switch. Things are much smaller now-a-days.
You'll also notice that the inside of the front of the jack sockets, have a metalised ring. The originals were all black but I think this will actually look pretty neat when it's finished.