Stream Speech to Speech

POST 
https://api.knoxstudio.ai/v1/speech-to-speech/:voice_id/stream

Same multipart body as Convert speech to speech, but audio is streamed. WAV output_format values are not allowed.

Request

Path Parameters

Name	Type	Required	Description
voice_id	String	Yes	Target ElevenLabs voice ID.

Query Parameters

Name	Type	Required	Description
output_format	String	No	WAV is not allowed. Allowed: mp3_22050_32, mp3_24000_48, mp3_44100_32, mp3_44100_64, mp3_44100_96, mp3_44100_128, mp3_44100_192, pcm_8000, pcm_16000, pcm_22050, pcm_24000, pcm_32000, pcm_44100, pcm_48000, ulaw_8000, alaw_8000, opus_48000_32, opus_48000_64, opus_48000_96, opus_48000_128, opus_48000_192. WAV is not allowed.
enable_logging	Boolean	No	Default true. false requests zero-retention mode.
optimize_streaming_latency	Integer	No	Deprecated. 0–4 latency/quality tradeoff.

Request Headers

Name	Type	Required	Description
Authorization	String	Yes	Bearer <token> Knox API key. xi-api-key is also accepted.
Content-Type	String	Yes	multipart/form-data

Request Body

Name	Type	Required	Description
audio	File	Yes	Source audio that supplies content and emotion.
model_id	String	No	eleven_multilingual_sts_v2 (default) or eleven_english_sts_v2. TTS IDs are rejected.
file_format	String	No	pcm_s16le_16 or other.
seed	Integer	No	0–4294967295. Best-effort determinism.
voice_settings	String (JSON object)	No	JSON-encoded object, for example stability / similarity_boost.
remove_background_noise	Boolean	No	true / false / 1 / 0. Isolates speech before conversion.

cURL Example

curl -X POST "https://api.knoxstudio.ai/v1/speech-to-speech/21m00Tcm4TlvDq8ikWAM/stream?output_format=mp3_44100_128" \
     -H "Authorization: Bearer $KNOXCHAT_API_KEY" \
     -F "audio=@speech.wav" \
     -F "model_id=eleven_multilingual_sts_v2" \
     -o changed.mp3

Response

Success Response (200)

Streaming converted audio bytes.

Error Responses

Validation uses HTTP 422:

{
  "detail": [
    {
      "loc": ["body", "field"],
      "msg": "…",
      "type": "value_error"
    }
  ]
}

Other errors use { "detail": "message" }.

Status	When
400	WebSocket path called without Upgrade: websocket.
401	Missing or invalid API key.
402	Insufficient credits.
403	Token is not allowed to use this model.
404	Resource not found.
422	Validation error.
429	Rate limit exceeded.
500	Internal server error.