I do remember now actually Bart said the core was good afterall as I recall he suspected it at one point.
I'm not going to be submitting anything to do with the gfx issues anyway, I just patched the memory so I can play it on the cab without it niggling me.
I think I've made a bit of progress with the sound though.
First of all I added the correct clock for the PCM chip which fixed the pitch but obviously the sequencer IC was still too slow. Looking at Thrill Drive which uses the same setup for sound, the irq was clearly being handled differently so I decided to port this over to the gticlub driver which helped but was still a bit out. Then I noticed Thrill Drive is a bit out too so the timer in k056800.c is possibly wrong.
I adjusted it a bit so it at least sounds right for now. The "slam" sample at the end of the thrill drive attract demo now triggers at the same time the title screen appears and the "gti club" announcer voice is in the right spot too.
Having checked out a few videos on youtube however on thrill drive it seems the k056800 envelopes for at least decay and release are also incorrect (by a long shot actually) so I suspect the attack envelope is also wrong. I've adjusted them a bit (to sensible levels anyway).
At this point I need proper recordings from PCBs though as I no longer have my GTI Club board so if anyone has a link to some good recordings it'd be a great help. Any of the konami boards which have the 056800 chip on the CPU board.
I think I can get these games sounding much better with the right source material
http://www.youtube.com/retrorepair
Edited by RetroRepair (01/27/13 11:48 AM)
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