[SpookyZalost]

SO I'm working on a more detailed explanation...

but I was incorrect with this last post and had to spend time studying and relearning stuff.

first, the circuit listed here is a low pass filter, an active one.



This is the Audio Amplification chip, each side connects to a low pass filter, both the same frequency and are mirrored and connect to each input (L channel, R channel).



now here's what it does.



First the sound comes in (red line), it goes through the filter circuit (blue line) which set's the filter frequency via the capacitors, this works by filtering out all but the specific frequency based on the capacitance of the circuit.

finally it goes both to the amp and ground using the resistors to filter out any excess noise leaving a clean signal at that specific frequency, amplified to prevent a decrease in voltage from the filtering.

this then goes back through the filter in a loop with the input/output going through the same wire to the potentiometer (slider control), on the front of the equalizer.

this circuit is mirrored for each operational amplifier chip and each side services either the left or right audio channel before being mixed back and pushed out through another circuit I'm still working on decoding.

each filter circuit has different capacitors at different ratings to change the frequency, the resistors are the same though.

here's the schematic I came up with, I wrote down the numbers that were the same and left blank the capacitors because they vary depending on frequency.



the capacitors are the same in the rest of the filter loop, the first two are replaced by a single capacitor however, not sure why this first one is in parallel, the rest is the same though.

Change value to match, this circuit filters out all but 60hz frequency and the potentiometer changes the volume of that frequency.

as a side note, the hertz calculations are factored in with the following.



we know the values of R and C.

R=220kohms
C=12nF (nano farads)
F=60hz

meaning C4 and R2 are the frequency filter.

this leaves the op amp, C3 and R3 as the filtered amplification circuit
and C1 and C2 as some kind of feedback noise reducing circuit, as determined by their polarity, only certain frequencies can get through.