Stream speech

Convert text to speech with streaming response

curl --request POST \
  --url https://supertoneapi.com/v1/text-to-speech/{voice_id}/stream \
  --header 'Content-Type: application/json' \
  --header 'x-sup-api-key: <api-key>' \
  --data '
{
  "text": "<string>",
  "style": "<string>",
  "model": "sona_speech_1",
  "output_format": "wav",
  "voice_settings": {
    "pitch_shift": 0,
    "pitch_variance": 1,
    "speed": 1,
    "duration": 0,
    "similarity": 3,
    "text_guidance": 1,
    "subharmonic_amplitude_control": 1
  },
  "include_phonemes": false,
  "normalized_text": "<string>"
}
'

import requests

url = "https://supertoneapi.com/v1/text-to-speech/{voice_id}/stream"

payload = {
    "text": "<string>",
    "style": "<string>",
    "model": "sona_speech_1",
    "output_format": "wav",
    "voice_settings": {
        "pitch_shift": 0,
        "pitch_variance": 1,
        "speed": 1,
        "duration": 0,
        "similarity": 3,
        "text_guidance": 1,
        "subharmonic_amplitude_control": 1
    },
    "include_phonemes": False,
    "normalized_text": "<string>"
}
headers = {
    "x-sup-api-key": "<api-key>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {'x-sup-api-key': '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    text: '<string>',
    style: '<string>',
    model: 'sona_speech_1',
    output_format: 'wav',
    voice_settings: {
      pitch_shift: 0,
      pitch_variance: 1,
      speed: 1,
      duration: 0,
      similarity: 3,
      text_guidance: 1,
      subharmonic_amplitude_control: 1
    },
    include_phonemes: false,
    normalized_text: '<string>'
  })
};

fetch('https://supertoneapi.com/v1/text-to-speech/{voice_id}/stream', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://supertoneapi.com/v1/text-to-speech/{voice_id}/stream"

	payload := strings.NewReader("{\n  \"text\": \"<string>\",\n  \"style\": \"<string>\",\n  \"model\": \"sona_speech_1\",\n  \"output_format\": \"wav\",\n  \"voice_settings\": {\n    \"pitch_shift\": 0,\n    \"pitch_variance\": 1,\n    \"speed\": 1,\n    \"duration\": 0,\n    \"similarity\": 3,\n    \"text_guidance\": 1,\n    \"subharmonic_amplitude_control\": 1\n  },\n  \"include_phonemes\": false,\n  \"normalized_text\": \"<string>\"\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("x-sup-api-key", "<api-key>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://supertoneapi.com/v1/text-to-speech/{voice_id}/stream",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'text' => '<string>',
    'style' => '<string>',
    'model' => 'sona_speech_1',
    'output_format' => 'wav',
    'voice_settings' => [
        'pitch_shift' => 0,
        'pitch_variance' => 1,
        'speed' => 1,
        'duration' => 0,
        'similarity' => 3,
        'text_guidance' => 1,
        'subharmonic_amplitude_control' => 1
    ],
    'include_phonemes' => false,
    'normalized_text' => '<string>'
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "x-sup-api-key: <api-key>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

HttpResponse<String> response = Unirest.post("https://supertoneapi.com/v1/text-to-speech/{voice_id}/stream")
  .header("x-sup-api-key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"text\": \"<string>\",\n  \"style\": \"<string>\",\n  \"model\": \"sona_speech_1\",\n  \"output_format\": \"wav\",\n  \"voice_settings\": {\n    \"pitch_shift\": 0,\n    \"pitch_variance\": 1,\n    \"speed\": 1,\n    \"duration\": 0,\n    \"similarity\": 3,\n    \"text_guidance\": 1,\n    \"subharmonic_amplitude_control\": 1\n  },\n  \"include_phonemes\": false,\n  \"normalized_text\": \"<string>\"\n}")
  .asString();

"<string>"

{
  "status": "error",
  "message": "Invalid request data"
}

{
  "status": "error",
  "message": {
    "message": "Invalid API Key",
    "error": "Unauthorized"
  }
}

{
  "status": "error",
  "message": {
    "message": "Not enough credits",
    "error": "Payment Required"
  }
}

{
  "status": "error",
  "message": {
    "message": "Permission denied",
    "error": "Forbidden"
  }
}

{
  "status": "error",
  "message": {
    "message": "Voice not found",
    "error": "Not Found"
  }
}

{
  "status": "error",
  "message": {
    "message": "Request timed out",
    "error": "Request Timeout"
  }
}

