I have downloaded an audio book that a friend wants me to help with. It has a constant buzzing sound in the background. Can I remove it - separate it from the voice audio and if so how do I do it? Thanks
You probably can’t remove it completely without causing other noticeable damage to the recording, but you can probably improve it. See here: http://wiki.audacityteam.org/index.php?title=Noise_Removal
For Linux users there is a free program called “Gnome Wave Cleaner” which can do a similar thing, but much better than Audacity.
If it is mains hum try this dehummer plug-in … https://forum.audacityteam.org/t/multiple-notches-with-nyquist-prompt/7583/8
A before-after example is attached, guitar afflicted by Yankee 60Hz mains hum, (the dehummer plugin will remove European 50Hz too)
Guitar_, original-dehummed-dehissed (mp3 in zip).zip (279 KB)
Noise removal is much more graceful and effective in Audacity 1.3 than 1.2.
Hope it is a constant sound. If it’s not, the noise removal software will fail.