The global feedback signal, usable for phase modulation and within the Shapers, is defined by a mix of four signals provided by the two filters and the Effects section (blendable between pre and post Reverb). Each signal is weighted by a bipolar Amount parameter, as the polarity can have a noticeable influence on the feedback behavior.
A sine shaper (providing Drive, Fold and Asymmetry, as described for the branch Shapers) can manipulate the sum signal and create additional harmonics. The sum also can be amplified or damped by a Level parameter that can be sensitive to Key Tracking.
The feedback signal will be a mixture of polyphonic signals (provided by the filters) and monophonic signals (provided by the effects, having no more voice association and being a downmix of the original stereo signal).