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# rolloffFactor

A value that fades specific frequencies over a distance.

```
var rolloffFactor: Double { get set }
```

## Discussion

The framework clamps a value to the range `[0.0,` <doc://com.apple.documentation/documentation/Swift/Double/greatestFiniteMagnitude>].

A roll-off effect changes the frequencies of a sound as it dissipates with distance. A value of `0.0` disables the roll-off effect. A value of `0.5` halves the roll-off. The default value is `1.0`, which produces a realistic roll-off effect. A value of `2.0` amplifies the roll-off effect.

---

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