Audio Post 4: Filters

Posted by bsteel on
Monday, March 3rd, 2008 at 3:04 am

A filter is a type of equalizer that sharply attenuates frequencies above or below a certain frequency. Filters are used to remove noise, undesirable frequencies and bleed from other sounds/instruments above or below a specified frequency range. There are two types of filters that will be most beneficial to our project the high-pass and the low-pass filter.

High-Pass Filter passes audio signal above a chosen frequency and attenuates audio signal below that specified frequency. Thus, a high-pass filter set at 50 Hz would cut all audio frequencies below 50 Hz and pass all frequencies above 50 Hz.

Low-Pass Filter is exactly the opposite of a high-pass filter. The low-pass filter passes audio signal below a chosen frequency and attenuates all audio signal above the specified frequency. Thus, a low-pass filter set at 5 kHz will pass all audio signal below 5 kHz and attenuate all audio signal above 5 kHz.

-Brian Steel, Director, Spielberg Group