YM3812

evildragon · Post by **evildragon** » Mon May 28, 2007 8:49 pm

So, how similar are YM3812's to YM2612's? They are both of the OPx-2 Series (ones an L, and ones an N).

I have successfully got my YM3812 to play some 2612 music, via converting them to a special 3812 format...

(using my old IBM Model 25 with an 8MHz NEC V30 CPU to play them)...

though, as you hear, sometimes a note gets stuck, or heck, it goes off key for some reason, and some notes seem to fail to even emit. oh yea, sometimes the temp gets all screwy, but that might be the NEC V30 not being good for music...

Streets of Rage 2:
http://blackevilweredragon.spymac.com/sor2.mp3

Sonic Green Hill Zone:
http://blackevilweredragon.spymac.com/green.mp3

Sonic Star Light Zone:
http://blackevilweredragon.spymac.com/star.mp3

Sonic Marble Zone:
http://blackevilweredragon.spymac.com/marb.mp3

Sonic 3 Balloon Park:
http://blackevilweredragon.spymac.com/balloon.mp3

Sonic 3 Boss (oh god this one played the worse, literally "forgetting" to change a note too many times):
http://blackevilweredragon.spymac.com/s3boss.mp3

So, how different are the two? it seems the 2612 can do better metallic sounds, and the 3812 can do more "toned" sounds.. not to mention, the 3812 isn't even stereo...

Shiru · Post by **Shiru** » Mon May 28, 2007 11:08 pm

OPL and OPN is a different FM synth chips series. They not directly compatible, and has different set of synth abilities.

Main difference: OPN always was 4-op with one osc. waveform (sine); OPL was 2-op (with 4-op modes) and selectable osc. waveforms.

evildragon · Post by **evildragon** » Tue May 29, 2007 1:27 am

Shiru wrote:OPL and OPN is a different FM synth chips series. They not directly compatible, and has different set of synth abilities.

Main difference: OPN always was 4-op with one osc. waveform (sine); OPL was 2-op (with 4-op modes) and selectable osc. waveforms.

then shouldn't that mean that i should be able to get accurate YM2612 emulation on a 3812? it has the 4 operator mode, and has the sine wave...

because it seems no matter how i try and run the YM3812, it just sounds weird.. (with the exception of Balloon Park being pretty damn close)

Shiru · Post by **Shiru** » Tue May 29, 2007 1:36 am

evildragon wrote: then shouldn't that mean that i should be able to get accurate YM2612 emulation on a 3812? it has the 4 operator mode, and has the sine wave...

I don't think it's possible to get accurace YM2612 emulation on YM3812, but, as far as I remember, very first emulators of platforms with Yamaha FM chips (SMD, some arcade games) used this idea to emulate YM2612.

evildragon · Post by **evildragon** » Tue May 29, 2007 1:45 am

but it should be possible to get better sound than what im getting with my 3812... mine is just pathetic, it's not even trying to get a metalic bass sound..

perhaps someone can make a DOS GYM player for YM3812's.. it would be awesome! (of course no PSG or DAC support.. i'd be happy to see FM support though)..

ohhh TmEE, think you can do that in QBasic?

all in real mode?

TmEE co.(TM) · Post by **TmEE co.(TM)** » Tue May 29, 2007 6:57 am

I think I can, but I'm pretty sure your V30 isn't enough to get decent speed unless I use some amount of ASM (but I'm not too good at x86 ASM)... I need to get some info on the GYM/VGM formats. DAC wouldn't be too hard to add (through LPT DAC, or SB DAC).

evildragon · Post by **evildragon** » Tue May 29, 2007 7:39 am

TmEE co.(TM) wrote:I think I can, but I'm pretty sure your V30 isn't enough to get decent speed unless I use some amount of ASM (but I'm not too good at x86 ASM)... I need to get some info on the GYM/VGM formats. DAC wouldn't be too hard to add (through LPT DAC, or SB DAC).

