Very late reply but i'd like to know this except the opposite. From watching gameplay i can tell that the game can use a different sound device other than MIDI. I'd like to change it from MIDI to the CD quality like one.

EDIT
Solved the problem by renaming the DAT file to ISO, mounting it and loading the game up in Scummvm.


Search for the Scummvm thread on this forum.

This works for other GOG DOSBox games too in Windows 7 (assuming below that you installed the game in the default place on C: drive):

1. Locate the game shortcut in the Start Menu (in this case "I Have No Mouth..." under Start => All Programs => I Have No Mouth..., and right click on it. Not sure how to do this in Windows 8, you have to locate the shortcut from the depths of your hard drive instead.

2. Select Properties.

3. In the target box, remove "-c exit" from the end of the command string, so that it would look something like this:

"C:\GOG Games\I Have No Mouth, and I Must Scream\DOSBOX\DOSBox.exe" -conf "..\dosboxnomouth.conf" -conf "..\dosboxnomouth_single.conf" -noconsole

4. Click OK.

5. Locate C:\GOG Games\I Have No Mouth, and I Must Scream\dosboxnomouth_single.conf, and edit it with Notepad. If the file is unreadable in Notepad (missing linefeeds), open it in Wordpad instead, save it (Ctrl-S), exit Wordpad, and open it again in Notepad.

6. Comment out the two lines (where the game is run and exit) with #. Also, I think it is a good idea at this point to put some kind of mixer volume setting to that conf file so that the Soundblaster sound effect (like speech) won't be so loud compared to the MIDI music.

So the conf file should look something like this: The bolded lines were edited or added.

7. Save the conf file, and rerun the game from the Start menu shortcut. Now you should end up in the DOSBox prompt inside the game directory, and you can run install.exe

8. In the game installer, select:

Configure Sound & Music Drivers
Select and configure MIDI music driver
General MIDI (Roland MPU-401 interface or 100% compatible)
Attempt to configure sound driver automatically
OK
Done
Quit Installation

9. Then you can run the game by running SCREAM.BAT. When you are done with the game, if you end up in this same DOSBox prompt, write "exit" to exit the DOSBox session.

If you want, you can change the dosboxnomouth_single.conf by removing the # from the "scream" and "exit" lines, and adding "-c exit" at the end of the Start menu shortcut target. But you can just as well leave it like it is now, you just need to start the game with SCREAM.BAT in the DOSBox session, and give EXIT after the game.

Can you tell more about this? I loaded the game in ScummVM, and it seemed to have pretty basic General MIDI music only (poorer than what I get with the GOG/DOSBox version, when I am using Chorium Rev A General MIDI soundfont).

Or do you have to have the ISO mounted in Windows while you play the ScummVM version, in order to hear CD music? Should you be able to listen to the CD music tracks if you just load the mounted ISO into a media player, as an audio CD?

EDIT: Maybe I misunderstood, you, because I think now the game has only MIDI music (no CD music) because even the extra soundtrack you get with the GOG versions sounds merely like General MIDI, only with a good GM unit or soundfont.
I have the original IHNMAIMS retail CD version too so I guess I could check whether it has CD music, but I don't believe so.

So to make the GOG version sound (close to) as good as the music sounds in those GOG soundtrack files:

1. Change the music output of the game to General MIDI, according to the instructions in my earlier reply.

2. Install BASSMIDI to Windows, and also download a replacement General MIDI soundfont (I recommend Chorium Rev A, google for it, it sounds great also with this game) which you use with BASSMIDI. This makes the General MIDI sound better than with the default Microsoft GS Wavetable Synth that Windows comes with.

In fact, when I ran the game through ScummVM 1.6.0, I think it the music sounded worse than the GOG version with the aforementioned steps. I think it was only using MS GS Wavetable Synth for the MIDI music, ignoring BASSMIDI and the replacement soundfont.