How can I get female voice by Web Speech API in Google Chrome

In a webpage, I want a female voice to speak my texts. I tried to do this by following code. But still now male voice is talking. How can I arrange a female voice to talk my texts? Can anybody share me a correct code that works in Google Chrome.

var voices = speechSynthesis.getVoices();
var msg = new SpeechSynthesisUtterance("Hello World!");
msg.default=false; 
msg.localservice=true;
msg.lang = "en-GB";
msg.voice = voices[3].name;
speechSynthesis.speak(msg);