tested on osx/chrome, works really good with the Utterance set to rate = 1; pitch = 0.01; msg.lang = 'en'; msg.voice ="Google UK English Male"<p>you can visit a served version of the gist here:
<a href="https://gistpreview.github.io/?1d3520da4ee0f91f835307b2c1d199de/whisper_web_speech.html" rel="nofollow">https://gistpreview.github.io/?1d3520da4ee0f91f835307b2c1d19...</a>