How to get a specific sound?

I’m trying to work out how to get what I would describe as the burbling filter sweep at 2.40 in the below video from my mother 32? Any ideas or do I need more oscillators eg 3 as per the mini Moog?


https://www.youtube.com/watch?v=Yz2O_hy6zP0

I hear only one voice, with a very fast tempo, which goes through an envelope (or manual sweep) of the filter with resonance turned up to self resonate.

If I actually had the time to copy that on my GM, I would sequence with one OSC.

Thanks I’ll try again