Finger nails scrapping down a blackboard, the scream of a baby, your neighbour’s dog barking, someone throwing up: what is the worst sound in the world? In 2005/6 I ran a large scale web experiment to examine the worst sound in the world which attracted millions of votes. While the website has produced interesting results on people’s responses to the sounds, it is still unclear how valid the results are? In this phd research project, you will carry out perceptual measurements in the laboratory to compare to web experiment results, to determine the limitations of testing subjective responses over the Internet. Can the vast number of respondents available via the Internet compensate for the very uncontrolled experimental conditions?