opl synth

[Lemonzest]

Hi

been playing doom2 in dosbox which has sound blaster sb16 opl synth emulation, and decided to try zdooms opl emulator and zdoom sounded nothing like dosbox playing vanilla, the sound had hardly any of the instruments and it sounded hollow.

could zdoom's be improved? i belive the synth was added sometime in 2002/3?

thanks

[randi]

It sounds fine to me. During the development of the OPL code, somebody even sent me MP3s recorded from a Doom session running under DOS with a real SoundBlaster 16 for me to compare against. There were a number of small errors in the MUS player library I had to fix until I was satisfied that it was as close to the original as possible.

The biggest thing that can contribute to it sounding wrong is if your opl_frequency is not exactly set to 49716. The MAME OPL core used by ZDoom (and DosBox) doesn't cope well when it has to resample.

[Csonicgo]

I have to agree with randy, and my own ears, it's pretty much the same thing. In fact, it's accurate as can be at the time. until we have DMX though, don't expect 100% simulation.

[Lemonzest]

Tracked it down, with MSVC builds the opl music sounds fine, gcc build sound off key and up a few pitches and is missing sounds :S maybe gcc is screwing something up?

ZDoom GCC

http://lemonzest.tastyspleen.net/zdoomgcc.mp3

ZDoom MSVC (RazTK Build)

http://lemonzest.tastyspleen.net/zdoommsvc.mp3

Edit:Glad I was not hearing things.

[randi]

A GCC debug build sounds fine, so it's probably mis-optimizing somewhere.

[Lemonzest]

how do i change that? i thought the only optermiserations were march=i686 -mcpu=pentuim and -O2

[randi]

I have isolated the specific optimizations that caused it to produce bad code, so the updated makefile now disables them for fmopl.cpp. You will need to delete releaseobj/fmopl.o to rebuild it without those optimizations.