---
title: "fadeRate(rate:duration:curveType:)"
framework: phase
role: symbol
role_heading: Instance Method
path: "phase/phasegroup/faderate(rate:duration:curvetype:)"
---

# fadeRate(rate:duration:curveType:)

Adjusts the playback speed of the sounds in a group gradually.

## Declaration

```swift
func fadeRate(rate: Double, duration: Double, curveType: PHASECurveType)
```

## Parameters

- `rate`: The target playback speed.
- `duration`: The total time to adjust the playback speed. The framework scales this value by doc://com.apple.phase/documentation/PHASE/PHASEEngine/unitsPerSecond.
- `curveType`: A selection that specifies a mathematical curve that shapes the playback speed adjustment over time.

## See Also

### Adjusting Playback Speed

- [rate](phase/phasegroup/rate.md)