TTS.stream()

The stream() method is used to interact with the TTS model to produce an audio response stream. This method accepts text and voice as parameters.

Parameters

text:

string

The messages to be processed by TTS.

voice:

string

Voice ID to be used with generation.

Returns

audioResult?:

Readable

The generated audio stream

Examples

ElevenLabs Streaming

import { ElevenLabsTTS } from "@mastra/speech-elevenlabs";
 
const tts = new ElevenLabsTTS({
  model: {
    name: "eleven_multilingual_v2",
    apiKey: process.env.ELEVENLABS_API_KEY!,
  },
});
 
const voices = await tts.voices();
const voiceId = voices?.[0]?.voice_id!;
 
const { audioResult } = await tts.stream({
  text: "What is AI?",
  voice: voiceId,
});
 
// Create a write stream to simulate real-time playback
const outputPath = path.join(
  process.cwd(),
  "/test-outputs/streaming-output.mp3",
);
const writeStream = createWriteStream(outputPath);
 
let firstChunkTime: number | null = null;
let lastChunkTime: number | null = null;
let totalChunks = 0;
 
// Process chunks as they arrive
for await (const chunk of audioResult) {
  if (!firstChunkTime) {
    firstChunkTime = Date.now();
  }
  lastChunkTime = Date.now();
  totalChunks++;
 
  // Write chunk immediately as it arrives
  writeStream.write(chunk);
 
  // Log timing of chunk arrival
  console.log(
    `Received chunk ${totalChunks} at ${lastChunkTime - firstChunkTime!}ms`,
  );
}
 
writeStream.end();

OpenAI Streaming

import { OpenAITTS } from "@mastra/speech-openai";
 
const tts = new OpenAITTS({
  model: {
    name: "tts-1",
    apiKey: process.env.OPENAI_API_KEY!,
  },
});
 
const voices = await tts.voices();
const voiceId = voices?.[0]?.voice_id!;
 
const { audioResult } = await tts.stream({
  text: "What is AI?",
  voice: voiceId,
});
 
// Create a write stream to simulate real-time playback
const outputPath = path.join(
  process.cwd(),
  "/test-outputs/streaming-output.mp3",
);
const writeStream = createWriteStream(outputPath);
 
let firstChunkTime: number | null = null;
let lastChunkTime: number | null = null;
let totalChunks = 0;
 
// Process chunks as they arrive
for await (const chunk of audioResult) {
  if (!firstChunkTime) {
    firstChunkTime = Date.now();
  }
  lastChunkTime = Date.now();
  totalChunks++;
 
  // Write chunk immediately as it arrives
  writeStream.write(chunk);
 
  // Log timing of chunk arrival
  console.log(
    `Received chunk ${totalChunks} at ${lastChunkTime - firstChunkTime!}ms`,
  );
}
 
writeStream.end();

PlayAI Streaming

import { PlayAITTS } from "@mastra/speech-playai";
 
const tts = new PlayAITTS({
  model: {
    name: "PlayDialog",
    apiKey: process.env.PLAYAI_API_KEY!,
  },
  userId: process.env.PLAYAI_USER_ID!,
});
 
const voices = await tts.voices();
const voiceId = voices?.[0]?.voice_id!;
 
const { audioResult } = await tts.stream({
  text: "What is AI?",
  voice: voiceId,
});
 
// Create a write stream to simulate real-time playback
const outputPath = path.join(
  process.cwd(),
  "/test-outputs/streaming-output.mp3",
);
const writeStream = createWriteStream(outputPath);
 
let firstChunkTime: number | null = null;
let lastChunkTime: number | null = null;
let totalChunks = 0;
 
// Process chunks as they arrive
for await (const chunk of audioResult) {
  if (!firstChunkTime) {
    firstChunkTime = Date.now();
  }
  lastChunkTime = Date.now();
  totalChunks++;
 
  // Write chunk immediately as it arrives
  writeStream.write(chunk);
 
  // Log timing of chunk arrival
  console.log(
    `Received chunk ${totalChunks} at ${lastChunkTime - firstChunkTime!}ms`,
  );
}
 
writeStream.end();

Azure Streaming

import { AzureTTS } from "@mastra/speech-azure";
 
const tts = new AzureTTS({
  model: {
    name: "en-US-JennyNeural",
    apiKey: process.env.AZURE_API_KEY,
    region: process.env.AZURE_REGION,
  },
});
 
const { audioResult } = await tts.stream({ text: "What is AI?" });
 
// Create a write stream
const outputPath = path.join(process.cwd(), "/test-outputs/azure-stream.mp3");
const writeStream = createWriteStream(outputPath);
 
// Pipe the audio stream to the file
audioResult.pipe(writeStream);

Deepgram Streaming

import { DeepgramTTS } from "@mastra/speech-deepgram";
 
const tts = new DeepgramTTS({
  model: {
    name: "aura",
    voice: "asteria-en",
    apiKey: process.env.DEEPGRAM_API_KEY,
  },
});
 
const { audioResult } = await tts.stream({ text: "What is AI?" });
 
// Create a write stream
const outputPath = path.join(
  process.cwd(),
  "/test-outputs/deepgram-stream.mp3",
);
const writeStream = createWriteStream(outputPath);
 
// Pipe the audio stream to the file
audioResult.pipe(writeStream);

Google Streaming

import { GoogleTTS } from "@mastra/speech-google";
 
const tts = new GoogleTTS({
  model: {
    name: "en-US-Standard-A",
    credentials: process.env.GOOGLE_CREDENTIALS,
  },
});
 
const { audioResult } = await tts.stream({ text: "What is AI?" });
 
// Create a write stream
const outputPath = path.join(process.cwd(), "/test-outputs/google-stream.mp3");
const writeStream = createWriteStream(outputPath);
 
// Pipe the audio stream to the file
audioResult.pipe(writeStream);

IBM Streaming

import { IbmTTS } from "@mastra/speech-ibm";
 
const tts = new IbmTTS({
  model: {
    voice: "en-US_AllisonV3Voice",
    apiKey: process.env.IBM_API_KEY,
  },
});
 
const { audioResult } = await tts.stream({ text: "What is AI?" });
 
// Create a write stream
const outputPath = path.join(process.cwd(), "/test-outputs/ibm-stream.mp3");
const writeStream = createWriteStream(outputPath);
 
// Pipe the audio stream to the file
audioResult.pipe(writeStream);

Murf Streaming

import { MurfTTS } from "@mastra/speech-murf";
 
const tts = new MurfTTS({
  model: {
    name: "GEN2",
    voice: "en-US-natalie",
    apiKey: process.env.MURF_API_KEY,
  },
});
 
const { audioResult } = await tts.stream({ text: "What is AI?" });
 
// Create a write stream
const outputPath = path.join(process.cwd(), "/test-outputs/murf-stream.mp3");
const writeStream = createWriteStream(outputPath);
 
// Pipe the audio stream to the file
audioResult.pipe(writeStream);

.generate()LibSQL Storage