Viewing Issue Advanced Details
ID Category [?] Severity [?] Reproducibility Date Submitted Last Update
08183 Sound Major Always Jan 17, 2022, 03:01 Sep 29, 2022, 19:16
Tester kmg View Status Public Platform MAME (Self-compiled)
Assigned To kmg Resolution Fixed OS MacOS X
Status [?] Resolved Driver
Version 0.239 Fixed in Version 0.240 Build 64-bit
Fixed in Git Commit 412098b Github Pull Request # #9167
Summary MESS-specific 08183: nespal [gimmick]: DPCM audio plays at wrong pitch
Description The bass line in the title screen music (and other tracks) is done by playing samples on the NES's DPCM channel. It is noticeably out of tune (about a half-step flat?) with the melody and implied harmony. Is this an APU bug that affects all PAL games? Presumably it is correct on hardware. Other emulators have correct pitch.
Steps To Reproduce mame nespal gimmick

or alternately

mame famicom gimmickj to hear the music in tune (also has additional sound channels)
Additional Information
Github Commit
Regression Version
Affected Sets / Systems nespal [gimmick]
Attached Files
There are no relationship linked to this issue.
User avatar
Senior Tester
Jan 17, 2022, 07:28
edited on: Jan 17, 2022, 08:39
Alright, it looks like this is due to not having an appropriate table to generate the correct frequencies for the DPCM channel on PAL—it just reuses the NTSC table. With a correct table I think the PAL version of Mr. Gimmick should have music at approximately the same pitch as the NTSC version. In other words it should sound very close to running "mame famicom gimmickj" and then turning the volume off on that game's extra AY clone chip.
User avatar
Senior Tester
Jan 17, 2022, 10:05
There are probably other examples, but it turns out Sunsoft really likes this bass line via DPCM samples idea. Besides "gimmick", sets "batmanrj", "gremlin2", "silius", "sspyhunt", and "ufouria" are all PAL versions and all sound horrible due to the bass part being flat on the nespal driver.
User avatar
Senior Tester
Jan 22, 2022, 21:28
I've added the commit this was fixed in. I believe this can be closed unless someone knows a reason otherwise.