MPU-401 is just a MIDI interface. It's a way of transmitting MIDI data between computer and other hardware (i.e. sound modules).

The MT-32 is a sound module based on Roland's LA synthesizer technology. In order to connect it to a computer, you need an MPU-401 interface (and preferably one with "intelligent mode" capability).

The Roland LAPC-I (or LAPC-1) is an internal sound card similar to the MT-32, but it also includes a built-in MPU-401 interface. This means you can connect additional sound modules using the LAPC-I provided you also have the proprietary MIDI connector box, the MCB-1.

Insofar as legal options, I believe that original hardware is your only option if you want to be 100% legal. The issue is the copyright of the ROM files used in the MT-32, and ownership by Roland.

Alright, thanks a lot! This is what I feared, but it is what it is. Might rather use the amiga version of MM3 then ^^

Might & Magic 3 sound effects are more complete on Adlib/SB than MT-32. On MT-32 you get music and a very limited set of SFX and they don't sound great either.
What MM3 needs is LAPC-1 or CM-32 which include a few additional SFX instruments used by the game (foot steps, water pouring, ...).

The game also needs intelligent MPU-401 mode. But also it only works on a real MPU-401 compatible HW. SoftMPU makes the game run at snail speed (like 2 seconds-per-frame).

Sorry to break the bad news here. I believe the cheapest way to get full MT-32 capabilities of this game is DOSBox and MUNT... AND I'm not sure how legal is to feed MUNT the dumped MT-32 ROMs either.

Speed-wise, this game is best played on a 486 25/33 Mhz. 486 66MHz is already too fast and it shows in the frantic scenery animations. I found 386 33MHz to be on the slower side, so yeah. 486 DX 25/33 it is in my book... just like can be seen in this installation video:
https://youtu.be/WRe9CORKOng

For all these things, keep an eye out on classified ads for musicians. The old Roland modules are highly sought-after and becoming expensive if not downright unobtainium in vintage computing circles. However they are old trash to many musicians and if musicians in question (or ther heirs after they die, as is sadly quite common now) either don't know or don't care about the hype you can still get them dirt cheap. I've gotten hold of both a Roland SC55ST and a Yamaha MU50 for less than EUR 50 each that way. Same applies to the interface cards. I have an MPU401AT and two MusicQuest clones that cost max EUR 25 each (the MPU401AT was in a 'trash load' for EUR 5, identified by its characteristic mini-DIN connectors in a potatocam shot...). I even once found an MT-100 (=late model MT-32 with added sequencer functionality, fully usable as MT-32) that way for EUR 55, although as I already had an MT-32 (that I did pay quite a bit for, but back when it wasn't as bad as now) I part-traded that for other interesting stuff later.

So be patient and be observant and check ads and you can still find affordable options.

wbahnassi wrote on 2024-08-05, 12:38:

Might & Magic 3 sound effects are more complete on Adlib/SB than MT-32. On MT-32 you get music and a very limited set of SFX and […]
Show full quote

Might & Magic 3 sound effects are more complete on Adlib/SB than MT-32. On MT-32 you get music and a very limited set of SFX and they don't sound great either.
What MM3 needs is LAPC-1 or CM-32 which include a few additional SFX instruments used by the game (foot steps, water pouring, ...).

The game also needs intelligent MPU-401 mode. But also it only works on a real MPU-401 compatible HW. SoftMPU makes the game run at snail speed (like 2 seconds-per-frame).

Sorry to break the bad news here. I believe the cheapest way to get full MT-32 capabilities of this game is DOSBox and MUNT... AND I'm not sure how legal is to feed MUNT the dumped MT-32 ROMs either.

Speed-wise, this game is best played on a 486 25/33 Mhz. 486 66MHz is already too fast and it shows in the frantic scenery animations. I found 386 33MHz to be on the slower side, so yeah. 486 DX 25/33 it is in my book... just like can be seen in this installation video:
https://youtu.be/WRe9CORKOng

The best experience I saw there was actually on an emulated DosBox version with Roland installed. But this wasn't a "legit" version, but the sounds were much better than on Soundblaster/Adlib, which are cut off, even if emulation is switched towards that. In fact even on Amiga it sounds better in Combat. What comparison videos never show is combat. It just sounds horrific on Soundblaster/Adlib.
Regarding speed MM3 is a horrible mess: Because of it's turnbased nature you can play it with almost all machines, but it's up to you how to finetune it.
If you run it too fast, then: Animations are too fast, Movement is too fast (if you click with mouse on the screen), Sound is too fast.

