If you're playing older games that use MIDI (DOS and early Windows mostly) without using extra software or an external MIDI device then you'll likely be using the included Microsoft GS that comes with Windows. This is a down sampled version of Roland's Sound Canvas - 55 (SC-55) and is generally considered not as good as a real SC-55.

The interesting thing about MIDI is that Roland's version of a guitar will sound different than Yamaha's which will sound different than another person's soundfont file. This means that a game can have a very different musical feel by changing what software or hardware the MIDI data is sent to.

As GOG often doesn't choose the "best" sound option when configuring their DOSBox game builds, it can be be advantageous to know what one likes.

So yes, the sound "cards" we have today are good enough; but they don't always give us the best sounding option with older software.

*To anyone that's interested in seeing how different a game can sound with different DOSBox configurations, here's a video I found showcasing Space Quest III with different sound options. Note that this game actually predates the General MIDI format so you won't be seeing the SC-55 or other comparable MIDI devices used here, but their predecessor the MT-32 makes a good showing instead.
https://youtu.be/BMmFcs-_4x4?t=230

The discussion here is about General MIDI music in MS-DOS games, around 1993-1996 or so.

With a "motherboard soundcard", by default you are restricted to the "Microsoft GS Wavetable Synth" that comes bundled with Windows. Sure it gives General MIDI sound in those games, but the quality is not that good and it lacks e.g. the advanced Sound Canvas features that many of those "General MIDI" games support.

You can enhance that General MIDI music either by using better General MIDI sound card or external MIDI module/keyboard, or using a replacement software synthesizer like VirtualMIDISynth and use some replacement General MIDI soundfont with it (I prefer Chorium Rev.A soundfont overall).

Then you get vastly better General MIDI music in those older MS-DOS games. So to answer to your question:

Yes, a motherboard soundcard is enough, at least if you install VirtualMIDISynth and a good replacement General MIDI soundfont for it.

Here is an example. This is how General MIDI sounds with the default Microsoft GS Wavetable Synth:

https://www.youtube.com/watch?v=zFGsxoCXmMM#t=1

Here is how it sounds if you replace it with a replacement soundfont, in this case Timbres of Heaven soundfont:

https://www.youtube.com/watch?v=zFGsxoCXmMM#t=44

I see, thx for the explanation

thought the actual hardware sounds better or something, for me using munt emulation looks much easier to implement than buying a module and somehow link it with the pc

Munt is a great option these days and the software emulation is very good. For games written with the MT-32 in mind it gives great sound. For games developed later with General MIDI in mind (games like Doom, Descent, Duke Nukem 3D, ROTT, Lands of Lore 2, Sam & Max Hit the Road (To name a few)) you'll likely enjoy the soundtrack more with a General MIDI option.

This includes using different Soundfonts through a software solution like VirtualMIDISynth or Falcosoft Midi Player (Harder to set up, but much more versatile as it can also use VSTi's). Or using VSTi's like Sound Canvas VA or Yamaha S-YXG50 (Falcosoft Midi Player also comes with a Munt VSTi). Or of course the hardware devices from which this thread got it's title.

Soundfonts are a great free option and it's pretty easy to get started using VirtualMIDISynth in conjunction with the Coolsoft MIDI Mapper (Allows you to set the default MIDI device in Windows so that your MIDI using games will actually use something besides the default Windows "Microsoft GS Wavetable Synth")

Some popular Soundfonts include the previously named in this thread "Chorium Rev.A" or the aptly named "Fatboy" (Over 300 MB in size)

Why do people use Siri?

A Speak and Spell does the job too

what is siri? and what is speak and spell?

you must be joking...

i had to look them up , an apple crap and and an old game
who the hell uses apple things anyway

Not necessarily. If you compare the consumer-level MIDI synthesizers (sound cards) from e.g. the 90s to the software synthesizer soundfonts of today, the current soundfonts are much bigger, hence can sound much clearer and better than on the old hardware synthesizers.

Roland SCC-1/SC-55 was considered as a high-quality choice for General MIDI game music back in the 90s, and I think its ROM (soundfont) size was a few megabytes in size (I don't recall exactly how big, and the Wikipedia article didn't say), while the current General MIDI soundfonts that you can load with a software synthesizer can be e.g. 30 megabytes in size, or even 300 megabytes (like Timbres of Heaven).

I used to have a Roland SCC-1 sound card and while it did sound very good in old MS-DOS games, I feel a software synth with e.g. Chorium RevA or Timbres of Heaven soundfont does sound better.

Munt (Roland MT-32/CM-32L/LAPC-1) and General MIDI are different things, different kind of MIDI music.

You shouldn't try to compare them directly by playing the same MIDI files on both because a MIDI file made for Roland MT-32 is probably played wrong on a General MIDI device or software synthesizer, and vice versa. The instruments are in a different order (so you get wrong instruments played quite often), different polyphony etc.

So if you play a MS-DOS game and have selected Roland MT-32/CM-32L/LAPC-1 as the music device, then you should use Munt, not a General MIDI device.

If you have selected General MIDI (sometimes called "MPU-401" or "Sound Canvas"), then you shouldn't use Munt but a General MIDI synthesizer/sound font (the default Windows "Microsoft GS Wavetable Synthesizer" will do, but as said its quality is not that good).