Although singing and speech both involve the larynx and the vocal cords modulating air as it is pushed out of the lungs, they stem from different sides of the brain.

When we speak, the left-hand side is involved – the part that controls word formation and sentence structure. But when we sing, it is the right hemisphere that we rely upon, to produce the rhythm and melody of music.

So someone might have a speech impediment but it won't be there when they sing - because it's a different part of the brain. Even heavy regional accents are less apparent.

Singing seems simple, but it is actually an incredibly complicated motor activity. Like athletes, singers have to train their muscles, to project their voice in a certain way.

The muscles in the larynx contract to change the pitch of the voice, and good singers have a wonderful athletic ability to do that as well as an ear that is well tuned for sound.

Dr Gerald Brookes is a specialist in speech and voice and an ear, nose and throat surgeon at the Harley Street ENT clinic