Hi everyone, I'm curious about getting a Guinness-like head on some beer. Firstly Ive already read that N2O nitrous-oxide is not what is needed but rather pure N2 nitrogen. I'm a bit confused, because I have read that nitrogen is basically not water soluble and so the purpose is not to make beer fizzy, but simply to provide serving pressure for tap lines with low carbonation beer and the head comes from feeding the beer through a diffuser plate. However the Guinness draft cans have a widget in them which I believe is N2 and there is certianly no diffuser plate! Same with John Smiths type beer. Yet they still achieve creamy stable head. So something doesn't add up for me. What's the real story here?? What does N2 contribute to stable small bubbles head?