squid4 wrote:Super Street Fighter II graphic glitches are gone with fpgagen-20181109.rbf but the music and sound still has issues and is very quiet with this game.
I have tried the different Street Fighter II games:
- Street Fighter II Special Champion Edition: volume is low, but music and SFX are correct
- Street Fighter II Plus: volume is low, but music and SFX are correct
- Street Fighter II The New Challengers: volume is very low, SSG seems louder than it should
I do not hear anything that seems obviously wrong in my version (JT12 v0.52). SSG might be a bit louder than it should -which is something we can fix- and FM volume is set very low in these games -but that is software dependent.
YM2612 is a stripped down version of the OPN Yamaha core:
- least significant bits of sound thrown away
- limited internal dynamic range means that volume must be attenuated by software -as documented by Yamaha-
So overall, unless the sound engineer paid attention to this properly, when porting music from other Yamaha chips the result can be a quieter song. I can imagine two patterns:
- Games whose music was programmed using an YM2203 equipped Japanese computer (FM towns, PC88 or similar)
- Games that are ported from arcade, where an YM2151 was used
In both these cases, volume parameters needed special attention when porting the music to YM2612. And I think that -probably for schedule reasons- this detail was often overlooked.
In summary, I don't think there is much we can do. We could add a volume control on the OSD for very quiet games, but core developers rejected this option before because this would be the only core with that option. So I think you are left to your desk top amplifier.