This is probably a silly question, but I've always been wondering how to make one of the most typical acid/rave synth sounds. You can hear it, for example, starting at 2:37 in Unix - Overdrive Your Speakers Thanks so much in advance! ++A
If I'm not mistaken that is the sound of a Roland TB-303 bassline synthesizer run through a distortion effect.
It's a quite famous sound and is one of the major elements (some would say the major element) of acid music.
That is the classic Roland TB-303, which recently has been re-imagined by Roland with a modern and improved version named AIRA TB3.
If you don’t want to buy the synth (classic or new) you can always pick a good soft-synth emulator with pre-programmed patches. Just google for “tb-303 vst”.
You’ll also find interesting this video documentary about where it comes from and its history.
Alifer, if "experiment" is too vague from the onset, as a starting point, try changing BOTH cutoff and resonance in realtime. Twist those knobs as the sound (even one repeated note) plays. That frequency modulation (i.e., "sound gets blurrier and sharper") is responsible for the "squelchy"-ness which is integral to acid. Then process the sound through different types of distortion.
There are MANY TB-303 clones out there worth googling, one of my faves is D16's Phoscyon http://www.d16.pl/index.php?menu=10 because it has precise presets with the sound you're looking for, which you can reverse-engineer to your liking.