Did you know that Guiness uses acoustics to create a perfect pint of their black stuff? The surger is a device, first launched in Tokyo, that send ultra-sonic waves through the drink allowing the dissolved gases to effervesce and is now used in bars across the world. The ultra-sonic waves passing through the Guinness is called initiation and causes bubbles to surge to the top of the glass creating the characteristic creamy head found in the traditional draught pint. The process and mathmatics behind the surger unit is complex, Guiness is dispensed with 21% carbon dioxide and 79% nitrogen which will not spontaneously foam, hence the need for a little ultra-sonic support from the ‘surger unit’ which introduces rectified diffusion, passive diffusion and convective diffusion – confused? yes, so are we. Better to drink the stuff and not to think too much about it!