I am looking for an effect I'd like to add to a track I am working on. What I want is the sound you get (or in films you get) when a walky talk or recording breaks. Where the sound of the voice out of the speakers gets slower and deeper and trails off to nothing.

Alternatively do you have any ideas or similar effects I could use to give a short vocal a sinister, mystery and dying kind of sound?

I suppose an easy way to show what I mean is the way Zam Wessel's voice goes before and as shes dying in this star wars clip: http://www.youtube.com/watch?v=IdSUKIFnYc8

If any of you have an ideas you could share I'd be a very happy and greatful man.

Saturation, ring modulation and pitch shifting downwards.
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