# March 26, 2026

## TTS speed controls & updated LLM models

### TTS speak speed (Early Access)

You can now control the speaking rate of Deepgram TTS in the Voice Agent API using the `agent.speak.provider.speed` parameter. This parameter accepts a float value between `0.7` and `1.5`, with `1.0` as the default.

```json
{
  "type": "Settings",
  "agent": {
    "speak": {
      "provider": {
        "type": "deepgram",
        "model": "aura-2-thalia-en",
        "speed": 0.9
      }
    }
  }
}
```

This feature is in Early Access and is only available for Deepgram TTS. For more details, see [TTS voice controls](/guides/tts-voice-controls-tts-voice-controls#parameters). To request access, contact your Account Executive or reach out to sales@deepgram.com.

### Updated LLM models

**New OpenAI models** — Two new models are now available in the Standard pricing tier:

- `gpt-5.4-nano`
- `gpt-5.4-mini`

**Gemini 2.0 Flash deprecated** — The `gemini-2.0-flash` model is now deprecated. We recommend migrating to `gemini-2.5-flash` or a newer Gemini model. See the [Google models table](/guides/self-hosted-deployments-3-voice-agent-llm-models#google) for alternatives.

For the full list of supported models and pricing tiers, see the [Voice Agent LLM Models documentation](/guides/self-hosted-deployments-3-voice-agent-llm-models).

## Related pages

- [Amazon SageMaker](./amazon-sagemaker-index.md)
- [Aura](./aura-index.md)
- [Changelog](../changelog.md)
- [Custom Vocabulary](./custom-vocabulary-index.md)
- [Deepgram's Docs](../index.md)
- [Deployment](./deployment-index.md)
- [Docker/Podman](./docker-podman-index.md)
- [Features](./features-index.md)
- [Flux TTS](./flux-tts-index.md)
- [Formatting](./formatting-index.md)

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