Graphic EQ

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Graphic EQ is a graphic equalizer. Equalization is a way of manipulating sounds by Frequency. It allows you to increase the volume of some frequencies and reduce others. This is a more advanced form of the EQ and Tone controls on many audio systems.

As an example of equalization, the curve defined by the slider settings shown below changes the balance of high and low frequencies in the audio, boosting the low frequencies. The default setting is flat with all the sliders set at 0 dB.

Equalization is also available in a "Draw curves" mode, accessed via Effect > Filter Curve EQ
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 clip then Audacity will split the original clip so that the the selection can be rendered as part of applying the effect.
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.
Alert If you apply this effect with an envelope present then there is a bug whereby the envelope is removed and the audio reverts to its full amplitude state prior to the effect being applied.
Accessed by: Effect > EQ and Filters > Graphic EQ
Graphic EQ 3-2-0.png


Contents

  1. Graphic EQ sliders
  2. Equalization settings
  3. Limitations
  4. The buttons


Graphic EQ sliders

Frequency Sliders: the equalization curve is drawn by manipulating a set of sliders. Each slider adjusts the gain of a specific range of frequencies, the gain being maximized at (centered on) the frequency stated on the slider. Click and drag the slider up or down to increase or decrease the volume by a maximum of 20 dB. You can Tab between each slider. You can get to an exact slider value but the method depends to some extent on your operating system. Try:

  • Clicking above or below the slider to increment it up or down by a fixed value in whole dB
  • Clicking above or below the slider to jump to a nearby whole dB value
  • Using the arrow keys on the keyboard to increment by 1 dB
  • Holding down Shift then either dragging the slider handle or using the arrow keys to increment by 0.1 dB.

The sliders can also be made taller by resizing the dialog. This can make setting the value you want easier.

The current value of the slider can be seen by hovering over it with the mouse.

Advice No account is taken of whether your slider settings will result in the selection being amplified beyond the clipping (distortion) level.

If your slider settings amplifies any frequencies, especially the lower frequencies which are normally the loudest, Effect > Normalize the track(s) first to -3 dB or lower. If necessary you can always Edit > Undo the Graphic EQ, Normalize again to a lower level, then re-apply Graphic EQ.


Equalization settings

  • Flatten: A quick way to set a "level response curve". This means the curve on the graph is drawn from left to right at 0 dB on the vertical scale, so that no frequencies will have their volume level modified.
  • Invert: Turns the current curve in the window upside down, changing positive gains at a particular frequency into negative, and vice versa.
Tip Graphic EQ now facilitates the import of pre-existing equalization curves, using the Manage button, for use in the effect.
  • Many published curves, such as those on the Muse website, and curves you may have exported in earlier versions of Audacity with the old Equalization effect, are in .XML format.
  • Graphic EQ, like all other Audacity effects, expects the imports to be text files in .TXT format. To facilitate this we have provided a tool EQ XML to TXT Converter, this is not enabled by default but you can enable it with the Plugin Manager after which it will be present in the Tools Menu.


Limitations

To process Equalization, all tracks in the project must have the same sample rate. To change the sample rate of a track without affecting speed or pitch, use Tracks > Resample.

Links

>  Filter Curve EQ

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