The chips themselves are not compatible with any IBM PC games so there's limited use outside VGM playback and such. PC98 software isn't going to be compatible for a variety of reasons, a lot of patching will be necessary to deal with both hardware and software incompatibilities...

Tiido wrote on 2021-03-21, 01:37:

The chips themselves are not compatible with any IBM PC games so there's limited use outside VGM playback and such. PC98 software isn't going to be compatible for a variety of reasons, a lot of patching will be necessary to deal with both hardware and software incompatibilities...

I'm not worried about compatibility. I would gladly write my own program to support it.

Support in what way ? VGM player and some other music formats player shouldn't be too difficult to do. I'm now thinking how it would be nice if the VGM plugin for winamp/xmplay can be made to support the actual chips on expansion card in a PC, though these chips are very slow to access which will bring some complication to the matter since a lot of CPU time is lost in waiting for the chip to be ready for the next access... FIFO will be able to help though, similar to what most MPU401 interfaces have to reduce the same problem.

Tiido wrote on 2021-03-21, 01:50:

Support in what way ? VGM player and some other music formats player shouldn't be too difficult to do. I'm now thinking how it would be nice if the VGM plugin for winamp/xmplay can be made to support the actual chips on expansion card in a PC, though these chips are very slow to access which will bring some complication to the matter since a lot of CPU time is lost in waiting for the chip to be ready for the next access... FIFO will be able to help though, similar to what most MPU401 interfaces have to reduce the same problem.

Native support in a sound engine I'm working on.

I stick to MSX for VGMPlay usage. Incredibly versatile support for original chips. But very expensive to build a full setup.

For modern PC usage, the Japanese have made both G.I.M.I.C. and Re:Birth. Re:Birth supports more exotic chip setups, while G.I.M.I.C. has built in PCM for simplicity.
Again both are quite expensive to get ahold of though.

TelamonLivesOn wrote on 2021-03-21, 01:27:

I love listening to different chiptune music and like the sound of FM synthesis, but I can't help but feel that the Yamaha OPL chips are quite lacking in character.

I think how OPL3 sounds may depend on a couple of things. Firstly and foremost, was the music specifically made with FM synth in mind, or was it created using a General MIDI device and then converted? Not sure about Wolf3D, but Doom is certainly an example of the latter.

It might also matter how much much filtering is applied to FM synth by the sound card. Something like a SBPro will have slightly warmer, less harsh sounding OPL3 due to the always active low-pass filter. OTOH, a Yamaha YMF7x4 card doesn't apply any filtering to FM synth and can often sound cleaner/harsher.

Here's a track from Tyrian which I recorded on a Yamaha YMF744 card using Digital Out. Doesn't get much cleaner than that, I think.

Joseph_Joestar wrote on 2021-03-21, 06:24:

I think how OPL3 sounds may depend on a couple of things. Firstly and foremost, was the music specifically made with FM synth in […]
Show full quote

TelamonLivesOn wrote on 2021-03-21, 01:27:

I love listening to different chiptune music and like the sound of FM synthesis, but I can't help but feel that the Yamaha OPL chips are quite lacking in character.

I think how OPL3 sounds may depend on a couple of things. Firstly and foremost, was the music specifically made with FM synth in mind, or was it created using a General MIDI device and then converted? Not sure about Wolf3D, but Doom is certainly an example of the latter.

It might also matter how much much filtering is applied to FM synth by the sound card. Something like a SBPro will have slightly warmer, less harsh sounding OPL3 due to the always active low-pass filter. OTOH, a Yamaha YMF7x4 card doesn't apply any filtering to FM synth and can often sound cleaner/harsher.

Here's a track from Tyrian which I recorded on a Yamaha YMF744 card using Digital Out. Doesn't get much cleaner than that, I think.

Sounds very clean. This is what I am talking about: https://www.youtube.com/watch?v=LuNcxehy3pY. It sounds like someone ate too many burritos.

I am really starting to think that the OPL2/3 is very underutilized and that I have been spoiled with great utilization of similar chips. I am wondering if there is any way to create a decent GM -> FM converter. I do like Doom's OST on FM, but some other examples just don't sound good to me.

TelamonLivesOn wrote on 2021-03-21, 01:38:

Tiido wrote on 2021-03-21, 01:37:

The chips themselves are not compatible with any IBM PC games so there's limited use outside VGM playback and such. PC98 software isn't going to be compatible for a variety of reasons, a lot of patching will be necessary to deal with both hardware and software incompatibilities...

I'm not worried about compatibility. I would gladly write my own program to support it.

Well,.. Some DOS/V games use a middleware, PMDIBM.COM, to play FM music.
Personally, I do know of only a few DOS/V games, though.

See https://www.youtube.com/channel/UCM_rzw6WcXib … 22dos%2Fv%22%20

I vaguely remember, there also were combined PC98+DOS/V releases. But I could be wrong.
If that's true, though, they may do contain both OPL3/OPN resources on a single CD or disk set.
So it may be feasible to patch the DOS/V executables to use OPN on a homemade OPN sound card.

By the way, here's some more shameless self-adverising.. 😉

Re: Timeline of MS-DOS for NEC PC98 and more

It's by far not professional or complete, it's just a little overview/brainstorming thingy. 😅
Tiido likely knows more of these things.

