Fishman PRO-EQ PLATINUM User Manual page 8

Notch and Phase
These controls work to suppress two
adjacent ranges of acoustic feedback. We
use guitar as an example, but the Notch
fi lter and Phase switch are compatible with
all acoustic instruments.
The Notch control is a variable
frequency notch fi lter designed to subdue
a resonant peak on the instrument which
is prone to feedback. Turning the knob
adjusts the center frequency of the fi lter,
ranging from subsonic (off) to 330Hz at full
clockwise.
Lower Feedback Range
(E to G#)
Upper Feedback Range
(A and above)
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