Saving applied effects

I am a little unclear regarding how audacity applies and save effects. For example I just did some equalization adjustments on an aup file but did not save them. When I started audacity again I note that the equalizer settings were preserved. So the question is: Despite the fact I didn’t save the file are the equalization s permanently saved? OR-- are they just applied post facto to the aup segments each time I start?


All the EQ data is saved in Audacity’s folder for application data.

The curve points are saved in EQCurves.xml in that folder. The EQ settings (which curve you are currently using, filter length, if you have turned off grids and so on) is stored in the audacity.cfg settings file in that folder.


Thanks. So-are you implying that the change is not permanent–if I set the equalizer back to “flat” it will undo the change?


Perhaps it would help if you explained what you are trying to do. Equalization applies the curve you see in the dialogue to the audio when you press OK.

If you flatten the “unnamed” curve then apply that to audio it will make no change to the audio, but that modification to the “unnamed” curve will be stored in EQCurves.xml and so next time you open Equalization you will see a flattened curve.

If you save a project, there are no EQ settings specific to that project. Equalization opens at its last used settings whether you save a project or not. But Equalization effects you applied to that project’s audio are preserved, whatever your current EQ settings happen to be.


Sorry for not being clear here.

I am trying to apply some equalizing to a project file. I may want to set it back to no-equalizing (flat) then try another group of settings. When I am finished I may not want to keep anything. When I import my wav file I use the “make copy…” option. Audacity can work in one of two ways but I am not sure which it is doing:

1 --If I set the equalizers audacity could apply the transform to a copy of the original project. If I then set the equalizers differently audacity can copy back the original project and apply the new values. Thus if I apply a flat zero EQ the original file is redeemed unchanged. (This is how I would hope it would work-I can then test various EQ attempts)
2-- If I set the equalizers audacity can apply the transform to the copy as above but then if I apply a new set of equalizers I applies them to the already equalized file, compounding the process. Not sure of what value this would be.

Finally when I cancel the session without saving I would hope that the project is not affected. I understand that the EQ settings might be preserved for the program (not the project) but I would think that if I set them to flat/zero when I re-read the project it would render the original.

My concern here is that it seems as though my project retains my test EQ settings even though I didnt save it and I could not get back the original.

First off, the stored EQ settings and whatever EQ’s you apply to the audio are completely unrelated.

That has nothing to do with whether your EQ settings are saved or whether changes you make to the audio are saved.

If “Make a copy” is chosen then Audacity makes a complete copy of the data from the file when first importing the file.

If “Read Directly” is chosen, then when a waveform section is edited, data for that section only is copied in.

As I said, flattening the EQ and applying that flat EQ to the audio leaves the audio unchanged. It does not undo previous EQ changes. If you want to undo EQ, use Edit > Undo Equalization.

If you want to experiment with different EQ’s, you can save a project then Edit > Duplicate the tracks. Apply one EQ experiment to one of the tracks and other experiments to the other tracks. Solo one track only to hear that track only. If you choose Edit > Preferences… then the Tracks section, you can choose the “Simple” option for “Solo” button. This means that only one track can be soloed at a time, so you can then just press “Solo” on the track you want to hear.

Alternatively you can save a separate project for each attempt at Equalization. If you do that, each project starts out containing the file as you imported it. If you make EQ changes but don’t like them, then you can close the project without saving changes. When you open the project again, the file remains as you originally imported it, without EQ changes.

If you choose not to Undo the previous EQ, that is exactly what happens.

Note that you can press Preview in Equalization without committing the changes to disk. Hopefully in the next release or two of Audacity, you will be able to tweak the controls while listening to the effect, before committing the change to disk.

Both those statements are correct.

Wrong - see above.


Thanks Gale. I had some more time to play with this and I see what is going on now. As you mention the EQ parameters are applied against the same copy of the project so successive applications are compounded. I work with large orchestral works so re-establishing or making multiple copies is cumbersome and slow on my laptop. At any rate I would have expected that the various Effects worked as a mask, applying to the a fresh copy each time but it does not work this way. I will just keep a few multiple copies around when working on a project. Fortunately I do not do much “effects” type editing for our orchestra.


If this was a concern for what I was doing, I would simply import the same file twice into the project and keep the duplicate track unchanged.

Also, the duplicate unchanged track can be useful as a way to mix EQ changes in with the original EQ. Use the -…+ gain sliders on each track to determine how much of the “wet” EQ change and “dry” original EQ goes into the mix.