The words “neural network” can sound like a mystery, but the idea behind neural noise reduction is simple to explain. The tool has learned what speech tends to look like, and what noise tends to look like, from many examples. It then applies that learning to your recording.
Learning from examples
During training, the network is shown many pairs of clean speech and speech mixed with noise. It learns to predict the clean speech from the noisy version. Over many examples, it builds up a sense of which sounds are voice and which are background.
Applying it to your recording
When you use the tool, it looks at short slices of your audio and estimates how much of each slice is speech. It then reduces the parts it judges to be noise. Because it works on patterns, it can handle many kinds of everyday noise, such as fans, traffic and room hum.
Why it is not perfect
The network makes estimates, and every estimate can be wrong. It can remove part of the voice, leave a little noise, or treat a sound that is part of the performance as background. This is why the setting matters, and why listening is essential.
What it does well
- Steady background noise on clear speech.
- Everyday rooms, with fans, hum and traffic.
- Quick cleanup of many similar files.
What it does less well
It struggles with distant voices, clipped audio and several people talking at once, as covered in the limits post. A good recording is still the best input.
Limits
Explaining the method does not tell you how a particular product performs. Test any tool on your own recordings, and judge the result by ear, on the devices your listeners use.
Try it free: Noise-Free Voice Recorder
Record voice-overs with live noise removal, or clean an existing file. Runs in your browser, nothing is uploaded.
Frequently asked questions
Does the network understand the words?
No. It estimates speech and noise from patterns in the sound.
Is neural noise reduction the same as a filter?
Different. A filter removes fixed frequencies, while a network adapts to the sound it hears.
Why does it sometimes sound watery?
The estimate removed some of the voice along with the noise. Use a lighter setting.
Do I need to understand the maths to use it?
No. Listening to the result and comparing with the original is enough to judge it.
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