How to remove background noise from audio without ruining the voice

Almost every home recording has some noise: the air conditioning, the computer, the fridge, street traffic or the microphone's own hiss. You don't notice it while recording, but on headphones it shows up as a background bed that tires the listener and sounds unprofessional. The good news is that constant noise can be reduced a lot. The bad news is that some noises no tool removes well, and it's worth knowing which before you start.

Which noises can be removed

The reason is simple: noise reduction algorithms learn what the background noise sounds like and subtract it. If the noise is steady, they learn it well. If it's a one-off bang or, worse, another human voice, it gets confused with what you want to keep.

The modes, explained

• Voice: uses RNNoise, a small neural network trained on speech. It separates the voice from what surrounds it and is the best choice for podcasts, interviews, meetings and voice notes.
• Music & general: measures the noise in the quietest passages and subtracts it from the rest. It respects instruments and ambient sounds better.
• Auto: detects whether the recording is mainly speech or music and applies the right treatment. The best starting point if you're unsure.

Step by step

1. Use the best version you have. If there's a WAV and an MP3 of the same recording, upload the WAV: compression blends noise into the voice and makes it harder to separate.
2. Start on Auto at 65%. It's a middle ground that works on most recordings.
3. Turn on extras only if needed. The low-cut filter removes rumble below 80–100 Hz; the hum option removes the 50 Hz of European mains power (60 Hz in the Americas) and its harmonics.
4. Compare on headphones. Switch between original and clean on a passage with speech and on a silence.
5. Adjust and download. In the original format or as WAV, MP3, FLAC or OGG. The clean file is exactly as long as the original.

Mistakes that ruin the voice

• Overdoing the strength. The classic symptom is a metallic, hollow or 'underwater' voice. It's better to leave a little noise than to wreck the voice: lower the strength until that effect disappears.
• Cleaning at the end of the chain. Remove the noise before equalizing, compressing or boosting the volume. Boost the volume first and you boost the noise too.
• Judging only on laptop speakers. Many low noises aren't audible on small speakers. Listen on headphones.
• Expecting miracles. A recording made three metres from the microphone in an echoey room will still sound distant even without noise.

After cleaning

Once the noise is gone, the voice usually benefits from two touches. With the equalizer, a low-cut filter and a small lift between 2 and 5 kHz add presence; if it sounds boxy, a gentle cut between 250 and 400 Hz helps. Then the volume booster in Normalize mode brings it to a comfortable level that's consistent between episodes. We go into more detail in our equalizer guide.

Prevention beats cleanup

• Turn off the air conditioning and fans while you record.
• Record in the room with the most furniture, curtains and rugs: they absorb echo.
• Get close to the microphone. The louder your voice arrives, the less the noise shows.
• Record ten seconds of silence at the start: it helps you check what noise the room has.

FAQ

Can it remove background music from a video?

No: music isn't constant noise. To separate a voice from music, use the Vocal Remover, which extracts the voice as a separate track.

Do I have to redo the settings for every episode?

If you always record in the same place with the same microphone, the settings that worked once usually work for the next ones. Note them down (mode, strength and extras) and do a quick before/after check on each new recording.

Is my recording uploaded to a server?

No. Both RNNoise and spectral reduction run in your browser, and the file never leaves your device.