# Update Speak

Voice Agent

The `UpdateSpeak` message is a JSON message that you can use to change the Speak model in the middle of a conversation.

## Purpose

The `UpdateSpeak` message is a JSON message that allows you to switch the Speak model during a conversation. This flexibility enables real-time adjustments to the agent's voice output, ensuring a more dynamic and responsive interaction tailored to the evolving needs of the conversation.

## Example Payloads

To send the `UpdateSpeak` message, you need to send the following JSON message to the server:

**`JSON`**

```json JSON
{
    "type": "UpdateSpeak",
    "speak": {
        "provider": {
            "type": "deepgram",
            "version": "v2",
            "model": "flux-alexis-en"
        }
    }
}
```

Upon receiving the `UpdateSpeak` message, the server will process all remaining audio data and return a [`SpeakUpdated`](/guides/self-hosted-deployments-3-voice-agent-acknowledgements#speakupdated) message.

:::callout{intent="info"}
With [Flux TTS](/guides/self-hosted-deployments-3-voice-agent-tts-models#flux-tts), the new voice takes effect on the agent's next turn — a turn already being spoken finishes in the voice that started it. `SpeakUpdated` confirms the change will be used; an update that cannot be applied returns an `Error` instead.
:::

**`JSON`**

```json JSON
{
    "type": "SpeakUpdated"
}
```

## Related pages

- [Inputs: Client Messages](./self-hosted-deployments-3-voice-agent-inputs.md)
- [Settings](./self-hosted-deployments-3-voice-agent-settings.md)
- [Update Listen](./self-hosted-deployments-3-voice-agent-update-listen.md)
- [Update Think](./self-hosted-deployments-3-voice-agent-update-think.md)
- [Update Prompt](./self-hosted-deployments-3-voice-agent-update-prompt.md)
- [Inject Agent](./self-hosted-deployments-3-voice-agent-inject-agent-message.md)
- [Inject User](./self-hosted-deployments-3-voice-agent-inject-user-message.md)
- [Force End Turn](./self-hosted-deployments-3-voice-agent-force-end-turn.md)
- [Agent Keep Alive](./self-hosted-deployments-3-agent-keep-alive.md)

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