---
title: rolloffFactor
framework: avfaudio
role: symbol
role_heading: Instance Property
path: avfaudio/avaudioenvironmentdistanceattenuationparameters/rollofffactor
---

# rolloffFactor

A factor that determines the attenuation curve.

## Declaration

```swift
var rolloffFactor: Float { get set }
```

## Discussion

Discussion A higher value results in a steeper attenuation curve. The default value is 1.0, and the value must be greater than 0.0. This property is relevant for AVAudioEnvironmentDistanceAttenuationModel.exponential, AVAudioEnvironmentDistanceAttenuationModel.inverse, and AVAudioEnvironmentDistanceAttenuationModel.linear.

## See Also

### Getting and Setting the Attenuation Values

- [maximumDistance](avfaudio/avaudioenvironmentdistanceattenuationparameters/maximumdistance.md)
- [referenceDistance](avfaudio/avaudioenvironmentdistanceattenuationparameters/referencedistance.md)