godot/doc/classes/AudioEffect.xml

<?xml version="1.0" encoding="UTF-8" ?>
<class name="AudioEffect" inherits="Resource" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../class.xsd">
	<brief_description>
		Base class for audio effect resources.
	</brief_description>
	<description>
		The base [Resource] for every audio effect. In the editor, an audio effect can be added to the current bus layout through the Audio panel. At run-time, it is also possible to manipulate audio effects through [method AudioServer.add_bus_effect], [method AudioServer.remove_bus_effect], and [method AudioServer.get_bus_effect].
		When applied on a bus, an audio effect creates a corresponding [AudioEffectInstance]. The instance is directly responsible for manipulating the sound, based on the original audio effect's properties.
	</description>
	<tutorials>
		<link title="Audio buses">$DOCS_URL/tutorials/audio/audio_buses.html</link>
		<link title="Audio Microphone Record Demo">https://godotengine.org/asset-library/asset/2760</link>
	</tutorials>
	<methods>
		<method name="_instantiate" qualifiers="virtual">
			<return type="AudioEffectInstance" />
			<description>
				Override this method to customize the [AudioEffectInstance] created when this effect is applied on a bus in the editor's Audio panel, or through [method AudioServer.add_bus_effect].
				[codeblock]
				extends AudioEffect

				@export var strength = 4.0

				func _instantiate():
				    var effect = CustomAudioEffectInstance.new()
				    effect.base = self

				    return effect
				[/codeblock]
				[b]Note:[/b] It is recommended to keep a reference to the original [AudioEffect] in the new instance. Depending on the implementation this allows the effect instance to listen for changes at run-time and be modified accordingly.
			</description>
		</method>
	</methods>
</class>