Synth used at the very beginning (and throughout) of Corc?

Does anyone know or have a good idea of what synthesizer is being used at the beginning and thought of the track Corc? It's the first one you hear.

My guess would be Nord Modular. It sounds to me like audio-rate modulation of filter cutoff. You can approximate this in most modular software like Reaktor, Max, PD, etc. It's probably layered with something a little subtler to give it some more body.