Completed Proposal Import/Export Eq Curves

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Proposal pages help us get from feature requests into actual plans. This page is a proposal for automatically removing DC bias.
Proposal pages are used on an ongoing basis by the Audacity development team and are open to edits from visitors to the wiki. They are a good way to get community feedback on a proposal.

  • Note: Proposals for Google Summer of Code projects are significantly different in structure, are submitted via Google's web app and may or may not have a corresponding proposal page.

Proposed Feature

To provide a simple method to import/export curves for the Equalizer effect. This would allow a "library" of curves to be made available for simple download and installation by any user.

Developer Backing

  • Martyn Shaw?

Use Cases

  • The Equalizer effect is a versatile multi-purpose tool used by most users:
  • The current Preset list is dominated by "vinyl equalization" curves.
  • Many other curves that would be useful to many users are excluded.
  • What may be a useful set of curves for some users will be irrelevant to other users. A simple method to import "preset" curves will allow users to load the Equalizer effect with the curves that are most useful for them.
  • A simple method to export curves will allow users to easily share their custom curves with others and quickly build a library of Equalizer settings.


It has occurred many times on the forum that a user has asked how to achieve a result using the Equalizer, for example how to simulate the sound of a walkie-talkie, or remove the harshness from a vocal recording. While it is simple to produce suitable Eq settings, passing that information on to the user either requires that they try to copy a screen-capture or manually edit the EQCurves.xml file. Neither of these solutions are convenient or user friendly.

There has recently been a revised RIAA curve produced. The facility for easily importing curves would allow users to immediately make use of this and similar resources.

A selection of "general purpose" settings such as "bass boost/bass cut/treble boost/treble cut/telephone/loudness/rumble filter" would not only be useful to a wide audience but could have "educational value" for people that are new to audio processing.


From a user perspective, a simple way to implement import/export of Eq curves would be the addition of 2 buttons on the Equalizer interface. Clicking the "Export" button would bring up a browser window allowing the current curve settings to be exported as an XML file. Clicking the "Import" button would bring up a browser window allowing a correctly formatted XML file to be imported and becoming the current Custom curve.

The name of the curve could be included in the XML file but this poses potential issues of duplicate curve names. Alternatively the curve could unnamed and simply become the "Custom" curve that the user can Save into their preset list in the normal way.

Position of the buttons:

There are various options but at present I would favour placing the Import/Export buttons after the Save/Delete buttons. The "Grid" checkbox could be moved lower down to the same line as "Preview" button.