I think the V30 should be able to pull it off, I mean SEGA made the Z80 do it...

I wouldn't want DAC at all, even if we could get it to work. That might be too much for the V30 however.. But, if it did work, the YM3812 in this IBM does sit on a SoundBlaster (8-bit 22khz mono)

TmEE co.(TM) · Post by **TmEE co.(TM)** » Tue May 29, 2007 7:50 am

But SEGA made(and some of us) z80 do it in ASM not QB which is 6 times slower than C and around 8...10 times slower than plain ASM...

evildragon · Post by **evildragon** » Tue May 29, 2007 7:53 am

TmEE co.(TM) wrote:But SEGA made(and some of us) z80 do it in ASM not QB which is 6 times slower than C and around 8...10 times slower than plain ASM...

oh, yea, my bad..

well, the V30 has the complete 80186 instruction set, and some 286 instructions (though it's a 286 overdrive of a sorts, it doesn't seem to have every 286 instruction, so i wouldn't count on that.. i'd count more on it's 8086 instructions)

Mask of Destiny · Post by **Mask of Destiny** » Tue May 29, 2007 1:01 pm

evildragon wrote:
Shiru wrote:OPL and OPN is a different FM synth chips series. They not directly compatible, and has different set of synth abilities.

Main difference: OPN always was 4-op with one osc. waveform (sine); OPL was 2-op (with 4-op modes) and selectable osc. waveforms.
then shouldn't that mean that i should be able to get accurate YM2612 emulation on a 3812? it has the 4 operator mode, and has the sine wave...

The 4-op mode isn't a true 4-op mode. It's closer to two 2-op channels playing at the same t ime than a true 4-op channel. Also, I believe OPL-2 is strictly 2-op only. The pseudo 4-op mode doesn't come into the picture until OPL-3.

evildragon · Post by **evildragon** » Tue May 29, 2007 1:33 pm

Mask of Destiny wrote:
evildragon wrote:
Shiru wrote:OPL and OPN is a different FM synth chips series. They not directly compatible, and has different set of synth abilities.

Main difference: OPN always was 4-op with one osc. waveform (sine); OPL was 2-op (with 4-op modes) and selectable osc. waveforms.
then shouldn't that mean that i should be able to get accurate YM2612 emulation on a 3812? it has the 4 operator mode, and has the sine wave...
The 4-op mode isn't a true 4-op mode. It's closer to two 2-op channels playing at the same t ime than a true 4-op channel. Also, I believe OPL-2 is strictly 2-op only. The pseudo 4-op mode doesn't come into the picture until OPL-3.

is it possible to perhaps interpolate the operators into two? i know it would sound less, but even this Mystic Cave recording I did this morning on a 3812, is pretty good..

(and PS: why is my 3812 so noisy in the morning, and so nice and quiet in the evening? it's freaky!)

http://blackevilweredragon.spymac.com/mystic.mp3

evildragon · Post by **evildragon** » Tue May 29, 2007 2:10 pm

for anyone wanting the files used, to do this on your own YM3812 (or even the OPL3, which I have NOT heard play, yet)

http://blackevilweredragon.spymac.com/YM3812.zip

these are DOSBOX ready.. if you do this on real hardware, make sure you have a YM3812, and the sound card driver installed correctly.. if you don't have a 3812, replace SBFMDRV with the propper driver that goes with your OPL series..

there's one added song in there i haven't recorded, and one missing too...

if there's any files in the zip that begin with a period, or "._", you can delete those.. they are weird things the OS X Finder puts in folders for some reason...

jobro · Post by **jobro** » Wed Jul 11, 2007 5:20 am

The thing is that the chips are very different from eachother. I haven't tested it.

evildragon · Post by **evildragon** » Tue Jul 31, 2007 2:52 am

Ok, how about OPL 3?

I tried music from CastleVania Bloodlines on my OPL 3 and it sound VERY close, but not close enough...