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# PHASEDistanceModelFadeOutParameters

A distance over which the framework fades out sound.

```
class PHASEDistanceModelFadeOutParameters
```

## Overview

For spatial sound output, the framework stops playing a sound when its distance from the listener surpases [`cullDistance`](/documentation/PHASE/PHASEDistanceModelFadeOutParameters/cullDistance). The framework gradually fades out the sound’s volume as the distance between the source and listener approaches [`cullDistance`](/documentation/PHASE/PHASEDistanceModelFadeOutParameters/cullDistance). Likewise, the framework gradually fades in the sound as the distance between the source and listener approaches `0`. A [`PHASEDistanceModelParameters`](/documentation/PHASE/PHASEDistanceModelParameters) object provides an instance of this class to a spatial mixer; for more information, see [`fadeOutParameters`](/documentation/PHASE/PHASEDistanceModelParameters/fadeOutParameters).

### Specifying a Maximum Distance That Sound Reaches

The following code demonstrates a spatial mixer’s additional fade out. By setting `fadeOutLength` to `1.0`, the framework begins to fade out a sound after its distance to the listener surpases `1.0`.

```objc
PHASEDistanceModelFadeOutParameters* fadeOut = 
    [[PHASEDistanceModelFadeOutParameters alloc] 
        initWithMaximumDistance:10.f 
        fadeOutLength:1.f curveType:PHASECurveTypeLinear];
piecewiseModel.fadeOutParameters = fadeOut;
spatialMixer.distanceModelParameters = piecewiseModel;
```

## Topics

### Creating the Distance Model Fade-Out Parameters

[`-  initWithCullDistance:`](/documentation/PHASE/PHASEDistanceModelFadeOutParameters/init(cullDistance:))

Creates a distance beyond which sound sources stop playing.

### Inspecting the Cull Distance

[`cullDistance`](/documentation/PHASE/PHASEDistanceModelFadeOutParameters/cullDistance)

The distance beyond which the framework doesn’t process the sound.

## Relationships

### Conforms To

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

[`Hashable`](/documentation/Swift/Hashable)

[`CVarArg`](/documentation/Swift/CVarArg)

[`Equatable`](/documentation/Swift/Equatable)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

---

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