---
title: PHASEMetaParameter
framework: phase
role: symbol
role_heading: Class
path: phase/phasemetaparameter
---

# PHASEMetaParameter

A named parameter with a value that the app can change over time.

## Declaration

```swift
class PHASEMetaParameter
```

## Overview

Overview Instances of this class provide an app with dynamic control of a sound’s properties. A metaparameter takes a single value as input and may operate on one or more audio characteristics. To change the value of a metaparameter at runtime: Assign a string to a textual metaparameter’s value. Adjust the value of a number or mapped metaparameter gradually over a duration by calling fade(value:duration:).

## Topics

### Accessing the Value

- [value](phase/phasemetaparameter/value.md)

### Identifying the Parameter

- [identifier](phase/phasemetaparameter/identifier.md)

## Relationships

### Inherits From

- [NSObject](objectivec/nsobject-swift.class.md)

### Inherited By

- [PHASENumberMetaParameter](phase/phasenumbermetaparameter.md)
- [PHASEStringMetaParameter](phase/phasestringmetaparameter.md)

### Conforms To

- [CVarArg](swift/cvararg.md)
- [CustomDebugStringConvertible](swift/customdebugstringconvertible.md)
- [CustomStringConvertible](swift/customstringconvertible.md)
- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)
- [NSObjectProtocol](objectivec/nsobjectprotocol.md)

## See Also

### Base Metaparameters

- [PHASEMetaParameterDefinition](phase/phasemetaparameterdefinition.md)
- [PHASEGlobalMetaParameterAsset](phase/phaseglobalmetaparameterasset.md)