---
title: distanceModelParameters
framework: phase
role: symbol
role_heading: Instance Property
path: phase/phasespatialmixerdefinition/distancemodelparameters
---

# distanceModelParameters

An effect that changes sound as it carries over a distance.

## Declaration

```swift
var distanceModelParameters: PHASEDistanceModelParameters? { get set }
```

## Discussion

Discussion Similar to a Doppler effect, this property changes how an audio source sounds as its distance between the listener increases or decreases in 3D space. The available options are: Programmatically Check Sound Dissipation After setting a value for this property, you can move a looping sound source to tweak the effect to your app’s particular requirements. The following code programmaticaly moves a looping source away from the listener along the z-axis: