Old School DOS games

[Treewyrm]

Btw it's quite hard to find the correctly played muscis from doom on YT.

There's no 'correctly played' music (unless we're talking about notorious hanging note bug in certain SoundBlaster models). It's MIDI (GM) so how it sounds depends on synthesizer and they all are slightly different to each other having their own signature sound. Doom music was made on Roland SC-55 if you want it sort of 'authentic'. Personally I prefer SC-88 instead, someone else might prefer Yamaha MU80 or something and that's what good about old school MIDI - everyone can tailor it to their own tastes or even turn them into chiptunes should they want to.