Dear friends, I have a funny problem. I am using Audacity 2.1.3 on Windows 10 since more or less a week. A couple of days ago I imported an audio file on Audacity to work on its equalization. So, I went on effect → equalization, and Audacity showed me the graphic wave of my file. Then, I started to work and at some point I selected the “flatten” button. Unsatisfied with my work, I tried to go back to the original graphic wave, but I couldn’t manage to do so: even re-importing the file or importing other files, when I select “equalization” Audacity doesn’t show me the graphic form of the file, but automatically a flattened one! I checked out the guide but it doesn’t say anything about that. I even tried to reinstall Audacity, but it didn’t work. I know I’m probably missing something very stupid, but that’s it… 
Can you help me?
So, I went on effect → equalization, and Audacity showed me the graphic wave of my file.
No… It doesn’t do any analysis of the file, it just remembers the last EQ that was done.
If you want to look at the frequency spectrum of the file, go to Analyze → Plot Spectrum. But, that’s not really that helpful for “everyday EQ”. If something is wrong you have to fix it by-ear, or if you like boosted bass, or something like that, you have to do it by-ear too.
NOTE - After making an EQ adjustment the file may go over 0dB and Audacity will change the waveform to red (if you are configured to show clipping) where there is potential clipping (distortion). If that happens, run the Amplify effect or Normalize effect to reduce the level before exporting.
“It doesn’t do any analysis of the file, it just remembers the last EQ that was done”.
Ok, but is there any way to reset the memory, as to say? It is very useful, for me, to start working on the original wave form and not on a flattened one.
Ok, but is there any way to reset the memory, as to say? It is very useful, for me, to start working on the original wave form
If you saved the Audacity Project (AUP file) you can [u]Undo[/u] any effects in “reverse order”.
If you over-wrote the the original file and you didn’t save a project, you’re “on your own” to try and reverse the effect.
… and not on a flattened one.
“Flat” doesn’t flatten… Flat does nothing… It’s the starting-point, similar to bass & treble controls set to the center position where they neither cut or boost the bass or treble.
BTW - Natural real-world sounds don’t have a flat spectrum. The lower frequencies are usually stronger. And, there is no “perfect spectrum”… There are [u]EQ Matching[/u] tools that can analyze two files and equalize the 2nd one so that it’s spectrum matches the 1st (or reference). But, most of the time that would screw-up the 2nd file because they are different music and they should have different spectrums.
EQ is usually used to correct a problem (too much bass or too much treble, etc.). Or, it can be used as an effect/enhancement for people who like to boost the highs & lows, etc.
"If you saved the Audacity Project (AUP file) you can Undo any effects in “reverse order”.
If you over-wrote the the original file and you didn’t save a project, you’re “on your own” to try and reverse the effect. "
I didn’t do any of these actions. I just closed the page, without saving the file as an Audacity Project or overwriting the original source. The problem is that whatever file I open with Audacity (not only THAT one I worked on), if I click on “Equalization” it doesn’t show me the wave form of the file. The effect of the “flat” button has become permanent. How can I reverse this?
The effect of the “flat” button has become permanent. How can I reverse this?
If you apply an EQ curve, Audacity will remember it and you’ll get the same curve next time you open the Equalization effect. You don’t have to save the project or the modified file, but you do have to click to apply the effect. The next time you open Audacity and go to Equalization, you’ll see the same curve.
If you want to apply the same EQ to multiple files you might want to create a custom preset (“Manage Curves”). Then, if you use a different curve or go back to flat, you can always return to your custom setting. Have you read about [u]Equalization in the User Manual[/u]?