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

# Model selection

The `speech_model` connection parameter lets you specify which model to use for streaming transcription. It's optional; if omitted, the session defaults to `universal-3-6-pro`.

## Available models

| Name | Parameter | Description | Best for |
| - | - | - | - |
| **Universal-3.6 Pro Streaming** <span class="recommended-pill">Recommended</span> | `"universal-3-6-pro"` | Our flagship streaming model. 32 languages with native code-switching, plus prompting and conversational context features. | Real-time voice agents needing the latest accuracy, broad language support, and conversational context. |
| **Universal-3.5 Pro Streaming** | `"universal-3-5-pro"` | The previous flagship streaming model. Still fully supported, with the same features as Universal-3.6 Pro but 19 languages instead of 32. | Existing integrations pinned to this model. |
| **Universal-Streaming English** | `"universal-streaming-english"` | An English transcription model offering a good balance of speed and cost-effectiveness. | Cost-effective English real-time transcription, English-only real-time apps |
| **Universal-Streaming Multilingual** | `"universal-streaming-multilingual"` | A multilingual transcription model offering a good balance of speed and cost-effectiveness. | Cost-effective multilingual streaming across EN/ES/DE/FR/PT/IT |

## Choosing a model

| Feature | Universal-3.6 Pro / 3.5 Pro Streaming <span class="recommended-pill">Recommended</span> | Universal-Streaming English | Universal-Streaming Multilingual |
| - | - | - | - |
| **Latency** | Fastest | Fast | Fast |
| **Supported languages** | 32 on Universal-3.6 Pro, 19 on Universal-3.5 Pro ([full list](/docs/streaming/multilingual-transcription#supported-languages)) | EN | EN, ES, DE, FR, PT, IT |
| **Partial transcripts** | Yes | Yes | Yes |
| **Multilingual** | Native Code Switching | No | Per Turn |
| **Entity accuracy** | Best | Okay | Okay |
| **Disfluencies & filler words** | Yes | No | No |
| **Language detection** | Yes | No | Yes |
| **Non-speech tags** | No | No | No |
| **Customization** | [Keyterms prompting](/docs/streaming/prompting-and-keyterms) (known context) + [Native prompting](/docs/streaming/prompting-and-keyterms) (unknown context) | [Keyterms prompting](/docs/streaming/prompting-and-keyterms) (known context) | [Keyterms prompting](/docs/streaming/prompting-and-keyterms) (known context) |

For detailed setup and configuration of Universal-3.6 Pro Streaming, see the [Universal-3.6 Pro Streaming](/docs/streaming/getting-started/transcribe-streaming-audio) page. For prompting guidance, see the [Prompting guide](/docs/streaming/prompting-and-keyterms).

## Set the model

Set the `speech_model` connection parameter when you open the WebSocket.

<Tabs>
  <Tab language="python" title="Python" default>
    ```python theme={null}
    CONNECTION_PARAMS = {
        "sample_rate": 16000,
        "speech_model": "universal-3-6-pro",  # universal-3-5-pro | universal-streaming-english | universal-streaming-multilingual
    }
    ```
  </Tab>

  <Tab language="python-sdk" title="Python SDK">
    ```python theme={null}
    client.connect(
        RealTimeParameters(
            sample_rate=16000,
            speech_model="universal-3-6-pro",  # universal-3-5-pro | universal-streaming-english | universal-streaming-multilingual
        )
    )
    ```
  </Tab>

  <Tab language="javascript" title="Javascript">
    ```javascript theme={null}
    const CONNECTION_PARAMS = {
      sample_rate: 16000,
      speech_model: "universal-3-6-pro", // universal-3-5-pro | universal-streaming-english | universal-streaming-multilingual
    };
    ```
  </Tab>

  <Tab language="javascript-sdk" title="JavaScript SDK">
    ```javascript theme={null}
    const transcriber = client.streaming.transcriber({
      sampleRate: 16_000,
      speechModel: "universal-3-6-pro", // universal-3-5-pro | universal-streaming-english | universal-streaming-multilingual
    });
    ```
  </Tab>
</Tabs>