Noise reduction in sections of a track

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kozikowski
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Re: Noise reduction in sections of a track

Post by kozikowski » Sun May 16, 2021 5:34 pm

Which tool do you think has the most effect on voice quality?
Noise Gate doesn't affect voice quality at all. It can affect voice duration.

..esting, One, Two, Three.

or

Testing, One, Two ,Threessss.

TestingsssOnesssTwosssThree.

It's all down to how the gate was designed. Modern Look Ahead Processing goes a long way to preventing evil surprises like cutting off first letters of words.

Another note on that long process. Noise Reduction was used to gently reduce noise between words so when the gate comes along, it doesn't have as much critical work to do and is less likely to damage words and the spaces between them.

Listen critically on headphones to the differences.

Koz

mwhelm
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Re: Noise reduction in sections of a track

Post by mwhelm » Mon May 17, 2021 7:38 pm

All Amplify knows is that somewhere in your hour long presentation, one tiny bit of blue wave was higher than all the others and it latches on that as the reference for the whole show. If that one little wave happened to be noise, then it will push the desired voice into the mud to accommodate that wav. It has no idea what "noise" is.
I discovered this or something similar yesterday before I had a chance to look back at the forum.
I have been experimenting with removing the clicks, coughs, cellphones & other peak noise & that seems to allow the amplify step to work better & the resulting audio is better-sounding.

I've also found that in a lecture type track, if the speaker coughs or a window shutter falls down or chair squeaks, usually the talking stops for an instant. So I can just cut and past quiet moments from nearby over the bad noise & this blip is unnoticeable. And the peak goes away.

Then I realized it's ALWAYS noise in the context I'm working, so I've been experimenting with the Nyquist limiter. This seems to work ok with the whole track - I can suppress peaks without audible damage to the content. (Sometimes the peaks are laughter or people shouting &c & not appropriate to wipe out.) Then I apply normalization (some of the tracks are noticeably off) & this seems to be able to do what amplify goal does; at least the results look and sound the same to me.

At this point I can do an assessment & see if the rest of the toolkit needs to be used. Some are good enough to stop, but most still have hum and some other noise, needing more work.

Thanks for your help!

mwhelm
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Joined: Wed Jun 22, 2016 10:09 pm
Operating System: Windows 7

Re: Noise reduction in sections of a track

Post by mwhelm » Mon May 17, 2021 7:43 pm

Another note on that long process. Noise Reduction was used to gently reduce noise between words so when the gate comes along, it doesn't have as much critical work to do and is less likely to damage words and the spaces between them.
That's good to know. I have been using them in that order anyway because of the organization of the toolkit & the way the menu is sorted, but I have noticed that when I skipped NR it seemed like beginning of some talking was clipped a bit.

Noise gate also seems to suppress bells - some of these tracks have bells, & it must clip the beginning so all you then hear is the ring or reverberation, not the strike.

kozikowski
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Re: Noise reduction in sections of a track

Post by kozikowski » Tue May 18, 2021 9:26 am

Noise gate also seems to suppress bells
Hum Remover might do that. Bells are relatively pure tones and if one of them happens to be a multiple, harmonic, or overtone of the power sound, Hum Remover will try to remove them.

Alternately, if the bell sounds are relatively quiet (background church sounds) they may just fall out of the gate acceptance range. Try juggling the Gate Threshold (dB) setting. You may find that the bells demand one setting and the rest of the show another setting.

I don't think you mentioned this before, but auto noise suppression and echo cancellation looks for sounds like bells. Both of those sometimes built-in services hate music.

Koz

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