How to clean up audio recorded in a car

A vlog from the driver's seat, a voice note on the way to work, an interview in a parked car, kids singing in the back. The car is one of the places we record most, and one of the noisiest. The upside: most car noise is steady, and steady noise is exactly what noise removal handles best.

Why car recordings sound bad

• Engine and road rumble. A low, constant sound that grows with speed and sits right under the voice.
• The fan. Air conditioning and heating add a steady hiss that covers the upper part of speech.
• Wind. An open window or sunroof at speed blows straight into the phone microphone.
• Vibration. A phone in a dashboard mount picks up bumps and rattles through the mount itself.
• The radio. Music under a voice is the hardest thing to remove later.

Before you record: five quick fixes

1. Close the windows and sunroof. This alone removes most wind noise.
2. Turn the fan down or off for the few minutes you are recording.
3. Turn off the radio. A noise remover can take out an engine, but music is much harder to separate from a voice.
4. Bring the microphone closer. Mount the phone near face height rather than low on the dashboard or in a cup holder, or use a wired clip-on microphone.
5. Park if you can. With the engine off, a car is a surprisingly good place to record: the seats and headliner soak up echo.

On iPhone 16 or later, also check that Wind Noise Reduction is on in Settings > Camera > Record Sound. It is on by default and works while you film.

Clean it up with the tools on your iPhone

• Videos from iPhone 16 or later: open the video in Photos, tap Edit, then Audio Mix, and choose Studio. Use the slider to lower the background.
• Voice memos: open the recording in Voice Memos, choose Edit Recording and tap the magic wand to turn on Enhance Recording. It reduces background noise and echo in one tap.

Both are free and fine for light noise. They give you little control, though, and Audio Mix only works on videos recorded with Spatial Audio on a recent iPhone.

Clean it up with Denoise.FX

Denoise.FX removes engine, road and fan noise from both video and audio, on any iPhone with iOS 15 or later. It runs entirely on the device, so it works on the road even without a signal.

1. Import the recording. Tap Photos for a video, Files or Music for audio, or Record to capture something new right in the app.
2. Listen. The app cleans the sound in Optimal mode straight away. Switch between Original and De-noised while it plays to hear the difference.
3. Apply the car settings below in the denoise settings. The app processes the recording again.
4. Save the result to Photos or Files. Your original stays untouched.

A starting recipe for car audio

• Mode: Optimal for city driving. Best quality for highway speeds, an open window or a loud engine; it takes longer and needs iOS 16 or later.
• High pass filter: on, between 80 and 150 Hz. It cuts the engine and road rumble below the voice. Above about 150 Hz the voice starts to sound thinner.
• Strength: full by default. If the voice sounds hollow, lower it a little.
• Volume boost: if the person speaking was far from the phone, for example in the back seat.

What to expect

• Engine, tires and fan: steady noise, removed well.
• Wind from an open window: much better, especially with Best quality. Gusts strong enough to overload the microphone cannot be fully repaired.
• The radio: reduced, but rarely clean. Turn it off next time.
• Short sounds like turn signal clicks or a pothole bump may still be faintly audible.

Questions

Will it remove the passengers' voices?

No. The models are trained to keep speech, so everyone talking stays in the recording. Voices closer to the phone will simply sound clearer than distant ones.

Does it change the video?

Only the sound. Denoise.FX copies the picture as it is, without re-encoding, and saves the result as a new video.

Does it work without an internet connection?

Yes. Everything happens on the iPhone, and nothing is uploaded. The app works in airplane mode.

For other kinds of noise, such as wind outdoors, traffic or a noisy room, see how to remove background noise from a video on iPhone.