General MIDI vs MT-32

[ZvikaZ]

Hi.
I've read a long time ago, and I don't remember where, that first SCI games were composed with a MT-32 (and therefore sound best with a MT-32, or Munt), while later SCI games were composed with a SC-55 (and therefore sound best with General MIDI).


1.
Is it accurate?

2.
When was this transform from MT-32 to SC-55 done?
In other words, I want to know which games are better sounded with MT-32, and which games are better sounded with GM.

Thanks

[Kawa]

My observations regarding the MT-32:

• The first few SCI 0 games had no special patches to reprogram the MT-32. Means they load pretty quick.
• Then they started using game-specific patches. This is the set of games with cute startup messages like "INSERT BUCKAZOID".
• The later SCI games, starting with 1.1, shared a common MT-32 patch resource, with "SIERRA ON-LINE" as the single message. This patch approximates the General MIDI standard.

To answer your questions then, I don't know if it's accurate but if it is, the switch would likely be when they started using that single patch in SCI 1.1 and later.

[ZvikaZ]

My observations regarding the MT-32:

• The first few SCI 0 games had no special patches to reprogram the MT-32. Means they load pretty quick.
• Then they started using game-specific patches. This is the set of games with cute startup messages like "INSERT BUCKAZOID".
• The later SCI games, starting with 1.1, shared a common MT-32 patch resource, with "SIERRA ON-LINE" as the single message. This patch approximates the General MIDI standard.

To answer your questions then, I don't know if it's accurate but if it is, the switch would likely be when they started using that single patch in SCI 1.1 and later.

Thanks, it makes sense.
I've looked at the games that are SCI 1.1, and before SCI 1.1 (at https://wiki.scummvm.org/index.php?title=Sierra_Game_Versions#SCI1.1) and was surprised to see that SQ4 (floppy) is SCI1 (early), while SQ4 (CD) is SCI1.1
It's interesting to compare them - do they use the same sound resources? (and then SQ4 is probably an exception to our MT32/GM rule), or maybe Sierra have re-composed the sound tracks? if so - why should they do such an effort?

[Kawa]

SQ4 CD uses the same MT-32 patch as the diskette version, so it's safe to say the music was unaltered (besides possibly any trademark infringement fixes).

In fact, another thing you can tell the custom and shared patches apart from is a tiny detail in their formats: the custom patches have their LCD messages stored up front in a block of their own, so if you look at them in a hex viewer you see the starting message "   SPACE QUEST IV   ", finishing message "Calling Roger Wilco ", and shutdown message "SequelPoliceRWatching" right there at the start. If you look at the shared patch, that entire block is missing -- the "   Sierra On-Line   " message is sent as part of the big MIDI SysEx block that does the actual reprogramming.

Going by the list you linked, in its order: PQ1, QfG1 Demo, MuMG have old-style patches with the cutesy messages. QfG3, Brain2, and KQ6 have the shared patch. SQ4 CD and Eco1 CD then drop back to using the old patch. Eco2 jumps back to the shared patch, SQ5 has a new style patch too but it's missing the message.

It seems clear then that the SCI 1.1 updates of SCI 1.0 games retain their old patches. IIRC the support for the three messages at the start of the patch file is up to the driver file so that could make it very easy...

[MusicallyInspired]

Pretty much every game using SCI1.1 and up was composed for General MIDI (SC-55 particularly) with MT-32 support added as an afterthought with a General MIDI-esque patch map. There are only a small few exceptions to this. Two being:

• Police Quest 1 VGA
• Laura Bow 2

Those are the only two I ever remember offhand that were composed for the MT-32 and General MIDI was added later and the game itself was released in SCI1.1 (may have started out life as SCI1.0 games). If there are more there aren't many. SC-55 quickly took over and MT-32 was left in the dust, to sometimes less than appealing results.

SQ4CD has the same sound files from SQ4 floppy. It uses a special driver that remaps the MT-32 instruments to General MIDI on the fly (and it doesn't do a very good job as many instruments are missing, including drum kits).

KQ5CD is interesting in that it's SCI1.0, but it has a Windows interpreter which means it must also support General MIDI (specifically Extended and Base MIDI). As such, every sound file numbered 1000 and up are GM Ext/Base MIDI duplicates of the MT-32 sounds numbered under 1000. (incidentally, SQ4CD also does this for its Windows version)

SQ5 was made by Dynamix who used their own General MIDI MT-32 patch map with slightly better results than Sierra's.

Eco Quest 1 was released on both SCI1.0 and SCI1.1. The SCI1.0 version obviously supports only MT-32 (logically) so that's what it was composed for.

QFG1VGA uses the MT-32 sound files from the original game but also had new music written for it that's not in the EGA original. I'm unsure at the moment if these pieces were composed with the MT-32 or General MIDI. My guess is the latter.

That's all the edge cases I can think of right now. Basically, if it started life as an SCI1.0 game then it was composed for the MT-32. This is mostly obvious except in PQ1VGA's and LB2's cases.

Also, it may interest some here that on the Space Quest Historian Discord server we've started a community Google spreadsheet to chart every MIDI sound file in all the SCI games. The purpose being to identify which sound resources are which themes to make it easier to pick out the themes you're looking for easier. It's a community spreadsheet which means anyone can help go through the resources with SCI Viewer or Companion, listen to each resource, and mark down the song titles for each game. For bonus points, you can search the decompiled game scripts to find which scripts trigger each sound file. We've got a few games completed already for reference. You can also see in SQ4CD and KQ5CD's cases where the Windows duplicate sound resources start. It also lists for each game which device it was composed with/sounds best on.

https://docs.google.com/spreadsheets/d/1ECMTncmqfG__6lY5v5v1JhkviC8pxW_v0sX_ILwS-ZI/edit?usp=sharing