Hunting Washington Forum

Other Hunting => Coyote, Small Game, Varmints => Topic started by: billythekidrock on November 17, 2010, 01:33:30 PM

Title: Audacity Hiss Removal
Post by: billythekidrock on November 17, 2010, 01:33:30 PM: Just got a question on noise removal so I thought I would write up how I do it. This will not work in every situation but it is a fast effective solution for what I need.

Down and dirty hiss removal.

Here is what I do.
After opening or recording a sound file you may notice small sound waves or hear an audible hiss.

(https://hunting-washington.com/smf/proxy.php?request=http%3A%2F%2Fwww.hunt101.com%2Fdata%2F500%2Fmedium%2FAudacityHiss1.jpg&hash=be761a1378b7cdd25433bddf69818a1aee03e975)

I select a small portion of "noise" but nothing that I want to keep.

(https://hunting-washington.com/smf/proxy.php?request=http%3A%2F%2Fwww.hunt101.com%2Fdata%2F500%2Fmedium%2FAudacityHiss2.jpg&hash=83a37355356ec4ac812a774cbe3498ae4eaf6caf)

Then on the menu bar click Effect and then Noise Removal.
In the popup click "Get Noise Profile".
Then click Edit and Select All.
Click Effect and Noise Removal again. This time click Preview or Remove Noise.

(https://hunting-washington.com/smf/proxy.php?request=http%3A%2F%2Fwww.hunt101.com%2Fdata%2F500%2Fmedium%2FAudacityHiss3.jpg&hash=d27590b07295fb095259fa2bc66af71482962ae9)

If needed you can adjust the slider level to remove more or less noise.
Title: Re: Audacity Hiss Removal
Post by: birdshooter1189 on May 07, 2020, 10:04:43 PM: I'm processing some audio right now using your tutorial. I found another way to remove the hiss/background noise that works better for me.

On the main audacity screen, in the assortment of buttons along the top, just to the right of the cut/copy/paste buttons are two buttons that look like waveforms. The button on the right is "silence audio selection".

You highlight a segment of audio file that you want silenced, then click that button and it silences it.
Title: Re: Audacity Hiss Removal
Post by: Fl0und3rz on May 07, 2020, 10:25:01 PM: BTKR method is the way I do it. Trick is finding the sweet spot. Too much noise removal and you introduce non-natural sounding artifacts.
Title: Re: Audacity Hiss Removal
Post by: birdshooter1189 on May 07, 2020, 10:40:38 PM: I see, i misunderstood what he was explaining. His method works great.

I was initially looking for a way to remove the static noises in-between a chicken chick sqwacking in distress. If i selected and hit delete it shortened the clip. I wanted the blank space there, i just wanted to mute everything in-between.

I'm now working on a separate clip where i was transporting 2 cats in my diesel truck and they were meowing profusely. Using the method above was able to remove the sound of the diesel engine (which carried through the cat's meowing) and it got rid of the engine noise both between meows and through the meows.
Title: Re: Audacity Hiss Removal
Post by: Fl0und3rz on May 07, 2020, 11:18:51 PM: You could delete the noise between the sounds of interest and add back silence, I believe, using the same menu path, "generate silence."

BTKR method take a noise profile and subtracts it across the sound of interest. Works well for regular noise such as fan hum. I haven't found a good method for irregular or cyclic noise such as a diesel rumble.