How do you remove white noise from recordings?

Question

Specifically from recordings that other people made.

Answer 1

If you don't have access to a DAW with noise-reduction plugins there is also standalone software designed specifically for this purpose. Audio Cleaning Lab by Magix is a popular one.

Another option is to use a low-pass filter to roll off the very high frequencies where this noise is usually found. However, it's usually difficult to completely remove the white noise without giving the audio a dull muffled sound.

Answer 2

The bad news is that you can't remove white noise from a recording completely. White noise by definition lives all across the frequency spectrum, and can't be distinguished from signal where they both exist.

The good news is that you don't have to. For the most part your brain can't hear noise when it is masked by a real signal in the same frequency range. So the noise reduction approach has two parts:

• where there is no audio signal ("white space" or silences in the recording) just turn the gain down and you remove noise completely. This is "noise gating" and can be done by common plugins.

• where there is signal, use spectral analysis to find out where in the frequency spectrum your desirable signal is, the use equalization to turn the gain down in parts of spectrum where there is nothing but noise. This is one of the main things "denoising" plugins do.

• if you can identify non-white noise elements (hum, pops/clicks) use surgical dynamics and EQ to remove them.

That's the basic forensic audio workflow. It's a hard problem; good luck!

Answer 3

While removing white noise without tampering with the recording is a difficult task, a gate and tweaking of a compressor gets a descent result. of course the best way to achieve a perfect audio sample would be to record the audio again, but since its not your own recording, the gate, a compressor and an 8 band or higher equaliser help.

Answer 4

Waves plug-in's are the best slution if you use DAW for editing and recording. They have X-Hum, X-Noise, X-Click, X-Crackle, Z-Noise plugin's that can solve your problem. They are very expensive plug-in's by the way.

Answer 5

You might be able to use an MP3 encoder for this. Experiment with encoding to MP3s at lower bit rates than you normally would, and it should remove much of the noise while keeping the signal, in a psychoacoustically good way. It will degrade the quality of the recording, but it might be acceptable in a mix with other things.

Answer 6

Adobe Audition has great noise removal. Unfortunately I don't know the specifics, but basically you select an area in which there is only white noise, it analyzes it, and removes that 'type' of sound everywhere else it occurs.

Answer 7

Goldwave is a popular audio editor for Windows that has a noise reduction feature that is quite remarkable.

Answer 8

Audacity has a decent noise removal plugin. It's free!

Answer 9

There are plugins that can do this. As far as I know, the RX Denoiser from iZotope is doing a fabulous job. See http://www.izotope.com/products/audio/rx/