Migrate from ElevenLabs

If your app already sends text to a provider and writes the returned audio to a file or stream, the migration is intentionally small: change the endpoint to Gradium, send your Gradium API key as x-api-key, and use a Gradium voice_id. The playback path can usually stay the same.

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Endpoint swap

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Request mapping

For POST requests, the most important change is that Gradium takes the voice in the JSON body instead of the URL path: Use the Gradium POST example as the replacement request. It returns raw audio bytes when only_audio is true, so existing “save the response body as audio” code can stay the same.

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WebSocket mapping

For streaming TTS, the Gradium lifecycle is:

1. Connect to wss://api.gradium.ai/api/speech/tts.
2. Send a setup message with voice_id, model_name, and output_format.
3. Send one or more text messages.
4. Send end_of_stream.
5. Read audio messages until Gradium sends end_of_stream.

Use the Gradium WebSocket example as the minimal replacement. Your receive loop should continue buffering audio chunks in the same place it buffered provider audio.

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Checklist

• Replace the provider URL with the Gradium endpoint.
• Change auth to x-api-key.
• Move the voice id from the URL path into voice_id.
• Use a Gradium voice id from the voice library.
• Keep your existing audio write/playback path.