The main use of filters in audio products is to modify the frequency content of an audio signal. There are various ways that a filter can remove (or enhance) the frequencies of a signal and in general there are a few key responses.
- Lowpass Filter:
Lowpass filters only allow frequencies below a certain threshold to pass through, frequencies above this threshold are reduced in amplitude or completely silenced. In other words, a lowpass filter removes high frequencies from a signal.
- Highpass Filter
Highpass filters only allow frequencies above a certain threshold to pass through, frequencies below this threshold are reduced in amplitude or completely silenced. In other words, a highpass filter removes low frequencies from a signal