Windows Freeware Guide: ocenaudio (FREE) – Remove Noise from Audio on Windows

The manual of Audacity (FREE) has a title ‘Noise reduction & removal’. But I don’t see the menu that has a word ‘remove’, or ‘removal’ or any word that has the same meaning. The manual I mentioned is here: https://support.audacityteam.org/repairing-audio/noise-reduction-removal

Ocenaudio has it, but before I talk about that feature, let me take some lines talking about ‘Noise Reduction’ because I think I see a connection between ‘Reduction’ and ‘Removal’.

The test steps – ocenaudio 3.14.7

On: Windows 11 Home

Download: https://www.ocenaudio.com/

1. Download a file from a link above and install it.

I dropped a .m4a file into the program’s window.

In the picture above, in the red circle is noise.

Drag to select a part of noise.

Go to menu Effects > Noise Reduction > Noise Reduction…

At tab ‘Noise Profiler’, click ‘Get profile’. I think the app will create a profile of the noise that I selected.

At tab ‘Noise Reductor’ > at ‘Output’, select ‘Reduce noise’.

Then click ‘Apply’. The app will reduce noise in the selected area.

In the picture above is the result of noise reduction.

Noise in area 1 and 2 of the picture above were not selected, so the app did not touch them.

Noise in area 3 and 4 were reduced.

I think noise in area 5 was untouched, it might be because the app thinks this is the audio not noise. In my theory, the app defines noise by size of audio shape. If there are several sizes, shape that has the lowest size but higher than the silent level (flat line) is considers as noise. So the app didn’t consider noise in area 5 as noise because there were other lower shapes.

I use my theory to understand what this app does.

Then I selected every part of track by pressing Ctrl+A. I clicked menu ‘Noise Reduction’ and clicked ‘Apply’ to reduce noise using the same noise profile. The picture below is the result.

Look at the area 1 in the picture above, it turned to flat line that means there is no noise or noise was removed. From this situation I can tell that with the same noise profile and set output to ‘Reduce noise’, if I click ‘Apply’ 2 rounds, noise will be removed.

Area 2, noise is reduced because I click ‘Apply’ one round.

2. I started from the beginning – imported .m4a file to the app. Here are the steps:

Select a part of noise in the track > Get profile > Close a window of ‘Noise Reduction’ > Select every part of track using Ctrl+A > Go to menu ‘Noise Reduction…’ > At tab ‘Noise Reductor’ > at ‘Output’, select ‘Reduce noise’ > Click ‘Apply’.

The picture below is the result.

3. It’s time to remove noise. I repeated what I did in step #2 of this post except for one thing, at tab ‘Noise Reductor’ > at ‘Output’, select ‘Remove noise’.

The picture below is the result.

To remove multiple parts of audio, drag to select part 1 then hold down ‘Ctrl’ key while dragging to select part 2, part 3…

Right click and select ‘Cut’.

If you don’t want to remove audio, you can remove the remaining noise by selecting a noise area > get profile > reduce or remove noise at selected area. This way a duration of file is untouched.

4. Save a noise profile for future use.