Hack Audio: Low-Pass Filter

A basic type of spectral effect is the low-pass filter (LPF). This effect reduces the amplitude of high frequencies while letting the low frequencies pass through without being attenuated. One approach to creating this effect is to use parallel processing with delay. In MATLAB, the impulse response of the effect can be analyzed using the function: "freqz". It creates a plot of the frequency response of the effect. Check out http://www.hackaudio.com/ for more information.