Hello i am having trouble for this following circuit. (Top circuit in diagram1) The problem i am having is finding how to calculate the cutoff frequencies for the highpass filter and lowpass filter. This is since i am not sure on what equivalent resistance to use for each formula for each filter (fc=1/(2piRC)). For the highpass i just did that R9 was in series with R8 and then in parallel with R7, then in series with R6 to find that eq resistance so:
However i am not sure if this is correct for one but also i am not sure i can just ignore C6
Although for the lowpass filter i am unsure as how to find the equivalent resistance for the cutoff frequency for the lowpass filter?
Note: I understand i can just place a buffer between it so interaction does not occur between them but i want to know how to calculate it doing it this way
As you can see when V is probed on the bottom half of circuit diagram 1 when using my equivalent resistance for the high pass filter i get what the cutoff frequency is. Note i have tried different resistor values an i always get it matching (for the example below the circuit values used are below this diagram in the bottom circuit)