Desktop Audio vs Mic Aux in OBS Studio
In OBS Studio, managing your sound sources is crucial for producing a professional stream or recording. This article explains the fundamental differences between Desktop Audio and Mic/Aux audio, how they function within the software, and how to properly configure both to ensure your audience hears a balanced mix of system sounds and your voice.
What is Desktop Audio?
Desktop Audio refers to the sounds generated internally by your computer’s operating system and applications. It captures the audio output that you hear through your headphones or speakers.
Common examples of Desktop Audio include: * In-game sound effects and music. * Background music from applications like Spotify or YouTube. * Voice chat from communication apps like Discord or Zoom. * System notifications and browser alerts.
In OBS Studio, Desktop Audio is an output capture. It monitors the designated playback device of your computer and broadcasts whatever sound is sent to that device.
What is Mic/Aux Audio?
Mic/Aux (Microphone/Auxiliary) Audio refers to external sound sources capturing physical audio from your environment.
Common examples of Mic/Aux Audio include: * USB microphones (e.g., Blue Yeti, Shure MV7). * XLR microphones connected via an audio interface. * Headset microphones. * External instruments or mixers plugged into your computer’s line-in port.
In OBS Studio, Mic/Aux is an input capture. It takes sound waves from the physical world, converts them into digital signals, and brings them into your stream.
Key Differences Between Desktop Audio and Mic/Aux
| Feature | Desktop Audio | Mic/Aux Audio |
|---|---|---|
| Source Type | Internal (System Output) | External (Physical Input) |
| Primary Purpose | Capturing game sound, music, and voice chat. | Capturing your voice or live instruments. |
| Direction of Signal | Outgoing from the computer to your ears. | Incoming from the room to the computer. |
| Default Muting | Usually kept unmuted unless copyright music is playing. | Frequently muted/unmuted (push-to-talk) to hide background noise. |
Why Keeping Them Separate Matters
OBS Studio displays these two sources as separate tracks in the Audio Mixer. Keeping them distinct is essential for several reasons:
- Volume Balancing: Game audio is often much louder than a microphone. Having separate sliders allows you to lower the Desktop Audio so your voice (Mic/Aux) remains clear and audible.
- Multi-Track Recording: If you record your videos, OBS allows you to export Desktop Audio and Mic/Aux on separate audio tracks. This is invaluable during video editing, as you can adjust or mute game sounds without affecting your commentary.
- Filters and Processing: You apply different filters to different sources. Your Mic/Aux will benefit from filters like Noise Suppression, Noise Gate, and Compressor to clean up background noise. Applying these to Desktop Audio would ruin the sound quality of your games or music.
How to Configure Both in OBS Studio
To set up or change these devices:
- Open OBS Studio and click on Settings (bottom right).
- Select the Audio tab from the left menu.
- Under Global Audio Devices:
- Set Desktop Audio to “Default” or select your primary listening device (e.g., your headphones).
- Set Mic/Auxiliary Audio to your specific microphone.
- Click Apply and OK.
Both sources will now appear in your Audio Mixer on the main screen, ready for individual volume adjustment.