Have I been removing clipping wrong?

I have some old master recordings I was thinking of editing again from scratch for better sound. They were very clipped but I used an old youtube tutorial found here: https://www.youtube.com/watch?v=KM5shJycg9k&t=1s to clean them up. Essentially what was done was deamplify 6db, copy and paste a second copy of the tracks, EQ one to have no bass under 80Hz, and the other track that’s just the bass, silencing the rest, then lower gain on the bass, export, amplify. I was left with not the greatest EQ setting, and for best results I know you should try to EQ as few times as possible, but it also created white noise. Now I know there is a clipfix plugin, would it fix the issue better? It seems to give me better looking waveforms that don’t look shaved, but there is still a tad of distortion that can be heard. Is the old method in this guy’s video actually, good, are are there some redundancies. The audio sent through his method actually doesn’t sound too bad, but the waveforms aren’t pretty. Also it is possible that newer versions of clipfix are better now, and I should upgrade audacity. I know steve and others have been doing this for years, so just curious what the veterans think. The audio is heavily clipped at times, and I know that a perfect result isn’t possible, but the best result is desired

Good luck. Clip Fix works hard to approximate the original signal in one clip event in the middle of a clean presentation. It “guesses” at what the original work might have been had it not been damaged based on the surrounding work. In all cases, it goes for waveform integrity, not pleasant sound.

A while back “Noise Removal” was quietly renamed “Noise Reduction.” Too many people were expecting it to completely remove all noise.

This tool might more properly be named Fix One Clip Point.

Koz

Well yeah, I said I wasn’t expecting perfect results, just the best that I can get, that is why I asked about the method used in the linked video and whether or not that is a better approach, or if I should try something different. I’m not looking for a one click solution, or perfect audio quality. but just want to know the most sensible approach to tackling the situation at all.

Essentially what was done was deamplify 6db, copy and paste a second copy of the tracks

Regular-linear volume adjustments have no effect on sound quality unless you amplify into clipping or if you reduce the volume by an extreme amount. (The quality/resolution of the low-volume file isn’t reduced until you export.) And you won’t actually hear any quality loss from reducing the volume unless you re-amplify it later.

Audacity isn’t checking the wave shape. It’s looking for potential clipping. If you reduce the level you can “hide” the clipping because it won’t “show red” if the peaks are reduced below 0dB. Or you can get a false-positive (showing red) if you do something to temporarily go over 0dB.

EQ might help with the overall sound and it will change the wave shape which can “hide” the clipping visually.

BTW - EQ can often push the peaks over 0dB (especially if you boost the bass). In that case Audacity will “show red”, but the actual audio data isn’t actually clipped (unless it was already clipped) and you are safe as long as you reduce the levels before exporting.

Now I know there is a clipfix plugin, would it fix the issue better? It seems to give me better looking waveforms that don’t look shaved, but there is still a tad of distortion that can be heard.

I got similar results when I tried it once or twice… The waveforms looked better but it still sounded distorted.

It might work best with “clean digital clipping” and I’m sure it works better with slight clipping but I haven’t used it that much.

It can’t work perfectly because with clipping information is permanently lost and it’s impossible to know the original height or shape of the waveform. In general, "You can’t fix distortion". :frowning:

Acon De-Clip works in Audacity on Windows
https://youtu.be/Bf2lgyzv8-8?t=407
IIRC you can try before you buy