> ## Documentation Index
> Fetch the complete documentation index at: https://developers.telnyx.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Voices

> Overview of voice providers, models, and selection syntax for Telnyx text-to-speech, including the voice query parameter and the provider/model/voice form.

Voices are specified via the `voice` query parameter or the separate `provider` + `model_id` + `voice_id` parameters. See [Parameters](/docs/voice/tts/websocket-streaming/parameters).

The format varies by provider — see each provider page for details.

## Providers

| Provider                                                              | Key                                                                                           | Audio Delivery              |
| --------------------------------------------------------------------- | --------------------------------------------------------------------------------------------- | --------------------------- |
| [Telnyx](/docs/voice/tts/voices/telnyx)                               | `telnyx`                                                                                      | Streamed (Ultra: REST only) |
| [Alternative Providers](/docs/voice/tts/voices/alternative-providers) | `aws`, `azure`, `elevenlabs`, `minimax`, `murfai`, `rime`, `resemble`, `inworld`, `fishaudio` | Varies                      |

<Info>
  **Streamed** providers send audio in incremental frames — the `audio` field on the text-bearing chunk is `null`. **Concatenated** providers return full audio in a single chunk.
</Info>