If you gradually slow it down, first the animations and movement get ok. But at that point you are already at a point where it can be considered hardly playable and where it feels bad.
The cut off sounds can be fixed be reaching a speed where you are at about 1-2 fps. With about 4 fps, they still sound bad but you can hear a clear improvement. But with 4 fps it's also clearly unplayable.

But the animations are purely cosmetical and if you control with keyboard you dont have issues with that either. It's all down to the combat sound. If roland isn't a legitimate option, I will probably wait and play the game in Amiga Emulation at some point. As I am also doing LPs and whatnot I want to use legitimate versions whereever possible.

Kordanor wrote on 2024-08-05, 13:54:

The best experience I saw there was actually on an emulated DosBox version with Roland installed. But this wasn't a "legit" vers […]
Show full quote

wbahnassi wrote on 2024-08-05, 12:38:

Might & Magic 3 sound effects are more complete on Adlib/SB than MT-32. On MT-32 you get music and a very limited set of SFX and […]
Show full quote

Might & Magic 3 sound effects are more complete on Adlib/SB than MT-32. On MT-32 you get music and a very limited set of SFX and they don't sound great either.
What MM3 needs is LAPC-1 or CM-32 which include a few additional SFX instruments used by the game (foot steps, water pouring, ...).

The game also needs intelligent MPU-401 mode. But also it only works on a real MPU-401 compatible HW. SoftMPU makes the game run at snail speed (like 2 seconds-per-frame).

Sorry to break the bad news here. I believe the cheapest way to get full MT-32 capabilities of this game is DOSBox and MUNT... AND I'm not sure how legal is to feed MUNT the dumped MT-32 ROMs either.

Speed-wise, this game is best played on a 486 25/33 Mhz. 486 66MHz is already too fast and it shows in the frantic scenery animations. I found 386 33MHz to be on the slower side, so yeah. 486 DX 25/33 it is in my book... just like can be seen in this installation video:
https://youtu.be/WRe9CORKOng

The best experience I saw there was actually on an emulated DosBox version with Roland installed. But this wasn't a "legit" version, but the sounds were much better than on Soundblaster/Adlib, which are cut off, even if emulation is switched towards that. In fact even on Amiga it sounds better in Combat. What comparison videos never show is combat. It just sounds horrific on Soundblaster/Adlib.
Regarding speed MM3 is a horrible mess: Because of it's turnbased nature you can play it with almost all machines, but it's up to you how to finetune it.
If you run it too fast, then: Animations are too fast, Movement is too fast (if you click with mouse on the screen), Sound is too fast.

If you gradually slow it down, first the animations and movement get ok. But at that point you are already at a point where it can be considered hardly playable and where it feels bad.
The cut off sounds can be fixed be reaching a speed where you are at about 1-2 fps. With about 4 fps, they still sound bad but you can hear a clear improvement. But with 4 fps it's also clearly unplayable.

But the animations are purely cosmetical and if you control with keyboard you dont have issues with that either. It's all down to the combat sound. If roland isn't a legitimate option, I will probably wait and play the game in Amiga Emulation at some point. As I am also doing LPs and whatnot I want to use legitimate versions whereever possible.

I mean going legit is going to cost , you could try yahoo auctions , this stuff usually goes for alot less over there provided the shipping to your country isn't too much. Other than that a mt32 pi is morally Grey but alot cheaper.

Also if speed is a issue , look into throttle blaster , I just built and tested one and managed to clock my pc down to 4.77 mhz then all the way back through to 233 , it should let you dial the game to the optimal speed.

