Stereo Tool

There's just not much to go on... It could very well be that what you hear is not so much that a single frequency goes up and down (which could happen to a sine wave and usually isn't very noticeable), but that the relative volume of the different components varies.

Until yesterday I thought that it only happens with asymmetrical sounds, but I found one piece in this U2 track where there's not really asymmetry, but I do see the level go up and down very rapidly in the waveform (as if 2 very-nearby tones were intermodulating). After clipping it sounds bad. It might still be somewhat similar to the asymmetrical and symmetrical with big spikes cases, because half of the time there's almost no audio and the waveform is near-0.

Agreed

I found something that seems to take care of the worst parts (the words 'I'm' and 'Reach'), but it doesn't do much with the rest. Let me know what you think. This is Unveil again, with Smooth Slopes enabled.

EDIT: Better files (old vs. new vs. diff)

OLD: http://www11.zippyshare.com/v/97451916/file.html
NEW: http://www11.zippyshare.com/v/24229597/file.html
DIFF: http://www11.zippyshare.com/v/84993969/file.html

Interesting... When I highpass-filter the both examples with a very steep filter around 200 Hz, NEW sounds way better to me - but if I listen to it without the filter, OLD wins, because to me, it has little more bass and that seems to kind of mask the IMDs a little bit for my perception...

In those phrases you mentioned indeed I do hear a bit of the difference and new wins there. What is better in the new one is that this other distortion (not vibrating) is less audible.

Yup. So there are actually 2 issues here... Anyway, I've noticed now that if I reduce the mids but NOT the bass the effect is nearly the same (of course it's less good but the difference is small). Which is good news: The drop in bass can be skipped.

Because Sloppy was causing annoying artifacts in this situation, I've now also changed the code to turn Sloppy off in this situation (and detection for that is more sensitive than the detection when the mids clipping level must be reduced). By the way, Sloppy at value 141% has 3/4th of the effect of 200%, but with far less effects on the audio.

Ok, I think I've found a sort of 'intermediate' solution: I don't lower the bass anymore but only the mids. This means that distortion isn't fixed completely, but it's still reduced and the 'cold' bass-less sound from the samples I posted earlier is avoided. On top of that, if Sloppy is used I turn it off for the mids when it detects sounds like this. (And also for the highs if there aren't much highs since it turned out that it was causing some crackling sound).

I found something that doesn't really make sense to me: In Composite Clipper mode the real vibrations (not the "I'm" and "reach" in the U2 track) seem to be considerably less noticeable than in non-composite mode. I have no idea why...

New build should be available tonight. It has a new checkbox under Advanced Bass Distortion Protection to turn voice vibration protection on and off.

BETA013 is available for testing!

I'm also still curious about what you hear if you compare these 3 versions:

1. BETA010: http://www.stereotool.com/download/ster ... 52-010.exe
2. BETA011: http://www.stereotool.com/download/ster ... 52-011.exe
3. BETA011A: http://www.stereotool.com/download/ster ... 2-011A.exe

For comparison please USE FM MODE WITHOUT COMPOSITE CLIPPER!

These 3 versions use 3 different masks for vibration removal. So I'd like to know which sounds best.

My rating:
11: worst (vibrations are most present)
10: okay (vibrations still there but I think they are better masked by something in the low-end)
11-A: best (sounds most naturally to me)

Oddly different people are saying different things so I'm waiting for some more feedback...