How to Use an OBS Noise Gate or Expander
A noise gate or expander reduces microphone sound when it falls below a chosen level. These filters can make room noise less noticeable between sentences, but they do not remove noise while you are speaking.
Use a gate for a more definite cutoff or an expander for gentler reduction. Start with one rather than stacking both without a clear reason.
Add the filter to the right microphone
- 1.Find your microphone in the Audio Mixer.
- 2.Open its menu and select Filters.
- 3.Click + in the audio filters list.
- 4.Select Noise Gate or Expander.
- 5.Confirm the name and record a test after adjusting it.
Listen to your actual microphone first. If it is already distorted or barely captures your voice, correct that before adding filters.
Set a noise gate
The Open Threshold is the level needed to let sound through. The Close Threshold is the level below which the gate closes.
Set the opening level above the room noise but low enough for quiet speech to open it. Keep the closing threshold lower than the opening threshold so the gate is less likely to flutter around one boundary.
The timing controls affect how naturally it operates:
- Attack: how quickly the gate opens.
- Hold: how long it remains open after the level drops.
- Release: how gradually it closes.
A very fast close can cut off the ends of words. Do not assume the supplied defaults fit your microphone, distance, and room.
Set an expander
An expander reduces sound below the Threshold according to its Ratio. A lower ratio applies gentler reduction; a higher ratio moves closer to gate-like behavior.
Begin with the Expander preset and adjust the threshold while listening to both room noise and your quieter voice. Use attack and release to prevent abrupt changes. OBS's RMS detection option averages short-term levels, which can make the response less sensitive to brief peaks.
The expander is commonly placed after compression and before a final limiter. Test the whole filter chain, because one filter can change the level reaching the next.
Check words, breaths, and pauses
Record normal speech, a quiet sentence, and several pauses. Listen for missing syllables, sudden background changes, or a microphone that sounds as though it switches on and off.
If speech is being cut, reduce the threshold or soften the reduction. If background noise remains during speech, a gate cannot solve that part of the problem; improve the room/microphone setup or consider mild noise suppression.