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Gradium Speech-to-Speech (S2S) translates spoken audio from one language into spoken audio in another, over a single duplex WebSocket. The input audio is transcribed, translated into the target language, and re-synthesized as output audio. You stream audio in and receive both the synthesized output audio and the translated transcript back as they’re produced.

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Model

The only currently supported S2S model is live translation. To use it, send a setup message with model_name set to "s2s-translate", stt_model_name set to "stt-translate", and tts_model_name set to "default". Choose the target language with target_language in json_config, and the output voice with voice_id (required; it must be a voice in the target language). 
{
  "type": "setup",
  "model_name": "s2s-translate",
  "stt_model_name": "stt-translate",
  "tts_model_name": "default",
  "input_format": "pcm",
  "output_format": "pcm",
  "voice_id": "YTpq7expH9539ERJ",
  "json_config": { "target_language": "en" }
}
For the full list of fields and formats, see Speech-to-Speech Settings.

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Next steps

Use the WebSocket API

Stream audio in, output audio and transcript out, real-time or buffered.

S2S settings

voice_id, target_language, inner model selection, formats.

S2S WebSocket reference

Complete wire-level schema: every message type, every field, every error code.

Voices

Pick the voice used for the synthesized output.