{
  "status": "error",
  "message": {
    "message": "rate limit exceeded",
    "error": "Too Many Requests"
  }
}

{
  "status": "error",
  "message": {
    "message": "Failed to convert text to speech",
    "error": "Internal Server Error"
  }
}

POST

text-to-speech

{voice_id}

stream

Convert text to speech with streaming response

curl --request POST \
  --url https://supertoneapi.com/v1/text-to-speech/{voice_id}/stream \
  --header 'Content-Type: application/json' \
  --header 'x-sup-api-key: <api-key>' \
  --data '
{
  "text": "<string>",
  "style": "<string>",
  "model": "sona_speech_1",
  "output_format": "wav",
  "voice_settings": {
    "pitch_shift": 0,
    "pitch_variance": 1,
    "speed": 1,
    "duration": 0,
    "similarity": 3,
    "text_guidance": 1,
    "subharmonic_amplitude_control": 1
  },
  "include_phonemes": false,
  "normalized_text": "<string>"
}
'

import requests

url = "https://supertoneapi.com/v1/text-to-speech/{voice_id}/stream"

payload = {
    "text": "<string>",
    "style": "<string>",
    "model": "sona_speech_1",
    "output_format": "wav",
    "voice_settings": {
        "pitch_shift": 0,
        "pitch_variance": 1,
        "speed": 1,
        "duration": 0,
        "similarity": 3,
        "text_guidance": 1,
        "subharmonic_amplitude_control": 1
    },
    "include_phonemes": False,
    "normalized_text": "<string>"
}
headers = {
    "x-sup-api-key": "<api-key>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {'x-sup-api-key': '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    text: '<string>',
    style: '<string>',
    model: 'sona_speech_1',
    output_format: 'wav',
    voice_settings: {
      pitch_shift: 0,
      pitch_variance: 1,
      speed: 1,
      duration: 0,
      similarity: 3,
      text_guidance: 1,
      subharmonic_amplitude_control: 1
    },
    include_phonemes: false,
    normalized_text: '<string>'
  })
};

fetch('https://supertoneapi.com/v1/text-to-speech/{voice_id}/stream', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://supertoneapi.com/v1/text-to-speech/{voice_id}/stream"

	payload := strings.NewReader("{\n  \"text\": \"<string>\",\n  \"style\": \"<string>\",\n  \"model\": \"sona_speech_1\",\n  \"output_format\": \"wav\",\n  \"voice_settings\": {\n    \"pitch_shift\": 0,\n    \"pitch_variance\": 1,\n    \"speed\": 1,\n    \"duration\": 0,\n    \"similarity\": 3,\n    \"text_guidance\": 1,\n    \"subharmonic_amplitude_control\": 1\n  },\n  \"include_phonemes\": false,\n  \"normalized_text\": \"<string>\"\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("x-sup-api-key", "<api-key>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://supertoneapi.com/v1/text-to-speech/{voice_id}/stream",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'text' => '<string>',
    'style' => '<string>',
    'model' => 'sona_speech_1',
    'output_format' => 'wav',
    'voice_settings' => [
        'pitch_shift' => 0,
        'pitch_variance' => 1,
        'speed' => 1,
        'duration' => 0,
        'similarity' => 3,
        'text_guidance' => 1,
        'subharmonic_amplitude_control' => 1
    ],
    'include_phonemes' => false,
    'normalized_text' => '<string>'
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "x-sup-api-key: <api-key>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

HttpResponse<String> response = Unirest.post("https://supertoneapi.com/v1/text-to-speech/{voice_id}/stream")
  .header("x-sup-api-key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"text\": \"<string>\",\n  \"style\": \"<string>\",\n  \"model\": \"sona_speech_1\",\n  \"output_format\": \"wav\",\n  \"voice_settings\": {\n    \"pitch_shift\": 0,\n    \"pitch_variance\": 1,\n    \"speed\": 1,\n    \"duration\": 0,\n    \"similarity\": 3,\n    \"text_guidance\": 1,\n    \"subharmonic_amplitude_control\": 1\n  },\n  \"include_phonemes\": false,\n  \"normalized_text\": \"<string>\"\n}")
  .asString();

"<string>"

{
  "status": "error",
  "message": "Invalid request data"
}

{
  "status": "error",
  "message": {
    "message": "Invalid API Key",
    "error": "Unauthorized"
  }
}

{
  "status": "error",
  "message": {
    "message": "Not enough credits",
    "error": "Payment Required"
  }
}

