title: How to reduce the size of the .wav file exported from Pydub
body: <p>When I do a conversion using ffmpeg, I am able to convert a 3.5MB mp3 file into an ~3.5MB wav file (using <code>ffmpeg -i input.mp3 -acodec pcm_s16le -ac 1 -ar 8000 output.wav</code>).
  When I use pydub however with the below code</p>
  
  <pre><code>s1 = AudioSegment.from_file("input.mp3", format="mp3")
  o1 = s1.export("output.wav",format="wav", parameters=["-acodec","pcm_s16le","-ac","1","-ar","8000"])
  </code></pre>
  
  <p>the exported wav file is 34.5MB.
  How can I get pydub to behave as expected?</p>