I am currently taking a class on filter design, and I am learning by doing.
I want to make a small project by building a microphone circuit.
I found online a tutorial by Great Scott. He made a circuit like this. His results were pretty good so I will probably leave it as it is. His design already has a low and high pass filter implemented in the design building a bandpass filter.
I am thinking also about implementing an active high pass filter on the end of the circuit to cancel out low frequency noise and get better signal quality and also practice the real world application of what we do in the lecture. I used the Texas Instruments filter design tool to create a 3rd order Bessel filter, with 3dB gain because its voltage peaks were around 3V. I think it would be better if they were closer to 5V, I was thinking a little less than 4.5V.
Now my problem is that I have no idea how to choose the cutoff frequency. I was thinking 60Hz would be induced from AC wires around the house etc. So triple that at 180Hz should be good - I guess. I would appreciate any input and help on the matter.