best method to use noise reduction

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josephbroadbent
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Joined: Thu Jan 13, 2022 11:21 pm
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best method to use noise reduction

Post by josephbroadbent » Fri Jan 14, 2022 4:23 pm

I use audacity to lay down a backing track and then overdub a saxophone over the backer. I've seen tutorials on using the effects and I see that there are varying ways of applying the noise reduction. One suggests sampling room noise before the recording , another suggests adding the dead space after the recording. Any suggestions on the best way ? Also, if i create a blank recording track then reduce the noise and then enable " repeat noise reduction ", will the repeat effect enable the effect on any additional tracks i record on ? As you can tell i really don't understand what the repeat effect function does. Thanks in advance

kozikowski
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Re: best method to use noise reduction

Post by kozikowski » Fri Jan 14, 2022 5:26 pm

Noise Reduction reduces whatever you put in the profile. So the profile should be as close as possible to the noise in your performance.

You can take the profile from before the performance or after but there are some rules. You, the performer, can't make any noise during those times. So freeze and hold your breath for a second and don't change anything in the room. That's your profile later.

We have you doing that for two seconds in the forum voice test file.

https://www.kozco.com/tech/audacity/Tes ... _Clip.html

Read the blue 'Hold your breath" link.

Noise Reduction will not reduce sounds that aren't noise. Traffic noises, a jet going over, and that TV in the next room aren't noise. They constantly change and it's impossible to get a stable profile. They are now performers in your show.

Koz

kozikowski
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Re: best method to use noise reduction

Post by kozikowski » Fri Jan 14, 2022 5:34 pm

Noise Reduction saves the Last Known Good Profile (last I checked). So technically, you could sample your studio (with you holding your breath and making no noise while you do it) and use that in all your performances, but you can't change anything from that point on. No moving chairs around or opening or closing the drapes or moving the microphone. They all change the noise profile of the room and screw up reduction.

Koz

kozikowski
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Re: best method to use noise reduction

Post by kozikowski » Fri Jan 14, 2022 5:40 pm

Are you beginning to see why it's a terrific idea to work in a quiet studio with a good microphone? You can pile on corrections, tools, and filters, but they all distort the performance a little in addition to doing their job. Then you can pile on more tools to correct the distortions.....etc.

ACX/Audible has a publication submission rejection called "Overprocessing."

Koz

kozikowski
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Re: best method to use noise reduction

Post by kozikowski » Fri Jan 14, 2022 5:42 pm

Missed a step.

https://manual.audacityteam.org/man/noi ... ction.html

And yes, if you noise reduce twice, it will try to reduce twice, but the reduction distortions go up twice, too. Sometimes you can get good reduction by applying gentle reduction twice instead of hard reduction all in one shot.

Koz

josephbroadbent
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Re: best method to use noise reduction

Post by josephbroadbent » Fri Jan 14, 2022 8:25 pm

thank you. Appreciate your help. So if i take a sample and then enable " repeat noise reduction " will that stay in effect until i disable it, even if i record multiple tracks

kozikowski
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Re: best method to use noise reduction

Post by kozikowski » Sat Jan 15, 2022 12:21 am

Where are you getting "Repeat Noise Reduction" from?

Screen Shot 2022-01-14 at 4.11.54 PM.png
Screen Shot 2022-01-14 at 4.11.54 PM.png (81.39 KiB) Viewed 67 times

Are you in Audacity 3.1.3?

Did you get it from here?

https://www.audacityteam.org/

Koz

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