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Tone control through feedback network

I'm looking at this schematic and I wonder how the bass and highs are boosted through a passive network. When input and output are out of phase the feedback would cancel, so far the obvious. But for a boost the phase should be reversed, not?
 

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no...the phase is reversed for both boost and cut...you just vary through the means of a potentiometer the percentage ofthe signal that cancel. You have here the asc file for such a network.Try to modify the ratio of r14/r15 highs) and r19/1(i made amistake modifying the name of that resistor to its value at some point):
DON'T ASK phono and headphones amplifier with equalization
The linear response is in when an antilog potentiometer(5kohm/45kohm for a total of 50kohm) is half way.