Today's Lesson

A low pass filter, often abbreviated LPF, allows the signal below a selected frequency to pass through unaffected while removing the signal above that frequency, which are the high frequency sounds. On a TouchMix and some other mixers this same function is referred to as “high cut.”

On the EQ page of a TouchMix, select the “high cut” icon. Select the frequency knob below so that it is highlight yellow and use the toggle wheel to adjust the low pass filter to the desired frequency for your application.

On an input channel a low pass filter is useful in filtering out unwanted high frequency content from a signal; for example cutting out some of the piercing high tones of a flute or cutting out the shrill sound of a violin bow passing over the strings.

Low pass filters are also used on aux fed subwoofers to help create a tight, punchy bass sound.

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