Thanks, yeah, will have an eye on auctions then, and maybe consider the m32 pi.
Speed is not really an issue in itself as described below. There is no "optimal setting". With the 4.77Mhz you mention, it's probably still too fast for the sound, and completely unplayable otherwise. With the lowest speed I can Deal in with my machine (AMD k6 2+ 570Mhz down to 386 25Mhz) it's already feeling too slow in some regard, while animations are still a bit too fast, as well as movement. But it's not an issue as I would play with keyboard anyways.
The main issue is the sound, which was possibly just accepted that way back then (same as most people will not even have realized that Burntime had voice acting), but to me it just sounds wrong an buggy and would kill the enjoyment.

The PicoGUS is an incredible option as it not only gives you an intelligent mode MPU401 that's needed for the MT-32, but also access to a GUS, Tandy 3 Voice, and CMS/GameBlaster.

But as other have said there's no "cheap" and "legal" way. There are emulators but they rely on Roland's copyrighted ROMs. Roland does still have an option to buy a digital Sound Canvas application. But it needs to run on modern hardware, and emulates a newer modules so the sound isn't the same as a real SC-55. The MT-32 you are stuck with buying original hardware.

If you haven't experienced the MT-32 or a Sound Canvas. You really should just try things out with DOSBox or Munt for the MT-32. And use the new in development Nuked SC-55 emulator to at least experience them. You can then decide how much you really like them. With the MT-32 Roland hasn't sold it for something like 25 years, just buy a Roland UM One USB MIDI cable to connect your retro PC to another PC running MUNT and Nuked SC-55. That way Roland was paid, and you can play experience the modules with your retro PCs.

SScorpio wrote on 2024-08-05, 15:14:

The PicoGUS is an incredible option as it not only gives you an intelligent mode MPU401 that's needed for the MT-32, but also access to a GUS, Tandy 3 Voice, and CMS/GameBlaster.

But as other have said there's no "cheap" and "legal" way. There are emulators but they rely on Roland's copyrighted ROMs. Roland does still have an option to buy a digital Sound Canvas application. But it needs to run on modern hardware, and emulates a newer modules so the sound isn't the same as a real SC-55. The MT-32 you are stuck with buying original hardware.

If you haven't experienced the MT-32 or a Sound Canvas. You really should just try things out with DOSBox or Munt for the MT-32. And use the new in development Nuked SC-55 emulator to at least experience them. You can then decide how much you really like them. With the MT-32 Roland hasn't sold it for something like 25 years, just buy a Roland UM One USB MIDI cable to connect your retro PC to another PC running MUNT and Nuked SC-55. That way Roland was paid, and you can play experience the modules with your retro PCs.

I just ordered the Orpheus 2 LT as I read that it might the last batch. I ordered it not for the MPU401, but for the Sound Blaster features with clean sound. But it does come with MPU401 as well, which also has an intelligent mode. I think it will basically do the same as the PicoGUS, right? Besides of it being "real hardware" while the PicoGUS is emulation (which also has its advantages I guess. Maybe because of being emulation the PicoGus would even ignore the cut off SB sounds 😁 )

I am not particularly interested in the MT32 Sound to be honest. I do think it sounds "objectively" better if that makes sense, but to me SB is what I, and most other people grew up with, and have most nostalgia for (which is also why I am not interested in the GUS). However in case of some games (like MM3, where SB sound is basically "broken") my nostalgia doesn't outweigh the brokenness of the sound. As mentioned I'd rather play it on amiga then. The MT32-Pi does sound like an interesting option, even though from a legal standpoint it's probably as bad. I am not sure if it would work in the case of MM3. Maybe @wbahnassi can tell?

Kordanor wrote on 2024-08-05, 15:46:

I just ordered the Orpheus 2 LT as I read that it might the last batch. I ordered it not for the MPU401, but for the Sound Blaster features with clean sound. But it does come with MPU401 as well, which also has an intelligent mode. I think it will basically do the same as the PicoGUS, right? Besides of it being "real hardware" while the PicoGUS is emulation (which also has its advantages I guess. Maybe because of being emulation the PicoGus would even ignore the cut off SB sounds 😁 )

I am not particularly interested in the MT32 Sound to be honest. I do think it sounds "objectively" better if that makes sense, but to me SB is what I, and most other people grew up with, and have most nostalgia for (which is also why I am not interested in the GUS). However in case of some games (like MM3, where SB sound is basically "broken") my nostalgia doesn't outweigh the brokenness of the sound. As mentioned I'd rather play it on amiga then. The MT32-Pi does sound like an interesting option, even though from a legal standpoint it's probably as bad. I am not sure if it would work in the case of MM3. Maybe @wbahnassi can tell?

