,
  password: '&lt;password>',
  version: 'v1'
});

var params = {
  text: 'Hello from IBM Watson',
  voice: 'en-US_AllisonVoice', // Optional voice
  accept: 'audio/wav'
};

// Pipe the synthesized text to a file
text_to_speech.synthesize(params).pipe(fs.createWriteStream('output.wav'));</code></pre><h3>Tone Analyzer</h3><p>Use the <a href="http://www.ibm.com/watson/developercloud/tone-analyzer.html">Tone Analyzer</a> service to analyze the
emotion, writing and social tones of a text.</p>
<pre class="prett