In this guide
Add Noise Suppression to the microphone source that is actually being recorded, then compare a short unfiltered and filtered test. RNNoise and Speex have different controls; neither guarantees removal of every sound without changing speech.
To use noise suppression in OBS Studio, add the Noise Suppression filter to the microphone source you are recording. Choose a method available in your installation, record a short test and compare it with the same setup without the filter. Listen to quiet words as well as the background: more suppression is not automatically a better result.
OBS describes its Noise Suppression filter as useful for mild background noise such as a fan, while warning that heavy noise and strong settings can affect the voice. The exact interface and available methods depend on your OBS version, platform and installed components.
1. Record a baseline first
In OBS, check which microphone source moves in the Audio Mixer when you speak. Record a short sample with normal speech, a quiet phrase and a pause while the usual fan or keyboard is audible. Keep the source and distance consistent. Turn off other microphones temporarily if needed to identify the active one, then restore any source you need.
Reduce the problem at capture when practical: move the microphone closer to your voice, point it away from a fan or keyboard, and set input gain while speaking at the loudest expected level. A filter cannot reliably reconstruct speech that was clipped or buried during recording.
2. Add Noise Suppression to the microphone
- Open the source filters. In the OBS Audio Mixer, open the microphone source’s filter controls. The source menu may be reached from its mixer options or context menu, depending on the interface.
- Add Noise Suppression. In the audio filters list, add a Noise Suppression filter. Confirm it belongs to the microphone source rather than a separate game or music source.
- Choose a method. Try RNNoise if it is available, or compare Speex. OBS describes RNNoise as using more CPU and Speex as configurable. The optional NVIDIA method requires its documented SDK; availability depends on the setup.
- Record the same test again. Speak at a comparable distance and level, with the same background sounds. Switch the filter off for another baseline if you changed other settings.
- Listen to the saved recording. Compare the same phrases at similar playback volume. Check consonants, soft words and endings where the noise overlaps speech. Keep a setting only if the voice remains useful.
For Speex, OBS documents a suppression-level control: zero is off and stronger reduction can remove more sound, including parts of the voice. Change it gradually and listen. RNNoise does not use that same Speex slider; do not assume the same controls exist for every method.
Noise suppression vs noise gate
| Filter | What it tries to do | What to check |
|---|---|---|
| Noise Suppression | Reduce some background noise in an audio source. | Whether the voice changes where noise and speech overlap; CPU use can differ by method. |
| Noise Gate | Close or reduce the source when its level falls below thresholds. | Quiet words, breaths and phrase endings can be cut; noise can remain while the gate is open. |
| Gain | Change the level of the source. | It changes wanted speech and captured noise together and does not identify the noise. |
OBS’s noise gate reference describes separate open and close thresholds and timing controls. The microphone noise gate guide covers voice-focused setup and listening checks. If you add a gate, set and test it against your own quiet speech and background rather than copying a universal threshold. Keep the whole filter chain in mind: changing gain or filter order can change what later processors receive.
Troubleshoot common OBS results
| Problem | What to test |
|---|---|
| The background sounds unchanged | Confirm the active microphone, the filter’s enabled state and which recording track you are listening to. Check that you are not comparing a different source. |
| Words disappear or sound watery | Disable the filter for comparison; try a gentler setting or another available method. Also check gates and expanders for cut-off speech. |
| The microphone sounds doubled | Look for duplicate microphone sources or monitoring paths. The microphone echo guide provides a step-by-step check. |
| An expected method is missing | Check OBS’s documented platform and installation requirements. The NVIDIA option requires the specified Broadcast SDK; do not assume a filter exists on every setup. |
| The stream or computer struggles | Compare methods and overall resource usage during a representative test. A result on one computer does not predict another computer’s performance. |
What about noise already in a recording?
Changing an OBS filter affects the signal routed through that source going forward; it does not automatically rewrite an existing saved file. Open the original recording in an editor and choose a method for the sound. A steady fan may suit a noise profile, while a distinct sound overlapping speech may call for a different test. The cleanup method comparison explains the tradeoffs.
For a saved recording, Saturalabs’ voice isolator can test a described spoken voice in a supported MP3, WAV, MP4 or MOV up to 50 MiB. Review Isolated sound against the original: noise can remain and wanted words can change. AI WAV downloads require an account and sufficient credits. This separate service does not install an OBS filter or process a live microphone.
Common questions
Is RNNoise always better than Speex?
OBS describes RNNoise as higher quality with greater CPU use and Speex as configurable. The useful choice depends on your computer and recording. Compare the same phrase and listen for artifacts rather than relying only on the method name.
Will OBS noise suppression remove keyboard clicks?
It may reduce some captured sounds, but clicks that overlap speech can remain or be confused with wanted transients. Improve microphone placement and listen to the actual result; the keyboard-noise guide covers live and recorded workflows.
Can a noise gate remove noise under my voice?
A gate acts on level; when it is open, background sound mixed with the voice can remain. It may also close on quiet words. Test thresholds and timing on a complete phrase.
Does the filter clean an old recording automatically?
No. A saved file needs its own editing or processing workflow. Keep the original and compare the same passage after any cleanup.