The Orpheus 2 LT supposedly has excellent sound but it's $210 Euro for a sound blaster / adlib / MPU401. It doesn't have GUS, Tandy 3 Voice, or CMS that the PicoGUS brings at a much, much cheaper price point. The full Orpheus 2 adds GUS support for an additional $130 Euro.

I'm confused in that you were asking about budget hardware and then seem to being buying enthusiast/audiophile priced pieces. You could use your existing Sound Blaster and/or ESS card and have spent less on a real Sound Canvas SC-55. And you spent around the price of an MT-32.

SScorpio wrote on 2024-08-05, 16:35:

Kordanor wrote on 2024-08-05, 15:46:

I just ordered the Orpheus 2 LT as I read that it might the last batch. I ordered it not for the MPU401, but for the Sound Blaster features with clean sound. But it does come with MPU401 as well, which also has an intelligent mode. I think it will basically do the same as the PicoGUS, right? Besides of it being "real hardware" while the PicoGUS is emulation (which also has its advantages I guess. Maybe because of being emulation the PicoGus would even ignore the cut off SB sounds 😁 )

I am not particularly interested in the MT32 Sound to be honest. I do think it sounds "objectively" better if that makes sense, but to me SB is what I, and most other people grew up with, and have most nostalgia for (which is also why I am not interested in the GUS). However in case of some games (like MM3, where SB sound is basically "broken") my nostalgia doesn't outweigh the brokenness of the sound. As mentioned I'd rather play it on amiga then. The MT32-Pi does sound like an interesting option, even though from a legal standpoint it's probably as bad. I am not sure if it would work in the case of MM3. Maybe @wbahnassi can tell?

The Orpheus 2 LT supposedly has excellent sound but it's $210 Euro for a sound blaster / adlib / MPU401. It doesn't have GUS, Tandy 3 Voice, or CMS that the PicoGUS brings at a much, much cheaper price point. The full Orpheus 2 adds GUS support for an additional $130 Euro.

I'm confused in that you were asking about budget hardware and then seem to being buying enthusiast/audiophile priced pieces. You could use your existing Sound Blaster and/or ESS card and have spent less on a real Sound Canvas SC-55. And you spent around the price of an MT-32.

Well I think I layed out the situation in the initial post, where I alo mentioned that I was considering the Orpheus II LT anyways. This is to maximize Sound quality for SB, which is what I use for 99% of all games. If the game supports proper SB/Adlib sound I have no interest of using MT32 nor GUS. As GUS is newer than SB/Adlib I also doubt that there are many cases where this is an option where SB/Adlib is not. In terms of MT32 there are going to be games which either dont support Adlib/SB or are broken, like MM3. I would like to play these as well. But I am also not willing to pay 300-400€ just to play MM3 and a few other games. (While at the same time I am fine, even though it hurts, to pay 210€ for a card which I will be using in basically 99% of all games)

Also from what I understand it doesn't matter how you get the MPU401 (as long as it got intelligent mode), as you will always need to buy the external Roland device for 300€+. So whether I bought this card or a cheap used card featuring MPU410 would not have made a difference, not getting around the 300€. Unless going for the mt32 pi which applesauce suggested and which I wasnt aware of.

I would have hoped that there is something like the PicoGUS which already had the Roland Emulation (like a full mt32 PI) included - not just the interface.

Kordanor wrote on 2024-08-05, 16:55:

I would have hoped that there is something like the PicoGUS which already had the Roland Emulation (like a full mt32 PI) included - not just the interface.

There was the Roland LAPC-I which was an ISA card that had a MT-32 onboard. But no one has cloned that.

Instead there's the MT-32 McCake which runs the MT-32 Pi software on a MIDI daughter board that will worth with a large number of sound cards. https://www.serdashop.com/WP32-McCake

Intelligent mode is needed by some games for the MT-32 but not all, and the games require it are older and work fine with extended memory so you can use SoftMPU with pretty much any sound card. At this time that will get you MT-32 and as well as General MIDI support with soundfonts. It's currently unknown what will happen with the Nuked SC-55 project, but last I heard the creator of the MT-32 Pi project had issues with the license the SC-55 project was using and wasn't looking into trying to get it working with MT-32 Pi.

