I am designing a circuit that is intended to capture audio samples from multiple channels for sound source localisation.
Each channel has the following 2 stage op-amp circuit, before going into a 13bit ADC:
I would like to be able to localise sound sources up to about 10KHz but the larger the bandwidth the better (I think the condenser mics can handle up to about 16KHz, not 100% sure)
The faster I sample the better the spatial resolution I can get. I am able to squeeze a sample rate of about 75KHz.
Question Do I need to worry about anti-aliasing filters before the ADC? As I understand it aliasing only occurs when you operate below the Nyquist limit, so a theoretical maximum frequency component of 75KHz/2 would be my limit, which is much higher than I need.
If I don't need any anti-aliasing filters is there anything else I should be doing to remove unwanted noise on the output? When I look on a scope it seems to be OK but this is only with 1 channel built, I am worried when I add all five channels on the same board that they are going to interfere with each other.