Digital Audio playback from a Yamaha OPL2/3 chip

[Cloudschatze]

Well, this took me by surprise.

Yesterday evening I was doing some comparisons between the SoundBlaster Pro 2 and Pro AudioStudio, and happened to load a game given me by my brother-in-law, which I thought had SB support (the box has an "AdLib-Supported" sticker) -

Capstone's "Bill and Ted's Excellent Adventure."

Radical, huh?

...

Anyway, the game begins with a looping piece, which I initially thought was a combination of an FM melody with PCM drum samples. Desiring to test this theory, I muted the FM volume - nothing played. Restoring the FM volume, I then muted the SB DAC - everything played.

I performed the same test on the PAS16 card in a separate PC. With the SB-compatible hardware completely disabled, it produced the same result - PCM samples (including vocal snippets, sfx) are being played through the OPL chip.

I've done some Google searching, and have found very little supportive evidence to back this up, though I did find two claims that "Space Ace" does the same.

Just thought I'd share. If there are any other games which play digital audio through the OPL, I would love to hear about them.

Additionally, I would be very interested to know if the CSM (Composite Sinusoidal Modeling) mode of the OPL2 chip has ever been utilized.

[Cloudschatze]

Here is an mp3 recording, for any interested folk.

All that from what essentially comprises an AdLib card - How cool is that?

[Tom]

That IS cool!  I had thought I remembered something like that being done with "Rocket Ranger", "Defender Of The Crown", and "The Three Stooges", playing through my Ad Lib card on my old Tandy.  One or two of those old Cinemaware games.  I could be mistaken, but it sure sound familiar.  Damn, I loved Rocket Ranger!  Played it constantly!

[Laust]

It's the same technique used to play samples through the PC speaker. A handful of games used it, but since it ties up the CPU and wasn't very practical it never found widespread use.

[Ari]

Maybe this is the same thing that happens in SQ3 where you can hear Roger saying "Where am I??" in the intro.

[HondaSiR]

It's the same technique used to play samples through the PC speaker. A handful of games used it

I believe it was called RealSound back then and used by Access Software, IIRC. Quite a novelty back in those days but didn't quite catch on. You needed to amplify the speaker's output because the process lowers the volume considerably.

[Cloudschatze]

Stefan Göhler's "Phonomenal!" article mentions the sample-playback capability of the AdLib card:

"It is also interesting to know that later some software (specifically tools for the MOD-Wiedergabe) but also some games, applied quite similar tricks like with the PC Speaker, and so actually originated a qualitative relatively appealing sample playback."

You know, perhaps the part about "actually originated a qualitative relatively appealing" threw me off, but I'm fairly certain I've read the article at least two times prior, and only now understand what he was getting at.

[gortmertl0]

Maybe this is the same thing that happens in SQ3 where you can hear Roger saying "Where am I??" in the intro.

Back in mid-1991, I was amazed when a college friend showed me the SQ3 Intro where Roger speaks that single digitized line on his old Tandy PC...  From a game that came on 5-1/4" floppies, no less!

He was always proud how the Tandy PCs could do a little bit more using the PC speaker than the average IBM clone.

I was debating on getting a Sound Blaster card at the time for my dad's 286-12Mhz at the time, dreaming of the possibilities of actual sound... (Was it an 8-bit?  It was the card that for $30 more, you could order an add-on chip so it would play in stereo, as opposed to mono.)

[jbltecnicspro]

Yeah, I'm not surprised that the Adlib can do this.  Virtually any CPU can generate sound...  For example, did you know that Texas Instruments Graphing calculators (TI-83+ and up) can do the same thing?  Not only can they generate squarewave synthesis, but they can playback digital files too.  Playing digital sound on the calculators is only cool for experimentation, really.  Since the calcs have limited RAM, the max song length is like 15 seconds, and the bitrate is 6 bits sound (like the IBM PC).  Since my TI-89 has more RAM, it can play a full minute, but again, it's just for experimentation.

In fact, I'm sure that the MT-32 could do this, but since the sound generators are pushing code so fast, its CPU might lock up and give an overflow error.  Hmm, I wonder if the CM models, since they don't have the slow-CPU problem, could actually do something neat with this?  After all, a single partial could create a sound, thus, making the units a 32-channel digital sound source.  I have no doubt that the thing could at least produce an 8-bit quality sound (which isn't awesome, but isn't terrible).  Just a thought.

[Cloudschatze]

Hmm, I wonder if the CM models, since they don't have the slow-CPU problem, could actually do something neat with this?

It's a neat idea, but not easily possible for a host of reasons. Chiefly, the computer does not have "direct" access to the MT-32; communication is all done via MIDI.

The MPU-401/IPC/etc. breakout boxes have a metronome tweeter though, and while I'm not sure if it would be possible even with this, I still wonder that the external beeper was never utilized by any gaming software (if only for the sake of novelty).

