Spectral Edit Multi Tool

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The Spectral Edit Multi Tool is used with a Spectral Selection to apply either a notch filter, high-pass filter or low-pass filter to the selection, depending on the type of selection made.
Advice Note carefully that when you apply an effect to a time-stretched clip the changed speed of the clip will be automatically rendered.
  • If you apply an effect to a selection within a time-stretched clip then Audacity will split the original clip so that the selection can be rendered as part of applying the effect.
Accessed by: Effect > Spectral Tools > Spectral Edit Multi Tool

Depending on how the track is displayed and what spectral selection has been made, this effect will do one of the following:

  • When the track is not in a Spectrogram View with Spectral Selection enabled, an error message will be displayed
  • When the spectral selection has a center, upper and lower frequency this effect performs as a notch filter with the center frequency defined by the center frequency of the spectral selection and the width defined by the upper and lower frequencies of the spectral selection
  • When the spectral selection begins at 0 Hz this effect performs a high pass filter with a roll-off of 12 dB/octave and with the cutoff frequency defined by the upper frequency of the spectral selection
  • When the spectral selection ends at the Nyquist frequency of the track this effect performs a low pass filter with a roll-off of 12 dB/octave and with the cutoff frequency defined by the lower frequency of the spectral selection
  • When both the upper and lower frequency bound of the spectral selection are undefined, an error message will be displayed. You should go back and define one or both frequency bounds.
Tip If the attenuation is not sufficient, you can use Ctrl + R to repeat the effect.

Examples

Notch Filter

If you make a spectral selection that has both an upper and lower boundary, selecting Effect > Spectral Edit Multi Tool will apply a notch filter.

In the following example the spectral selection had a center frequency of 2,000 Hz and a bandwidth of 0.5 octave.

SpectralEditNotch.png

In the following example the spectral selection had a center frequency of 2,000 Hz and a bandwidth of 2 octaves.

SpectralEditNotch02.png

High-pass filter

If you make a spectral selection that has the lower boundary at 0 Hz, selecting Effect > Spectral Edit Multi Tool will apply a high-pass filter.

In the following example the spectral selection had a lower boundary of 0 Hz and an upper boundary of 500 Hz.

SpectralEditMultiHP500.png

Low-pass filter

If you make a spectral selection that has the upper boundary at the Nyquist frequency of the track, selecting Effect > Spectral Edit Multi Tool will apply a low-pass filter.

In the following example the spectral selection had a lower boundary of 0 Hz and an upper boundary of 2,000 Hz.

SpectralEditMultiLP2000.png