Please help me understand this circuit.

[braintree]

Hi, first time caller

I've just built this circuit and it sounds really cool. It's designed by the original drummer of Split Enz.

It's got a weird spitting frying pan sound.

As a naive guess I think it looks like the first op amp drives a signal into that diode ladder. Then something like, the higher the signal voltage the more of it passes thru the "gate" of more distant diodes. Like a kind of staggered set of sluice gates.
As to how the signal is mixed together again on through that outgoing op amp, I'm confused.

I'll run a signal into it and poke around with my oscilloscope.

[braintree]

this is how it sounds