"A duck's quack doesn't echo" is a much quoted scientific myth. In spring 2003 it was quoted on Home Truths on BBC Radio 4 and Shooting Stars on BBC 2. You can listen to our sound files on Home Truths by going to the BBC4 web site and "listening again". Recently, Salford Acoustics was the source of the story being presented in the national and international media when we proved that a duck's quack does echo as part of the British Association Festival of Science.

So what is an echo, and does it happen to a duck's quack?

Trevor and daisy (from right to left) © Manchester evening news