Denoising A File In Audacity

Denoising is the process of removing unwanted background noise from an audio file.  Following the steps below will guide you through this procedure using the audacity sound editor.

NOTE: In order to make this procedure work you will need a file with discernable noise to remove, the file "Bad Guitar.wav" on the tafn website should work well with this exercise.

1.	Open audacity and load the file.
2.	Press the space bar to run the file and you will hear a loud hum before the guitar starts to play.
3.	If you listen to the entire file, (it's very short), you will hear the hum is present throughout the entire file.
4.	Now play the file again, but after about 1 second, press the right bracket key.
5.	The file will continue to play, you can stop it if you want with the space bar.
6.	Now press the space bar to run the file again.
7.	This time it should only play for a second or so before stopping and all you should hear is the hum.
8.	You have instructed the program to focus only on this section.
9.	Now press the keystroke "Shift+Home".
10.	You have now selected this piece of audio which you will now work on.
11.	You may hear the word "Select", but you may not, this seems to depend on different screen readers and their configuration.
12.	Now press the keystroke "Alt+C" to open the "Effects" menu.
13.	Now press a "U" to go to the "Utility" sub-menu.
14.	Open this sub-menu with a press of the right arrow key.
15.	Arrow down until you hear "Noise removal Sub-Menu".
16.	Open this sub-menu with a press of the right arrow key.
17.	Now arrow down until you hear "Noise Removal…" and press the "Enter" key.
18.	You will now be presented with a dialogue which is asking you to confirm the noise you wish to select.
19.	Press the "Enter" key once and you will be returned to the file.
20.	Now, do the keystroke "Ctrl+A" to select the entire file.
21.	This is necessary to tell the program that the selected noise is to be removed from wherever it occurs in the file.
22.	Ok, some repetition now.
23.	Press the keystroke "Alt+C" to open the "Effects" Menu.
24.	As previously, press the "U" key to open the "Utility sub-Menu".
25.	Arrow down to "Noise Removal Sub-Menu".
26.	Open this sub-menu with a press of the right arrow key.
27.	Now arrow down to "Noise Removal…" and press the "Enter" key.
28.	Now press the "tab" key until you hear "OK".
29.	Press the "Enter" key and the denoising process will begin.
30.	Depending on your machine's speed, you may or may not hear a percentage count up.
31.	Either way, give the program a few seconds to denoise this file.
32.	Remember, this is a very short file, larger files will take longer to process.
33.	Now play the file using the space bar and you should hear nothing for a second or so then a clear guitar sound with no hum.
34.	You have successfully denoised the file.