SScorpio wrote on 2024-08-05, 19:51:

There was the Roland LAPC-I which was an ISA card that had a MT-32 onboard. But no one has cloned that. […]
Show full quote

Kordanor wrote on 2024-08-05, 16:55:

I would have hoped that there is something like the PicoGUS which already had the Roland Emulation (like a full mt32 PI) included - not just the interface.

There was the Roland LAPC-I which was an ISA card that had a MT-32 onboard. But no one has cloned that.

Instead there's the MT-32 McCake which runs the MT-32 Pi software on a MIDI daughter board that will worth with a large number of sound cards. https://www.serdashop.com/WP32-McCake

Intelligent mode is needed by some games for the MT-32 but not all, and the games require it are older and work fine with extended memory so you can use SoftMPU with pretty much any sound card. At this time that will get you MT-32 and as well as General MIDI support with soundfonts. It's currently unknown what will happen with the Nuked SC-55 project, but last I heard the creator of the MT-32 Pi project had issues with the license the SC-55 project was using and wasn't looking into trying to get it working with MT-32 Pi.

Oh, that sounds promising at least. 😀
MM3 explicitly asks for a Roland LAPC-I (screenshot in first post), but can it be assumed that it then also just runs on any other MPU-401 device?
The MT-32 McCake looks like a nice option!

Kordanor wrote on 2024-08-05, 20:04:

SScorpio wrote on 2024-08-05, 19:51:

There was the Roland LAPC-I which was an ISA card that had a MT-32 onboard. But no one has cloned that. […]
Show full quote

Kordanor wrote on 2024-08-05, 16:55:

I would have hoped that there is something like the PicoGUS which already had the Roland Emulation (like a full mt32 PI) included - not just the interface.

There was the Roland LAPC-I which was an ISA card that had a MT-32 onboard. But no one has cloned that.

Instead there's the MT-32 McCake which runs the MT-32 Pi software on a MIDI daughter board that will worth with a large number of sound cards. https://www.serdashop.com/WP32-McCake

Intelligent mode is needed by some games for the MT-32 but not all, and the games require it are older and work fine with extended memory so you can use SoftMPU with pretty much any sound card. At this time that will get you MT-32 and as well as General MIDI support with soundfonts. It's currently unknown what will happen with the Nuked SC-55 project, but last I heard the creator of the MT-32 Pi project had issues with the license the SC-55 project was using and wasn't looking into trying to get it working with MT-32 Pi.

Oh, that sounds promising at least. 😀
MM3 explicitly asks for a Roland LAPC-I (screenshot in first post), but can it be assumed that it then also just runs on any other MPU-401 device?

Yes and no.

As already explained, MIDI is essentially a notation protocol. "Play instrument X at tone Y for duration Z". MIDI itself or the MPU-401 don't care what instrument X is. So feed MIDI from software supporting LACP-I to any other MIDI synth and you will get sound. But..

In the early 1990s, General MIDI was introduced as a standard mapping of instruments, so 1 is an acoustic grand piano and 128 a gunshot. It still doesn't say *how* each instrument should sound, so you get differences between synths, but at least you can be sure that hardware supporting GM will (in GM mode) give you the right instruments when you use software supporting GM. Unfortunately LAPC-I and MT-32 are pre-GM. So their mapping does not correspond to GM. 1 is still an acoustic piano but 128 is a "jungle tune". Music will sound as if played through the wrong instruments. Moreover MT-32 and equivalent actually have additional functionality that GM synths don't have, to make new custom sounds. So if your software supports LAPC-I or MT-32 and uses these functionality it will miss sounds.

With more modern GM synths, the option to look for in games is "General MIDI" or "Roland SC-55" or "Roland SCC-1" (and yes, first rev SC-55 is not exactly GM, but let's not go down that rabbit hole unless needed).

