This is a guide on how to install the CoreAudio encoder for audio, which does not come with OBS on Windows by default. This encoder provides much higher audio quality at all bitrates, and is a one time process. Lets begin!

Windows

If you already have iTunes downloaded from the official website (not Microsoft Store), you already have the CoreAudio encoder installed. Skip to setup to use it.

With iTunes (simple)

1. Download the iTunes installer at this link: download
2. Run the installer as normal.
3. Done :)

Standalone install (little more complicated)

If you do not want to use iTunes or want to use iTunes from the Microsoft Store, follow these steps. I would like to thank wordlesswind for their contribution to this method, which you can find here.

1. Download the iTunes installer at this link: download
2. Download this cmd script here: download. This script will extract the CoreAudio dll files from the installer.
3. Place the script file and the iTunes installer file in their own folder.
4. Run the script file (administrator privileges are not required). Wait for the process to complete, which should result in a QTfiles64 folder being generated.
5. Open the QTfiles64 folder and select all the files inside and cut it.
6. Head to the following path in file explorer: C:\Program Files.
7. Create a new folder called iTunes.
8. Open the folder and paste the files into it.
9. Done :)

While the original guide says to install it into the OBS directory, separating external libraries into another folder will make it much easier to see which files belong to OBS and which don't.

Checking if it has installed correctly

1. Open OBS

2. In the menubar, go to Help > Log Files > View Current Log

   

3. Scroll up until you find [CoreAudio encoder]: Adding CoreAudio AAC encoder, if it says that it means you have installed it correctly.

   

Using CoreAudio

If you are using Simple mode, ensure you have selected AAC (default) as your audio encoder. It should prioritise CoreAudio over the internal encoder.

In advanced, you will need to select CoreAudio AAC specifically in the dropdown menu under both Streaming and Recording tabs inside encoder settings. Apart from that, you are all set to go. I would recommend setting an audio bitrate of at least 192kbps, which you can find in the Audio tab.

macOS

Done! You have successfully installed CoreAudio onto your system. Okay in all seriousness you don't have to do anything since macOS already bundles it, and OBS will utilise it.