Removing background noise from recorded meetings - Page 1
Forum section: electronics / beginners

author: watchmaker
author_rank: Unknown
timestamp: April 24, 2025, 11:55:00 am
content: Mary and I have been hosting monthly talks about New Hampshire landscape at the local library. I am using a camcorder with a Rode mic.But I pick a lot of fan noise which destroys the audio.What is a good program for filtering out the background noise (mainly fan; some room acoustics)?THANKS!Dewey

author: Andy Watson
author_rank: Super Contributor
timestamp: April 24, 2025, 01:57:28 pm
content: I have used Audacity to remove noise from recordings. Works best if the noise is stable, consistent, and you have several seconds of "pure" nosie to use as a refrence.

author: themadhippy
author_rank: Super Contributor
timestamp: April 24, 2025, 02:04:11 pm
content: Audacity,its has a noise filter were you give it a sample of the noise you want remove set the reduction level and let it do its thing,it also has a filter thingy that can can be set as a fairly narrow notch filter.

author: jmelson
author_rank: Super Contributor
timestamp: April 24, 2025, 03:48:28 pm
content: It seems like it would be much better to remove the noise BEFORE it gets into the audio stream. Possibly by using a directional mike, or a hand-held mike that is handed to the speaker, or a fixed mike at a lectern. Trying to remove the noise AFTER recording seems difficult, but maybe modern AI can do magic.Jon

author: GLouie
author_rank: Regular Contributor
timestamp: April 24, 2025, 04:00:34 pm
content: Agree with jmelson. The filtering options can be difficult and expensive, although what's available may be fine for you. Best to mike the audio more carefully, which isn't what casual users want to do as it's a lot of work. That's the price for good audio. Is the Rode mic on the camera? One of Rode's solutions is a wireless mic system; put the mic near the talkers and the receiver goes into the camera.One of the most popular audio noise fixers is iZotope RX, but it is expensive ($99USD) to very expensive ($1200) and has a steep learning curve. For free, you may find Audacity filtering acceptable, or at low-cost (basically free for unrestricted trial), Reaper.

author: BeBuLamar
author_rank: Super Contributor
timestamp: April 24, 2025, 04:41:24 pm
content: Quote from: jmelson on April 24, 2025, 03:48:28 pmYes it's much easier and better to remove the noise during the recording like using separate close mike for each person but what's done is done. I don't think the OP has he ability to redo the meetings.

author: David Hess
author_rank: Super Contributor
timestamp: April 24, 2025, 05:15:03 pm
content: Quote from: watchmaker on April 24, 2025, 11:55:00 am20 years ago Soundforge had a function where an FFT was run on an example of the background noise and the results were used to configure a frequency selective noise gate. This works incredibly well for removing background noise.

author: SteveThackery
author_rank: Super Contributor
timestamp: April 24, 2025, 05:30:44 pm
content: Quote from: David Hess on April 24, 2025, 05:15:03 pmAnd every present day audio workstation program offers the same feature. It's pretty effective, but it's not smart: if voices or other wanted sounds intrude into the filtered frequencies, then they will be affected.

author: David Hess
author_rank: Super Contributor
timestamp: April 24, 2025, 05:56:26 pm
content: Quote from: SteveThackery on April 24, 2025, 05:30:44 pmI have not used anything modern, so limited my observation to Soundforge. I assume that it has been a standard feature for decades.When you select the sample of noise for analysis, do not select any part which includes voices.

author: watchmaker
author_rank: Unknown
timestamp: April 24, 2025, 08:46:50 pm
content: Guys, I hate to admit it, but I DO have my issues.I had the damned mic plugged into the headphone jack. OOPS!!I will try Audacity to clean up my screwed up recording. Will do it correctly tonite.