[jbltecnicspro]

Hmm, I wonder if the CM models, since they don't have the slow-CPU problem, could actually do something neat with this?

It's a neat idea, but not easily possible for a host of reasons. Chiefly, the computer does not have "direct" access to the MT-32; communication is all done via MIDI.
quote]

Well, the CM would have to be set up using a sysex.  Say, make patches that just use one partial for pure synthesis.  Then, sampled songs could be sent at a high frequency and at a very high speed.  

Also, is there anyway that Sysex could play a song?  As in, instead of using Sysex to just remap patches and upload patches, use sysex to do the sampling?

[jbltecnicspro]

Also, the LAPC is directly connected to the PC, but since it is MIDI, I would assume it would have the same bottleneck?

[Cloudschatze]

Well, the CM would have to be set up using a sysex.  Say, make patches that just use one partial for pure synthesis.  Then, sampled songs could be sent at a high frequency and at a very high speed.

Without some serious hardware hacking involved, this is just not possible. There are no (documented) SysEx strings to allow such a feat.

Also, is there anyway that Sysex could play a song?  As in, instead of using Sysex to just remap patches and upload patches, use sysex to do the sampling?

I'm not sure what you mean by sampling, but if you're asking if it's possible to include Note Events in a SysEx string, the answer is no; it wouldn't be SysEx otherwise.

As far as the LAPC-I goes, yeah, you have the same constraint. The PC interfaces with the on-board MPU, which communicates with the synth via MIDI.

[jbltecnicspro]

Damn, oh well.  I thought it might be cool to do this.

[BlueMax]

I remember another game that did it too - it was a "Simpsons" game where you played Bart and eventiully battled it out against Sideshow Bob.

It would play digital samples through AdLib (all I had at the time, no SB) but would freeze the action in order to do so, just like the PC speaker did.  If you had a SoundBlaster, samples would play without stopping.  

MT-32 would NOT play samples.

[NewRisingSUn]

Anyway, the game begins with a looping piece, which I initially thought was a combination of an FM melody with PCM drum samples.

How many PC games actually do use OPL FM with PCM drums? That technique is ubiquitous on Japanese consoles and computers, but the only PC game I can think of is that odd polygon-based "World Tour Tennis" game.

Maybe this is the same thing that happens in SQ3 where you can hear Roger saying "Where am I??" in the intro.

No, Sierra uses normal DMA-based DAC playback, both on the Tandy and Sound Blaster.

Also, is there anyway that Sysex could play a song? As in, instead of using Sysex to just remap patches and upload patches, use sysex to do the sampling?

Roland system exclusive messages don't do anything other than store data into strictly defined fields of the control program's work memory.

[Laust]

Anyway, the game begins with a looping piece, which I initially thought was a combination of an FM melody with PCM drum samples.

How many PC games actually do use OPL FM with PCM drums? That technique is ubiquitous on Japanese consoles and computers, but the only PC game I can think of is that odd polygon-based "World Tour Tennis" game.

Zone 66 and Gods (though it isn't sampled drums but voice samples, the principle is the same) come to mind. A few demos by the same people that made Zone 66 also use it (including the famous Amnesia demo), but no it never caught on.

Is World Tour Tennis the same as International 3D Tennis on the C64?

[BlueMax]

Nooooopenopenope.  Zone66 used the Soundblaster to its utmost by combining 4-channel MOD music (maybe 8?) along with the FM synth.

GUS users only got the samples.
Adlib users only got the FM.

The Adlib wasn't doing any sample plyback that time....

[Laust]

Nooooopenopenope.  Zone66 used the Soundblaster to its utmost by combining 4-channel MOD music (maybe 8?) along with the FM synth.

GUS users only got the samples.
Adlib users only got the FM.

The Adlib wasn't doing any sample plyback that time....

I'm well aware of exactly what Zone 66 does - I was answering NewRisingSun's question about which games used FM and PCM samples at the same time and not the original premise of this thread. I don't think he was asking about games that used the FM chip for playing samples, especially when making a reference to Japanese platforms (a lot of which had dedicated sample playback hardware and no need for tricks).

[NewRisingSUn]

Is World Tour Tennis the same as International 3D Tennis on the C64?

No, that's a completely different game. "World Tour Tennis" was released in some countries as "4D Sports Tennis", and is by Distinctive Software. It uses PCM drums and Orchestra Hits, although both are just sampled from the MT-32. I just noticed that "4D Sports Boxing" also uses PCM drums in such a way.

I still don't know whether that company's main development platform was the PC or the Amiga. Test Drive and Grand Prix Circuit both look and sound better on Amiga, but according to the release schedule, the PC versions always came first. The "4D Sports" games look very Amiga-32 color-like on the PC, but are ridiculously slow on the Amiga.