How To OBS Streaming

How to Understand the Audio Mixer in OBS

Audio is King. There is nothing more important than to make sure your audio is balanced and consistent in order to create the best content for your viewers. So, consider this article the fundamentals of understanding the Audio Mixer in OBS. We’ll be going over the UI and control, and how to read a mixer to balance your audio.

User Interface

The User Interface of the Audio Mixer consists of five components.

  • Volume Meter
  • Fader Slider
  • Volume Level
  • Mute Button
  • Options Button

When it comes to adjusting the User Interface for any audio source, your main goal is to have your audio sources be consistent that you rarely have to adjust any settings in the UI. The only way to make sure that your audio sources are consistent is to be able to read the Volume Meter to detect any inconsistencies with your audio.

Parts of the Volume Meter

Reading the volume meter is overall straightforward, but if there is one thing you should take away from reading the Volume Meter it should be what each zone on the volume meter represents.

There are three zones to the Volume Meter. The green zone, yellow zone, and red zone. When deciding how loud your audio sources should be for your stream here are some good guidelines. Use these as starting points and then determine if the audio source should be louder or quieter.

  • Green Zone – The majority of your audio should be in the green zone. Alerts, game audio, music, sound effects, and any secondary audio sources should be in the green zone.
  • Yellow zone – Consider the yellow zone as the audio you want your audience to stand out and hear above any other audio sources. The best example is your voice and any guests you have on stream.
  • Red Zone – Any audio that is consistently in the red zone needs to have their audio reduced. When an audio source is too high and fills the entire volume meter (reaching 0dB), the audio will become distorted and will be painful for your audience.

While your goal should be consistent audio, you should be flexible and not stress if audio sources enter the start of another zone. I would also recommend testing each audio source as it is good to balance your audio that you’ll want your audience to hear consistently. If you balance your audio based on the loudest part of a song or sound effect, the rest of the audio will be too quiet for your viewers.


While understanding how loud each audio source should be and what zone they should primarily exist in, to get a more accurate understanding from the volume meter, you’ll want to be able to read the indicators. There are four indicators that exist in the Volume Meter. Note that this is based on the volume meter is in horizontal mode.

  • Left Dot – This is the Input Level, the indicator of the volume meter’s status from the audio being output. The left dot will change color based on the green, yellow, and red zones.
  • Main Line – This is the Peak Programme Meter; this is the indicator that you’re used to looking at when it comes to determining if your audio is too quiet or too loud. The moment sound stops being outputted, the Peak Programme Meter will slowly go down (known as the decay rate) until new sounds are detected.
  • Black Dot – This is the Vu-Meter, located on the Peak Programme Meter, this indicator shows the intensity of the audio. Best thought as the part of the volume meter showing the average level of how loud your audio is.
  • Right Dot – This is the Peak, this indicator is also located on the Peak Programme Meter, this indicator displays the loudest the meter has been in 20 seconds. This can help you to see if any of your audio sources are clipping.

You’ll want to rely on the Peak Programme Meter to determine if your audio sources are too high or too low. But each indicator can be used to help you fine tune your audio.


Each source that is capable of outputting audio will be displayed in the Audio Mixer. Each audio source in the Audio Mixer will display the audio based on the number of channels the audio source can output. In OBS, there are three types of channels that can be displayed in the Audio Mixer.

  • Mono – This means there is only one audio channel, viewers will hear this equally in both left and right channels. A good example of an audio source that will only have one audio channel is a microphone.
  • Stereo – Audio is divided between the left and right allowing more nuance based on the direction of the sound. In the Audio Mixer, the left channel is on top while the right channel is on the bottom. A good example of a stereo audio source is your headphones.
  • Surround Sound – Rarely used in conventional streaming setups, surround sound channels consist of three or more channels creating an immersive experience. To enable this option, you must go into the settings and access the Audio tab. If not enabled, OBS will mix down surround sound sources to stereo.

In the rare occasion that you see a stereo audio source only outputting to one channel. It is most likely that it’s a mono source. You can fix this by clicking the gear in the Audio Mixer and select Advanced Audio Properties. From there, you can convert any audio source to output to Mono by clicking the checkbox for that audio source.

Fader Slider, Volume Level & Mute Button

The Fader Slider is how you can control the volume level of audio sources affecting how loud or quiet each audio source is for your viewers. The Volume Level displays how much the audio has been changed by the Fader Slider measured by decibels (dB). Finally, the mute button will mute the audio source preventing your viewers from hearing that audio source.

By moving the Fader Slider to the left, this will cause that audio source’s volume to decrease, and the Volume Level will change based on how many decibels that audio source has been changed by. If you’re finding that an audio source’s volume is too high on the mixer but fine for you, this is when you’ll want to use the Fader Slider. It’s important to understand that what you hear is at a decent volume level could be too loud for your viewers. So, take the time to adjust the audio levels for any videos, games or even your microphone before you start streaming.

If there is an audio source that needs to be muted, each audio source has a mute button that is shaped like a speaker. This is great to use when dealing with audio sources that spike or any other reason that requires you to quickly cut an audio source.

Options Button

The final button in the Audio Mixer is the Options button which is shown as a gear for each audio source. Clicking the gear by the Audio source will cause a pop-up menu to appear giving a list of options to control that audio source. Below is the list and a quick description of each option.

  • Lock Volume – Locks the Fader Slider preventing the audio sources volume to be increased or decreased in the Audio Mixer.
  • Unhide All – Any audio sources hidden will be made visible.
  • Hide – Hides the audio source selected from being seen in the Audio Mixer.
  • Rename – Enables you to rename the audio source in the Audio Mixer.
  • Copy Filters – Copies any filters that exists in the audio source.
  • Paste Filters – Applies copied filters to be applied to another audio source.
  • Vertical Layout – Changes the appearance of the Audio Mixer UI by turning the volume meters from horizontal to vertical.
  • Filters – Opens the filters pop-up window allowing you to add or remove any audio filters to that audio source.
  • Properties – Opens the properties pop-up window for that audio/video source.
  • Advanced Audio Properties – Opens the Advanced Audio Properties pop-up window allowing in depth control of all audio sources.

There are a lot of options that allow you to re-organize your audio sources and directly affect each audio source. I’d recommend using these options where you can only see the audio sources that are being used for each specific scene. As you add more capture cards and other audio devices to your production, you’ll quickly find that having every audio source visible in the audio mixer to be difficult to know which audio source needs to be adjusted. By using these options, you’ll have an easier time reading the Audio Mixer and be able to adjust each audio source as needed.

While the Audio Mixer doesn’t take up much space in OBS, being able to read each audio source and adjust the volume meter is critical for having a successful stream. Once you have learned to read the Audio Mixer in OBS, you’ll find that reading Audio Mixers in other applications and mixers to be easy. You’ll know when an audio source is peaking, how to reduce the volume to an acceptable level, and spot any issues allowing you to troubleshoot.

There is a lot more when it comes to adjusting audio sources such as adding filters but knowing how to understand the Audio Mixer is a great first step to becoming a better content creator.