Phaser update

[Jeroen Proveniers]

Last night was a frustating one -:)

I got the haircomb response, but in no way I could make those poles move, I
can only move them closer, which does not give phaser at all, everything
ends into vibrato or phaser. So, I'll move to the allpass filters, although
I don't really know how to calculate them.

And all this started as a quick thing, "we can fix that in half an hour like
the chorus". Nope.. but now I must get it right.

JJ