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# AVAudioUnitDelay

An object that implements a delay effect.

```
class AVAudioUnitDelay
```

## Overview

A delay unit delays the input signal by the specified time interval and then blends it with the input signal. You can also control the amount of high-frequency roll-off to simulate the effect of a tape delay.

## Topics

### Getting and setting the delay values

[`delayTime`](/documentation/AVFAudio/AVAudioUnitDelay/delayTime)

The time for the input signal to reach the output.

[`feedback`](/documentation/AVFAudio/AVAudioUnitDelay/feedback)

The amount of the output signal that feeds back into the delay line.

[`lowPassCutoff`](/documentation/AVFAudio/AVAudioUnitDelay/lowPassCutoff)

The cutoff frequency above which high frequency content rolls off, in hertz.

[`wetDryMix`](/documentation/AVFAudio/AVAudioUnitDelay/wetDryMix)

The blend of the wet and dry signals.


---

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