Hey. thanks! I suggest small value pots. 100 ohms primarily. If you can find 200ohm pots I would use those as well. 500 ohms may be too much. I've found that most glitches have a sweet spot sweep of around 20 ohms. Its a bit odd but a lot of the glitches will have a window where they change... so for instance between 0 and 20 ohms it will crash, between 20-40 ohms it will glitch and the glitch will change as you increase the resistance. Above 40 ohms and the glitch turns off. That's just an example, you'll find lots of different scenarios.