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# fadeGain(gain:duration:curveType:)

Adjusts the volume of the sounds in a group gradually.

```
func fadeGain(gain: Double, duration: Double, curveType: PHASECurveType)
```

## Parameters

`gain`

The target volume.

`duration`

The total time to complete the volume adjustment. The framework scales this value by [`unitsPerSecond`](/documentation/PHASE/PHASEEngine/unitsPerSecond).

`curveType`

A selection that specifies a mathematical curve that shapes the volume adjustment over time.

---

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