text:  Up next on the BBC World Service, it's the Outlook mixtape, spooling through some of our favourite stories from the week. Where else could you learn how to growl like a heavy metal star? It's like when you sigh, like the hmm, at the end of the sigh, hmm. But now you just hold it and you push it from the diaphragm. You can shape it in different things. You can do inhales. Brrrr.