Ultra-quiet hair dryer.Published 28/04/2016 | 02:30The tech that everyone"s talking about this week is a new hair dryer from Dyson - and it will appeal to those who like the silent treatment.The Supersonic is light, colourful and cuts down on noise. The device, which cost 50m and three years to develop, boasts a new type of digital motor which has pushed noise to a sound frequency "beyond the audible range for humans".Its...