So yes, you will get sound, but no, if it's not an LACP-I, CM-32L or CM-500 it won't be perfect and if it's not one of those or MT-32 or MT-100 it will sound utterly wrong.

dionb wrote on 2024-08-06, 11:16:

Yes and no. […]
Show full quote

Kordanor wrote on 2024-08-05, 20:04:

SScorpio wrote on 2024-08-05, 19:51:

There was the Roland LAPC-I which was an ISA card that had a MT-32 onboard. But no one has cloned that.

Instead there's the MT-32 McCake which runs the MT-32 Pi software on a MIDI daughter board that will worth with a large number of sound cards. https://www.serdashop.com/WP32-McCake

Intelligent mode is needed by some games for the MT-32 but not all, and the games require it are older and work fine with extended memory so you can use SoftMPU with pretty much any sound card. At this time that will get you MT-32 and as well as General MIDI support with soundfonts. It's currently unknown what will happen with the Nuked SC-55 project, but last I heard the creator of the MT-32 Pi project had issues with the license the SC-55 project was using and wasn't looking into trying to get it working with MT-32 Pi.

Oh, that sounds promising at least. 😀
MM3 explicitly asks for a Roland LAPC-I (screenshot in first post), but can it be assumed that it then also just runs on any other MPU-401 device?

Yes and no.

As already explained, MIDI is essentially a notation protocol. "Play instrument X at tone Y for duration Z". MIDI itself or the MPU-401 don't care what instrument X is. So feed MIDI from software supporting LACP-I to any other MIDI synth and you will get sound. But..

In the early 1990s, General MIDI was introduced as a standard mapping of instruments, so 1 is an acoustic grand piano and 128 a gunshot. It still doesn't say *how* each instrument should sound, so you get differences between synths, but at least you can be sure that hardware supporting GM will (in GM mode) give you the right instruments when you use software supporting GM. Unfortunately LAPC-I and MT-32 are pre-GM. So their mapping does not correspond to GM. 1 is still an acoustic piano but 128 is a "jungle tune". Music will sound as if played through the wrong instruments. Moreover MT-32 and equivalent actually have additional functionality that GM synths don't have, to make new custom sounds. So if your software supports LAPC-I or MT-32 and uses these functionality it will miss sounds.

With more modern GM synths, the option to look for in games is "General MIDI" or "Roland SC-55" or "Roland SCC-1" (and yes, first rev SC-55 is not exactly GM, but let's not go down that rabbit hole unless needed).

So yes, you will get sound, but no, if it's not an LACP-I, MT-32 (or MT-100 or CM-500) it will sound utterly wrong.

I get that 401 is a protocol, which then sends signals and the signals turn into stuff depending on what is connected there.
But I am wondering whether a any card which in theory is 401 capable can be used, when the sound config explicity asks for Roland LAPC-I, or if it's just like "Nope, No Roland LAPC-I found, no MP 401 for you!".

So yes, you will get sound, but no, if it's not an LACP-I, MT-32 (or MT-100 or CM-500) it will sound utterly wrong.

But isnt the LACP-I the card, and the MT-32 the actual external "box"?

Kordanor wrote on 2024-08-06, 11:27:

[...]

I get that 401 is a protocol, which then sends signals and the signals turn into stuff depending on what is connected there.
But I am wondering whether a any card which in theory is 401 capable can be used, when the sound config explicity asks for Roland LAPC-I, or if it's just like "Nope, No Roland LAPC-I found, no MP 401 for you!".

You get MPU-401. The game tells the MPU-401 interface to play instrument 128. The MPU-401 transmits that command to your MIDI synth and it plays instrument 128.

Only problem is that you were supposed to get a jungle sound because the game uses LAPC-I instrument map and instead you hear a gunshot because the synth uses a GM map.

But isnt the LACP-I the card, and the MT-32 the actual external "box"?

Card or box doesn't matter. LAPC-I is an MPU-401 interface with the guts of a CM-32L on the card. It is functionally identical to an MPU-401 interface connected to an external CM-32L. The CM-32L is almost but not quite identical to the MT-32, but they are very closely related and usually sound about the same (again, bit of a rabbit hole, but not relevant for the big picture).

Similarly the Roland MT-55 module and SCC-1 are functionally identical, the latter being an ISA card with MPU-401 and the synth components of an MT-55 on it. Similarly the SCB-55 is exactly the same synth on a Wavaeblaster daughterboard for a sound card. How it's hooked up doesn't matter, it will work the same and sound the same.

