U3D-AudioMixer

AudioMixer is a Unity script written in C# that attempts to implement an audio mixer with channels. In Unity, the most typical way to control audio was though priorities, which could be set in a sound's properties. There was never a built-in system to relay audio to a specific channel.

AudioMixer implements audio channeling via a script with the same name that is attached to a GameObject. Entities in your game that need to play a sound (or music) can call AudioMixer to play a sound in a specified channel of your choice. Notice that this is not a Unity extension and thus does not make audio channels a built-in feature in Unity.

AudioMixer was made for music and 2D sounds in mind. This is not recommended for 3D sounds. 3D sounds require a location, which would be too cumbersome to implement in AudioMixer.

You can read my reason for start this here.

Demo Scene

The demo scene ( AM_TestScene.unity ) features an array of keys on the screen that play sound in multiple channels. By default there are 8 channels and 2 sounds to test per channel for a total of 16 sounds.

You should be able to play audio from multiple channels at the same time. If you play a sound for channel X and then play another sound that is also for channel X, the first invoked sound stops immediatly and the second sound plays at that channel.

Channel 1 plays looping music. The rest are sound effects or jingles.

The demo project requires Unity 4.2 or greater.

The functionality of the keys can be changed by clicking on a key in the scene and adjusting the inspector.

How to Use

Put the AudioMixer.cs script somewhere in your /Assets folder. Then place the prefab AudioMixerObject.prefab into a folder called /Resources. This folder must be somewhere in the /Assets folder, so for example: /Assets/Resources/AudioMixerObject.prefab.

The next step in important if you're placing AudioMixer into a new Unity project. Go to the AudioMixerObject prefab and in the inspector, make sure the AudioMixer script is attatched. It most likely will not be attatched if you took AudioMixer assets into a new project.

Whenever you want to play a sound in code, you can call the AudioMixer like this:

using UnityEngine;
using System.Collections;

public class SoundPlayerScriptExample : Monobehavior
{
    public AudioClip soundEffect;
    public int audioMixerChannel = 1;
    public AudioMixerChannelTypes audioType = AudioMixerChannelTypes.Sound;
    
    void Start()
    {
        AudioMixer.Play(audioMixerChannel, soundEffect, audioType);
    }
}

Notice that this is a static call. An instance of the AudioMixerObject prefab will be created when needed, so you don't have to.

Be default, AudioMixer sets up 8 channels (which are actually AudioSources). If you would like more channels, change the constant NUM_OF_CHANNELS, which can be found right after AudioMixer's class declaration. Notice that changing this constant will NOT adjust anything in the demo scene.

Documentation

For documentation, please refer to the wiki.