Notch Filter



Notch Filter sharply attenuates frequency-specific noise like mains hum or electrical whistle with minimal damage to the remaining audio, by cutting a "notch" out of the frequency spectrum at that point.
 * Accessed by: Effect > Notch Filter...
 * [[Image:Notch_Filter.png|link=]]

Frequency
Use the slider to choose any frequency up to 10000 Hz (default is 60 Hz). Frequencies above 10000 Hz can be entered by typing in the text box. You cannot enter a frequency greater than half the sample rate of the track, because a track can only contain frequencies up to half its sample rate.

Q factor
This determines the width of the notch cut from your audio (default value is 1). Use the slider to choose a Q factor between 0.1 and 20. Values above 1 create a narrower notch, and values below 1 create a wider notch. Values outside the slider range can be entered by typing in the text box (the Q Factor must be at least 0.01).

The buttons
Clicking on the command buttons give the following results:
 * gives a dropdown menu enabling you to manage presets for the tool and to see some detail about the tool. For details see Manage presets.
 * plays a short preview of what the audio would sound like if the effect is applied with the current settings, without making actual changes to the audio. The length of preview is determined by your setting in, the default setting is 6 seconds.
 * applies the effect to the selected audio with the current effect settings, but unlike the effect runs in debug mode. This is primarily of use when writing or editing Nyquist plug-ins.
 * In addition to the normal plug-in behavior, a "debug window" opens to display error messages, normally the debug window will be empty.
 * applies the effect to the selected audio with the current effect settings.
 * aborts the effect and leaves the audio unchanged.

Links
|< Index of Effects, Generators and Analyzers

|< Effect Menu