title: Decrease bitrate on WAV file created with recorderjs
body: <p>I'm trying to use <a href="https://github.com/mattdiamond/Recorderjs">recorderjs</a> on an app engine site where users upload short audio recordings (say, 1 to a dozen seconds long). I've noticed that the WAV files I'm uploading are much larger than I expected. For example, I just created a recording that lasts roughly 9 seconds, and the uploaded blob is 1736769 bytes, which is > 1.5 megabytes.</p>
  
  <p><strong>Question:</strong> </p>
  
  <p>How do I modify the recorderjs code (or my own code -- maybe I'm using recorderjs incorrectly) so that my audio blobs have a lower bitrate?  I'd like a 10 second recording to be safely under 1 MB.</p>
  
  <p>My guess is that I would need to modify the encodeWAV function in <a href="https://github.com/mattdiamond/Recorderjs/blob/master/recorderWorker.js">here</a>, or maybe exportWAV, but I'm not sure how.  Would it make sense to just drop every other element of the interleaved buffer in exportWAV?  Is there a more intelligent way to do it?  How does the bitrate of the exported WAV depend on properties of my computer (e.g. the sampling rate of my soundcard)?</p>
  
  <p>I can add some details on my own code if it might be helpful.</p>
  
  <p>Edit: if you'd like to see a live example, install google chrome beta and try <a href="http://webaudiodemos.appspot.com/AudioRecorder/index.html">this page</a>. On my computer, a recording 5-10 seconds long is over 1 MB.</p>
  
  <p>Many thanks,</p>
  
  <p>Adrian</p>