I've been in audio restoration for over 13 years and have yet to hear a "perfect" declipper.


That said, the samples did sound great but not perfect. Californication is still un-fixable from a retail CD copy.


I'll dig around some more and let you know.

Hmmm....I'll have to keep this in the toolkit.  iZotope RX has a declipper that has helped me out in a few cases.  Next time I come across something rough I'll have to run a comparison.

I've been using iZotope's declipper for various badly recorded dialogue and it works very well for that. Didn't have the same luck with it when it comes to taming brickwalled masters though.

This is why brickwalled stuff can't really be fixed.


All declippers are made to fix simple "overs" like during a radio broadcast or an interview recording. For these things, declippers are life savers at times. However, throw something complex at them and they all have problems.


As for perfect declipper...it's far from perfect but I can see how people would think it's a miracle worker.


I ran my typical test track through it....Don't Know Why by Norah Jones. Even on simple jazz, the Perfect Declipper was unable to fix the distortion from the few overs that recording has. It performed on par with Izotopes algorithm, if not slightly worse. HOWEVER...it did make the waveform look beautiful.


Running a few other test tracks I use produced about the same results. Perhaps I need to get more finicky with the settings or pick different tracks but from the dozen or so tracks I threw at it, it didn't really perform like I would have liked.


If you're thinking of buying a declipper...Izotope is the one to get...for simple stuff that is. 

♪ you'll~  be~~ on~~ my~~ mind  ♪
The distortion there always ticked me off 

The thing I don't like about RX3 and RX2 and other declippers is that they are controlled by a linear threshold. Using it on a single track is great, but on a whole track the lower volume clipped stuff below the threshold doesn't get fixed (Correct me if I'm wrong)

Thanks for the help LFF 

YUP! I love when they use that track at audiophile conventions. When you don't hear that distortion = system not resolving enough = no purchase or interest from me.    (unless they have my remaster!)


Now as for your other question....now that's where I earn my money! Great question!!!!


Yes, most people feel that running the entire mixed song through any declipper fixes the loudness war problem because the waveform looks better but it will not sound better....just sound different at a lower volume which tricks people into believing it does sound better due to better dynamic range. While there might be more dynamic range due to the reconstructed peaks, the clipped distortion remains and there is no way to fix that properly.


You're completely correct! You need to grab the individual tracks (ie, piano track, vocal track, bass track, etc) and run them individually through a declipper using the linear threshold to get the proper result. Even then, the reconstruction might not be optimal or may not sound good. It ultimately comes down to tracking the individual mics properly during the recording session and pretending there will be NO POST work.


I absolutely hate when someone says "Don't worry...we'll fix it in post!" 

Just tried it today. It didn't really do anything for most of my music but there were a few tracks that were clipped to hell and it definitely made a difference there.