Edit: Also interesting : https://www.reddit.com/r/pc98/comments/452bdu … y_and_princess/

Edit : Some DOS/V games from ELF (?) also used "PLAY5V.COM"..

https://forums.anandtech.com/threads/sb-midi- … ur-help.402783/

It's also mentioned at Vogons here, in this ancient thread from 2004 (please don't post, let it RIP 🙂).
OPL3(Yamaha YMF-262) control emulation is defective

I think the only way to end up with decent GM -> FM would be if it's an OPL3 in 4-op mode. At that point it would have 6 voices with better capability than the YM2151/YM2164 found in the Yamaha CX5M/SFG-01/DX21/DX27/DX100/FB-01 since they have selectable waveforms to modulate with or to be modulated. That's 2 fewer than the 2151/2164 has total, but then you also still have 6 2-op channels left over for whatever else. I think if there was any quality way to convert GM to 2-op OPL2 FM then it would have been invented already when that was the only chip people had to work with on the PC platform. I'm willing to believe that area has some space to work with though, since I doubt most implementations used the OPL3-new features besides the doubled number of voices.

If you look at this person's channel, I believe all their OPL3 music is in the 2-op mode since they've said their tracker doesn't support 4-op, at which point you get 18 voices though the the songs use far fewer. OPLx is far less bad than most think.
https://www.youtube.com/channel/UC0KWAt5VoKrDyeDDNO4-_pg
Even just on the OPL2, you can do some decent sounding music, though it's obviously far more limited than the OPL3 or any 4-op FM chip:
https://www.youtube.com/watch?v=vtHMBpbMm2k

OPL3's 4-op mode is an area too poorly explored and it's a real shame. 6 4-op voices and 6 2-op voices.

The Falcosoft MIDI Player has OPL3 GM emulator VSTi which includes source. I believe the OPL3 implementation is based on DOSBOX OPL2/3 and Nuked OPL3 implementations.
Falcosoft Soundfont Midi Player + Munt VSTi + BassMidi VSTi

There's also FMMIDI which plays MIDI files on an emulated Yamaha YM2608 (OPNA).
https://github.com/Menezesworks/fmmidi

You could use either to see how they map GM to FM and create a TSR for DOS that would convert the GM to FM on a soundcard, or a Windows MIDI device driver to do the same.

Fun fact: In Japan (early 90s), MML was an alternative to General MIDI. 😀

Jo22 wrote on 2021-03-21, 18:59:

Fun fact: In Japan (early 90s), MML was an alternative to General MIDI. 😀

I have never heard of that before. Looks like an interesting read.

Error 0x7CF wrote on 2021-03-21, 18:42:

I think the only way to end up with decent GM -> FM would be if it's an OPL3 in 4-op mode. At that point it would have 6 voices […]
Show full quote

I think the only way to end up with decent GM -> FM would be if it's an OPL3 in 4-op mode. At that point it would have 6 voices with better capability than the YM2151/YM2164 found in the Yamaha CX5M/SFG-01/DX21/DX27/DX100/FB-01 since they have selectable waveforms to modulate with or to be modulated. That's 2 fewer than the 2151/2164 has total, but then you also still have 6 2-op channels left over for whatever else. I think if there was any quality way to convert GM to 2-op OPL2 FM then it would have been invented already when that was the only chip people had to work with on the PC platform. I'm willing to believe that area has some space to work with though, since I doubt most implementations used the OPL3-new features besides the doubled number of voices.

If you look at this person's channel, I believe all their OPL3 music is in the 2-op mode since they've said their tracker doesn't support 4-op, at which point you get 18 voices though the the songs use far fewer. OPLx is far less bad than most think.
https://www.youtube.com/channel/UC0KWAt5VoKrDyeDDNO4-_pg
Even just on the OPL2, you can do some decent sounding music, though it's obviously far more limited than the OPL3 or any 4-op FM chip:
https://www.youtube.com/watch?v=vtHMBpbMm2k

OPL3's 4-op mode is an area too poorly explored and it's a real shame. 6 4-op voices and 6 2-op voices.

The goal of my sound engine is to explore and utilize almost all features of any given sound device, along with being able to accept any community-made drivers without having to modify the engine itself. I might look into the extra OPL3 features so that I can utilize them.

AFAIK, very few games used the OPL3 chip to its full potential.

The Cybersphere soundtrack is among those rare examples. That game actually requires OPL3 to work. It's not compatible with OPL2 devices.

Joseph_Joestar wrote on 2021-03-21, 19:19:

AFAIK, very few games used the OPL3 chip to its full potential.

The Cybersphere soundtrack is among those rare examples. That game actually requires OPL3 to work. It's not compatible with OPL2 devices.

I'm hoping that my sound engine can be used with other old games and new projects (with a little tinkering, of course). Imagine Doom with even better FM music.

TelamonLivesOn wrote on 2021-03-21, 19:30:

Imagine Doom with even better FM music.

Well, there is DMXOPL.

I haven't used that myself, but it does sound interesting.

Joseph_Joestar wrote on 2021-03-21, 19:40:

TelamonLivesOn wrote on 2021-03-21, 19:30:

Imagine Doom with even better FM music.

Well, there is DMXOPL.

I haven't used that myself, but it does sound interesting.

That sounds awesome!!!

TelamonLivesOn wrote on 2021-03-21, 01:27:

Years later, I tried the game on MAME, but felt that something about the sound was off.

If you haven't tried lately, you may want to try again later this month (or now, if you can compile your own). OPN emulation improvements went into MAME just a few weeks ago and will be released with MAME 0.230. We're hoping that MAME 0.230 will have OPL family improvements as well, but that might get pushed back until MAME 0.231, we'll see!