If you're willing to do your own soldering, maybe HardMPU + mt32-pi is a good choice.

dionb wrote on 2024-08-06, 11:56:

You get MPU-401. The game tells the MPU-401 interface to play instrument 128. The MPU-401 transmits that command to your MIDI sy […]
Show full quote

Kordanor wrote on 2024-08-06, 11:27:

[...]

I get that 401 is a protocol, which then sends signals and the signals turn into stuff depending on what is connected there.
But I am wondering whether a any card which in theory is 401 capable can be used, when the sound config explicity asks for Roland LAPC-I, or if it's just like "Nope, No Roland LAPC-I found, no MP 401 for you!".

You get MPU-401. The game tells the MPU-401 interface to play instrument 128. The MPU-401 transmits that command to your MIDI synth and it plays instrument 128.

Only problem is that you were supposed to get a jungle sound because the game uses LAPC-I instrument map and instead you hear a gunshot because the synth uses a GM map.

But isnt the LACP-I the card, and the MT-32 the actual external "box"?

Card or box doesn't matter. LAPC-I is an MPU-401 interface with the guts of a CM-32L on the card. It is functionally identical to an MPU-401 interface connected to an external CM-32L. The CM-32L is almost but not quite identical to the MT-32, but they are very closely related and usually sound about the same (again, bit of a rabbit hole, but not relevant for the big picture).

Similarly the Roland MT-55 module and SCC-1 are functionally identical, the latter being an ISA card with MPU-401 and the synth components of an MT-55 on it. Similarly the SCB-55 is exactly the same synth on a Wavaeblaster daughterboard for a sound card. How it's hooked up doesn't matter, it will work the same and sound the same.

Alright, I think what I missed / didnt get before is that I assumed that the LAPC-I was just another MPU-401 interface, while in fact, it's a completely integrated solution which would not need any additional external device.
So coming from MM3 which "requires" a Roland LAPC-I, I would basically "mimic" the device by having MPU-401 and a CM-32L / MT-32 separately.

Kordanor wrote on 2024-08-06, 12:14:

[...]
Alright, I think what I missed / didnt get before is that I assumed that the LAPC-I was just another MPU-401 interface, while in fact, it's a completely integrated solution which would not need any additional external device.
So coming from MM3 which "requires" a Roland LAPC-I, I would basically "mimic" the device by having MPU-401 and a CM-32L / MT-32 separately.

To perfectly 'mimic' the LAPC-I you would need either that card or a CM-32L or CM-500 CM-64 module.
An MT-32 or MT-100 would come very close, just might miss the odd instrument. I've personally never been able to hear the difference tbh, so for me "good enough". CM-500 would also come very close but different vibrato.

Edit: was mixing up CM-500 and CM-64, tnx for correction Shponglefan

Anything else would not come close; some later Roland synths (SC-55 etc) have an "MT-32 mode" which remaps the instruments to MT-32 map, but they still don't sound like the MT-32 and they can't make the custom sounds. Still, better than nothing.

As for the MPU-401: the original MPU-401 had two modes: Intelligent mode and UART mode. Almost all later MIDI uses UART mode so almost all later MPU-401 implementations only offer that. But... a lot of the old MT-32/LAPC-I stuff requires intelligent mode - and yes, MM3 is one of them of course.

There are two ways to get this:
1) an MPU-401-compatible card that supports intelligent mode.
2) an MPU-401-compatible card that only supports UART mode, in combination with SoftMPU emulation software.

As for the former, the original Roland MPU-401 series (and the integrated LAPC-I, SCC-1 but not RAP-10 cards) offer it, as do some dedicated clones like the ones from MusicQuest, Voyetra and Midiman - or more recent PCMIDI or Orpheus cards developed here on Vogons with a CPU for intelligent mode.

For the latter, pretty much any sound card with bug-free MPU (=non Creative or Mediavision) offers UART mode and can work with SoftMPU. It works with the vast majority of games, but can get stuck where games need extreme amounts of conventional memory or don't work with an EMM memory manager loaded. It's a pretty good (and free) alternative if you don't have intelligent mode MPU in hardware.