[Tedd Terry]

Hi Andreas,

I work in iZotope’s QA department. Your distortion problem coincided nicely with some RX testing I was working on. I think I found a way to reduce the level of distortion in that file.

Step 1: Rotate the phase. Open Channel Operations, select the Phase Rotation tab, check ‘Vari phase rotation’ (the lazy way, you can probably find good settings by hand if that doesn’t work for you). This should change the waveform from being asymmetrical (mostly positive) to symmetrical. This will help our Declipper.

Step 2: Declip! This sounded like soft overmodulation of a mic pre, and you can see how some of the waveform peaks are squared off in the distorting parts. I set Declipper to Medium, Clipping Threshold to -11.6, and Makeup Gain to 0.0 (if that’s too hot for the entire interview, you may want to leave it at -6 (default) and adjust the gain later).

Here are my results:

https://www.mediafire.com/?y8bz2unyzq7neai

Not perfect, and maybe some artifacts from the waveform reconstruction declipper performs around 12.4 seconds where the distortion was very heavy, but certainly an improvement.

I hope that helps!