Streaming TTS

synthesizeStream emits AudioChunk values as they are produced, so playback starts on the first chunk instead of the last.

for await (const chunk of RunAnywhere.tts.synthesizeStream(longText)) {
  player.enqueue(chunk)
}

Signature

synthesizeStream(text: string, options?: TtsOptions): AsyncIterableIterator<AudioChunk>

When it is worth it

For a sentence, speak is simpler and the latency difference is invisible. For a paragraph, or for a model reply being streamed as it generates, streaming synthesis is what keeps the gap between “the model finished” and “the user hears something” short.

Pairing it with a streaming completion

Speak each sentence as the model finishes it:

let sentence = ''

for await (const event of RunAnywhere.llm.generateStream(prompt)) {
  if (event.type !== 'textDelta') continue
  sentence += event.text

  if (/[.!?]/.test(event.text)) {
    await RunAnywhere.tts.speak(sentence)
    sentence = ''
  }
}

if (sentence) await RunAnywhere.tts.speak(sentence)

For a full conversation rather than one reply, use the voice session, which handles turn-taking and interruption.

Forwarding chunks to the renderer

When the audio graph lives in the window, send chunks as they arrive rather than buffering the whole utterance in the main process:

for await (const chunk of RunAnywhere.tts.synthesizeStream(text)) {
  win.webContents.send('audio-chunk', chunk)
}

Audio chunks are much larger than text deltas, so batching matters here in a way it does not for tokens. Send each chunk once and let the renderer schedule them against a running clock.

Stopping

await RunAnywhere.tts.stop()

Getting Started

Swift SDK

Kotlin SDK

React Native SDK

Flutter SDK

Web SDK

Electron SDK

Vibe Coding

Signature

When it is worth it

Pairing it with a streaming completion

Forwarding chunks to the renderer

Stopping

​Signature

​When it is worth it

​Pairing it with a streaming completion

​Forwarding chunks to the renderer

​Stopping

Signature

When it is worth it

Pairing it with a streaming completion

Forwarding chunks to the renderer

Stopping