I recently got a Runark PCB and it came with the smaller version of the F2 mobo, wich turned out to be a bad choice for Runark as the PCB has a design flaw making the PSG sound very loud. In the soundsection they (Taito?) have tried to fix it by removing two caps, it's not enough the PSG is still loud but i guess it's better balanced with the FM/PCM than with the caps. I checked with M1 wich F2 games that use the PSG and it seems it's only Runark and Metal Black who does... at least much more than the other. I will switch Runark to the bigger F2 mobo and use the smaller for some other game, but i want to fix the soundsection first by putting the proper caps there. The sound differences is probably not big when having the caps there but i want it for completeness. I just don't know wich type and values they have. The caps are C8 and C7... see pic:
Hazarding a guess, I would say that it's likely to be C7=C9 and C8=C10 or they are the same as the other caps in that section.
No both caps has to be the same as it's for left and right channel... but still they are mixed to mono somewhere after those caps. I wonder if it's possible to get stereo sound from it? But i guess it's very likely the music is composed for mono only (same sound for both left and right with no stereo seperation). Hmm... those caps are possible the same used on the bigger mobo so i will have a closer look at it and use them if nothing else turn up