{
  "status": "error",
  "message": {
    "message": "Permission denied",
    "error": "Forbidden"
  }
}

{
  "status": "error",
  "message": {
    "message": "Voice not found",
    "error": "Not Found"
  }
}

{
  "status": "error",
  "message": {
    "message": "Request timed out",
    "error": "Request Timeout"
  }
}

{
  "status": "error",
  "message": {
    "message": "rate limit exceeded",
    "error": "Too Many Requests"
  }
}

{
  "status": "error",
  "message": {
    "message": "Failed to convert text to speech",
    "error": "Internal Server Error"
  }
}

Streams generated speech back chunk-by-chunk so you can start playback before the full clip is ready. For when to use streaming versus a fast non-streaming model, see Docs: Stream speech and Latency optimization.

Streaming is currently supported on sona_speech_1 only.

Endpoint

POST https://supertoneapi.com/v1/text-to-speech/{voice_id}/stream

Path parameters

Name	Required	Description
`voice_id`	✅	The ID of the target voice.

Request body

Content-Type: application/json

Name	Required	Description
`text`	✅	The text to convert. Max 300 characters.
`language`	✅	Language code. Supported: `en`, `ko`, `ja`.
`style`	—	Emotional style (e.g. `neutral`, `happy`). If omitted, the voice’s default style is used.
`model`	—	Must be `sona_speech_1` (the only model that supports streaming).
`output_format`	—	`wav` (default) or `mp3`.
`voice_settings`	—	Advanced voice parameters — same fields and ranges as Create speech.
`include_phonemes`	—	If `true`, response is NDJSON with phoneme data per chunk. Default: `false`.

Response

Default (include_phonemes=false): Binary audio stream.

Content-Type: audio/wav or audio/mpeg (matches output_format).
The first chunk includes the audio file header; subsequent chunks are raw audio data.

When include_phonemes=true: Newline-delimited JSON (NDJSON), one object per chunk:

{"audio_base64":"...","phonemes":{"symbols":["","h"],"start_times_seconds":[0,0.05],"durations_seconds":[0.05,0.08]}}
{"audio_base64":"...","phonemes":{"symbols":["ɐ","ɡ"],"start_times_seconds":[0.13,0.19],"durations_seconds":[0.06,0.04]}}

Notes

Stream speech is currently in beta and supports only sona_speech_1.
text over 300 characters returns 400. SDKs auto-chunk longer input and forward chunks to your iterator.
speed applies after duration (e.g. duration=5 + speed=2 ≈ 10 seconds).
When style is omitted, the voice’s default style is used. Use Get voice to inspect defaults.

Docs: Stream speech

When to stream and how to consume chunks in each SDK.

LLM streaming TTS

End-to-end recipes with OpenAI and Anthropic.

Authorizations

x-sup-api-key

string

header

required

Path Parameters

voice_id

string

required

Body

application/json

text

string

required

The text to convert to speech

Maximum string length: 300

language

enum<string>

required

The language code of the text

Available options:

en,

ko,

ja,

bg,

cs,

da,

el,

es,

et,

fi,

hu,

it,

nl,

pl,

pt,

ro,

ar,

de,

fr,

hi,

id,

ru,

vi,

hr,

lt,

lv,

sk,

sl,

sv,

tr,

uk

style

string

The style of character to use for the text-to-speech conversion

model

enum<string>

default:sona_speech_1

The model type to use for the text-to-speech conversion

Available options:

sona_speech_1,

sona_speech_2,

sona_speech_2_flash,

supertonic_api_1,

supertonic_api_3

output_format

enum<string>

default:wav

The desired output format of the audio file (wav, mp3). Default is wav.

Available options:

wav,

mp3

voice_settings

object

Show child attributes

include_phonemes

boolean

default:false

Return phoneme timing data with the audio

normalized_text

string

Pre-normalized text for TTS. Only used with sona_speech_2 and sona_speech_2_flash models.

Response

Streaming audio data in binary format or NDJSON format with phoneme data based on includePhonemes parameter

Binary audio stream (when includePhonemes=false or omitted)

⌘I

Supertone API

Voices

Custom voices

Text to speech

Usage

Endpoint

Path parameters

Request body

Response

Notes

See also

Docs: Stream speech

LLM streaming TTS

Authorizations

Path Parameters

Body

Response

​Endpoint

​Path parameters

​Request body

​Response

​Notes

​See also

Docs: Stream speech

LLM streaming TTS

Authorizations

Path Parameters

Body

Response

Endpoint

Path parameters

Request body

Response

Notes

See also