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I'm trying to understand how the AC50CPH Presence control operates. This is my best shot, can you guys take a look and let me know where I'm going wrong?
I had to re-draw it to better understand it:
The Volume pot is a standard volume control.
I don't understand how C6 and R4 can do anything because they are bypassed by the yellow diagonal wire. The setting of the Presence pot does not change the bypass situation. Perhaps the schematic is wrong?
Turning the Presence pot down to minimum, counter-clockwise, (see below) bypasses all pot resistance. R7 + C7 form an RC low pass filter with a cutoff frequency of 605Hz. Only frequencies below 605Hz pass out of the volume pot. R63 acts as an attenuator to limit the max signal out of the volume pot.
Turning the Presence pot up to maximum, clockwise, (see below) adds resistance to the top of C7, reducing the effectiveness of the low pass filter which adds high frequencies back into the mix.
I had to re-draw it to better understand it:
The Volume pot is a standard volume control.
I don't understand how C6 and R4 can do anything because they are bypassed by the yellow diagonal wire. The setting of the Presence pot does not change the bypass situation. Perhaps the schematic is wrong?
Turning the Presence pot down to minimum, counter-clockwise, (see below) bypasses all pot resistance. R7 + C7 form an RC low pass filter with a cutoff frequency of 605Hz. Only frequencies below 605Hz pass out of the volume pot. R63 acts as an attenuator to limit the max signal out of the volume pot.
Turning the Presence pot up to maximum, clockwise, (see below) adds resistance to the top of C7, reducing the effectiveness of the low pass filter which adds high frequencies back into the mix.
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