title: Web Audio: How can I get a mobile microphone to pick up audio from a distance?
body: <p>Getting access to the user's microphone through <code>navigator.getUserMedia</code> is pretty easy.  But what if I'm using a mobile browser and want to pick up audio from a distance, like with a "speakerphone" mode?</p>
  
  <p>How would I go about achieving this?  There seem to be native apps that can achieve this, but what about Web Audio?</p>
  
  <p>The purpose of this is for sending messages between devices using DTMF.  I have already achieved this with my laptop because its microphone can record surrounding audio from a great distance, but any mobile phone I have access to seems to only record audio near the "mouthpiece" and so I have to hold the phone extremely close to the source speaker for even a slight chance of having a message received.  This defeats the purpose unless I can get the mobile microphone to pick up audio from a distance.</p>
  
  <p>EDIT: By distance, I mean greater than a few feet, as opposed to mere centimeters.  Ambient sounds, as opposed to sound localized next to the microphone.</p>