I'm interested in implemented a "layered" sampler in csound, for use 
with piano samples. My question has to do with interpolation between layers.

Recently I purchased the piano engine "Ivory," and kinda regret it. I 
wish I had purchased Gigastudio and a good set of piano samples instead, 
because Giga is fully programmable and configurable. Anyway, it occurred 
to me that I can easily "extract" the samples, at all layers, from Ivory 
simply by having it play one note at a time. (I can automate this, of 
course.) Then I can implement a layered sampler in Csound.

So regarding interpolation between layers, is there anything complex to 
this, or is it simply  Layer1_signal*R + Layer2_signal*(1-R) ?

I'm wondering if the samples have to be "phase coherent" (not sure what 
I'm talking about here) to avoid peaks and nulls. If so, they probably 
will already be that way when I extract them from Ivory.

Thanks,
Mike