What Does the OBS Noise Suppression Filter Do?

The noise suppression filter in OBS Studio is an audio processing tool designed to eliminate unwanted background noise from your microphone signal, ensuring clear and professional audio for your streams or recordings. This article explains how this filter works, the differences between its two processing methods (Speex and RNNoise), and how to quickly set it up to improve your audio quality.

How the Noise Suppression Filter Works

When you broadcast or record, your microphone often picks up ambient sounds alongside your voice. The noise suppression filter analyzes your audio input in real-time and actively removes consistent, non-vocal background noises. It is highly effective at eliminating sounds such as:

• Computer fan whirring and system hums
• Air conditioning units and space heaters
• Distant traffic or wind
• Consistent electrical static and hiss

By filtering out these distractions, the tool ensures that your audience only hears your voice, making your content sound significantly more professional without the need for expensive acoustic room treatment.

Speex vs. RNNoise: The Two Suppression Methods

OBS Studio offers two distinct methods for suppressing noise, allowing you to choose the one that best fits your computer’s hardware capabilities:

1. RNNoise (High Quality, More CPU)

RNNoise is an AI-powered noise suppression method that uses a neural network to identify and isolate human speech from background noise. * Pros: Highly effective, requires no manual configuration, and adapts dynamically to changing background noises. * Cons: Consumes more CPU resources than Speex.

2. Speex (Low CPU Usage, Lower Quality)

Speex is a traditional, algorithm-based noise suppression method. It requires you to manually set a suppression level (measured in decibels) to control how aggressively it cuts out background noise. * Pros: Extremely lightweight on system resources, making it ideal for older or budget computers. * Cons: Can cause your voice to sound metallic or distorted if the suppression level is set too high.

How to Add Noise Suppression in OBS Studio

Adding the noise suppression filter to your microphone takes only a few steps:

1. Open OBS Studio and locate the Audio Mixer dock.
2. Click the three dots (or gear icon) next to your microphone source (usually labeled “Mic/Aux”) and select Filters.
3. Click the + (plus) icon in the bottom-left corner of the Filters window.
4. Select Noise Suppression from the list, name the filter, and click OK.
5. Choose your preferred method (RNNoise or Speex) from the dropdown menu. If you select Speex, adjust the slider until the background noise disappears when you are not speaking.