Mid stage:
This is a mid frequency cut/boost filter.
C14 is a decoupling cap.
The formula to get the cut off frequency is:
Assuming R13 = R15 and R14=R16
F=(1 / 2 x pi) x Sqrt((2 x R13 + MID1)/(R13 x MID1 x C16 x C17 x (R13 + R14)))
Giving us F=760Hz for the filter center frequency.
The max attenuation/boost at 760Hz is given by:
Gboost= ((R14 x ( R13 + Mid1))/(R14 + R13+ Mid1))/((R14 x R13)/(R14 + R13))
Gcut= 1/Gboost
Giving us:
Gboost=9,1 or 19,2dB
Gcut=0,1099 or -19,2dB
Low cut stage:
This a simple RC low pass filter to smooth the distortion.
Frequency cut ranges from 1/(2xPIx(R11+TREBLE1)xC13) =312Hz to 15915kHz.
Copyright Zorg Effects G.Denneulin december 2015 – For non commercial use only.
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