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# synthesizeSpeechRequest(_:)

Sets the text to synthesize and the voice to use.

```
func synthesizeSpeechRequest(_ speechRequest: AVSpeechSynthesisProviderRequest)
```

## Parameters

`speechRequest`

A speech request to synthesize.

## Discussion

When the synthesizer finishes generating audio buffers for the speech request, use <doc://com.apple.documentation/documentation/AudioToolbox/AUInternalRenderBlock> to report <doc://com.apple.documentation/documentation/AudioToolbox/AudioUnitRenderActionFlags/offlineUnitRenderAction_Complete>.

---

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