In case you'd like to know what they all sound like (there's a bunch of funny ones)
var pack_msg = (v, i) => { return { voice: v, text: `hi there from the voice named ${v.name}` }; },
    msgs     = speechSynthesis.getVoices().map(pack_msg),
    speaker  = new SpeechSynthesisUtterance(),
    halt     = false;