---
title: AVAudioMixing
framework: avfaudio
role: symbol
role_heading: Protocol
path: avfaudio/avaudiomixing
---

# AVAudioMixing

A collection of properties that are applicable to the input bus of a mixer node.

## Declaration

```swift
protocol AVAudioMixing : AVAudio3DMixing, AVAudioStereoMixing
```

## Overview

Overview Nodes that conform to the AVAudioMixing protocol can talk to a mixer node downstream. This is specific to the classes AVAudioMixerNode and AVAudioEnvironmentNode. Effect nodes can’t talk to their downstream mixer. When connecting a source node, the properties that this protocol defines apply to the respective input bus of the mixer. You can change the state of properties before connecting a source node to the mixer. The system caches your changes and applies them upon connection. It caches the properties again after disconnection. Source nodes maintain mixing settings when switching between different mixers. For example, an AVAudioPlayerNode, in a gaming scenario, can set up 3D mixing settings and then move from one environment to another. important: Several classes adopt the AVAudioMixing protocol. The protocol itself conforms to AVAudio3DMixing and AVAudioStereoMixing. Classes that conform to AVAudioMixing also conform to those protocols.

## Topics

### Defining Mixing Properties

- [AVAudioStereoMixing](avfaudio/avaudiostereomixing.md)
- [AVAudio3DMixing](avfaudio/avaudio3dmixing.md)

### Getting and Setting the Destination

- [AVAudioMixingDestination](avfaudio/avaudiomixingdestination.md)
- [destination(forMixer:bus:)](avfaudio/avaudiomixing/destination(formixer:bus:).md)

### Getting and Setting the Bus Volume

- [volume](avfaudio/avaudiomixing/volume.md)

## Relationships

### Inherits From

- [AVAudio3DMixing](avfaudio/avaudio3dmixing.md)
- [AVAudioStereoMixing](avfaudio/avaudiostereomixing.md)
- [NSObjectProtocol](objectivec/nsobjectprotocol.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)

### Conforming Types

- [AVAudioEnvironmentNode](avfaudio/avaudioenvironmentnode.md)
- [AVAudioInputNode](avfaudio/avaudioinputnode.md)
- [AVAudioMixerNode](avfaudio/avaudiomixernode.md)
- [AVAudioMixingDestination](avfaudio/avaudiomixingdestination.md)
- [AVAudioPlayerNode](avfaudio/avaudioplayernode.md)
- [AVAudioSourceNode](avfaudio/avaudiosourcenode.md)
- [AVAudioUnitGenerator](avfaudio/avaudiounitgenerator.md)
- [AVAudioUnitMIDIInstrument](avfaudio/avaudiounitmidiinstrument.md)
- [AVAudioUnitSampler](avfaudio/avaudiounitsampler.md)

## See Also

### Mixing

- [AVAudioMixerNode](avfaudio/avaudiomixernode.md)