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of what to remove. Then select the '''Effect/Noise Removal...''' option and click on the first button | of what to remove. Then select the '''Effect/Noise Removal...''' option and click on the first button | ||
of the dialog button which it brings up: | of the dialog button which it brings up: | ||
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| + | [[File:noise-removal-1.png|200px]] | ||
== Step 2 - Removal == | == Step 2 - Removal == | ||
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This time you should click on the second button in the dialog. | This time you should click on the second button in the dialog. | ||
The three sliders are worth fiddling with to change how the noise is removed. | The three sliders are worth fiddling with to change how the noise is removed. | ||
| − | I've found they work quite well in the positions shown. | + | I've found they work quite well in the positions shown: |
| + | |||
| + | [[File:noise-removal-2.png|200px]] | ||
== How to improve it further == | == How to improve it further == | ||
Revision as of 07:11, 26 June 2010
You will need an audio editor. This page gives instructions for using audacity's 'noise removal' tool, which does wonders with mucky audio. Remember to keep a copy of the raw, unedited audio just in case.
Contents
[hide]Step 1 - The Sound of Silence
This step 'trains' the computer by explaining what it is that you'd like to eliminate. First, elect a stretch of silence (the longer the better) to the computer can build a profile of what to remove. Then select the Effect/Noise Removal... option and click on the first button of the dialog button which it brings up:
Step 2 - Removal
Once you've done this, that profile lasts as long as the program is running. The final step is to select the region you wish to clean, and choose Effect/Noise Removal... option and click again. This time you should click on the second button in the dialog. The three sliders are worth fiddling with to change how the noise is removed. I've found they work quite well in the positions shown:
How to improve it further
Check that the noise is the same throughout; sometimes the recording may have a different level of background noise. Sometimes, they'll adjust the microphone half way through if they notice the noise, in which case apply the above in two stages.
If the volume level is low, and I've needed to amplify the recording, I've had better results adjusting the volume first and removing the noise second, rather than the other way round.
This is not all you can do with Audacity. There's a bunch more which I haven't got my head round.