Its hard to say exactly, I only make sounds by fiddling about, I dont have enough synthesis knowledge that I can hear a sound or picture it and then make that exact sound without tweaking around for a while - Im getting there slowly - what programmes are you using?

Id start with a fairly thick pad sound, crush it a little bit with bit reduction or some creative distortion or you could try running it through an amp simulator to give it that punchy / crunchy / crackly vibe - you might lose some of the lows / highs though so maybe thicken it up again with some saturation.

Then play around with cutoff and resonance untill you hit the right sort of tone you are after, you might need to automate these to get the squelching to sit how you want it on the attack or release - adjust the release / decay of the sound to give a little more tail and body. You might need to layer a few pads together to achieve the fullness you are after. Then EQ it and add some reverb to get it sitting nicely with your other sounds.

I only use abletons instruments and some plugins so the above is just how I would go about it.

FM Synthesis Bass Tutorial by Moogulator is a good tutorial for operator - I dont know what youre using though?