I always use Audacity to record my music and in order to give my vocals a nicer sound, I always use the Treble Boost preset of the Equalizer. This afternoon, I was recording, using it as always, when suddenly, out of the blue, the Equalizer didn’t work anymore and showed a straight line, without any curves. This turned out to be the case with all presets(Walkie Talkie, Treble Cut, etc.), not just Treble Boost, rendering them all useless.
Now, the question is of course: how do I get them back? And what went wrong? As far as I know, I didn’t do anything different or clicked anywhere I shouldn’t have.
EQ curves have not been built into Audacity for many years now. They depend on an external file, the last fallback for which is EQDefaultCurves.xml which ships with Audacity in its installation folder. When you use Equalization, the curves you have and their settings are copied to Audacity’s folder for application data as EQCurves.xml.
It looks like you may have a corrupted file, given you have the curve names in the dropdown in Equalization.
Using 2.0.2 you can right-click this link: Audacity default curves, save it to your computer and put it in Audacity’s installation folder. The curves in that link are the current Audacity curves, not whatever was shipped with 2.0.2.
Then go to Audacity’s folder for application data, in your case Users<your username>\AppData\Roaming\Audacity\ , and rename EQCurves.xml and your EQBackup.xml (for example, remove the first “E” in the name). Then Audacity should read the installed EQDefaultCurves.xml and copy it to its folder for application data as EQCurves.xml.
If that doesn’t help you’ll have to install 2.1.2 from http://www.audacityteam.org/download/windows which will install the curve file linked to above. I suggest you enable the option to Reset Preferences half way through the installation, although that doesn’t directly affect Equalization. If you have no reason to use the old 2.0.2 version, you could just do that anyway. You will still need to rename the old EQ curves in Users<your username>\AppData\Roaming\Audacity\ .
That solved the symptom. Nobody knows why the original file vanished. That’s concerning. Operating files don’t just vanish. Is your virus software up to date? Isn’t there a Windows drive health check you can do?
If there was no EQ*.xml file in Audacity’s application data folder or the installation folder, there would be no curves to choose from. As I said, the problem seemed to be that whichever EQ file was being read, it was corrupt, rendering the curves as flat lines. I vaguely recall corruption bugs in Equalization around that time, but that is a problem with running an old version of Audacity.