Some extra details and a screenshot since someone asked. I’m happy to help folks out in return when I can:
I do have the JNX Rage for the proper button mappings now although I’m not using it for sound due to my self-made audio connector. The JNX Rage does support JAMMA-based mono or stereo if you have the original or a custom Primal Rage sound connector between the soundboard and main board, however. I just don’t know if that includes the subwoofer channel or not, TBH. I basically made my own direct sound output cable just to be safe as I definitely wanted the full sound mix (and it’s worth it; I introduced Primal Rage to a friend today including the massive thwomps when they land or fall on the ground LOL). Plus it was a good soldering learning experience and made me feel accomplished since those headphone jack wires are very tiny and bloody hard to solder 0.o
If your SuperGun has a stereo mini jack sound input, you could probably just do what I did. If not, there’s always ye olde RCA (red and white) audio cables which you can plug into a stereo or TV and chop off and strip the other ends for a custom connector, as well. I think all stereo cables are wired the same. Attached is a shot of the connector portion, where the red wire is connected to pin 1. On a side note, pin 1 is actually the left channel positive output, but my JST connector was just already pre-wired that way, otherwise I’d use a red wire to indicate the right channel if I were fully wiring it 100% myself just for posterity‘s sake.
Anyway, the line-level, non-amplified pinout on the Primal Rage soundboard from right to left (in the orientation of my picture attached) is:
1: L+ [left channel sound]
2: L- [left ch. ground]
3: R+ [right ch. sound]
4: R- [right ch. ground]
My JST connector is 6 pins, and I only needed the four connections above, so I cut off the other two unnecessary wires on it as you can see. One of them is over the “key” which is the pin-less spot on the soundboard output connector anyway (no pin, no connection), and pin 6 is actually the positive amplified left sound channel output for a tweeter in an arcade cabinet, so that one is basically going nowhere because of the other cut cord on the far left of my connector. I then took my cheap, spare stereo mini jack extension cord (6’ male little headphone jack style to female little headphone jack socket), chopped off the male end and stripped its wires, then I soldered the positive and negative JST wires (per the above pinout) matched up with the same polarity in the stereo cable. I’d show that too, but I covered the soldered wire connections with electrical tape to prevent shorts (if that’s even possible) and interference. You can use any stereo audio cable of your choosing—whichever is the most convenient for your HAS/home audio setup. There’s tutorials online that outline how to separate the positive and negative wires for each sound channel, but in short, it’s usually the copper wiring surrounding a red (for right) and white (left) separately shielded wire that are the grounds for each. You just have to unwind the surrounding copper wire and then twist it into it’s own “wire”, becoming the ground for that sound channel as hooked up to your JST. The articles online show this better (and pictures helped me out too).