How loud is your advert?

Television channels are footing the bill for new technology to prove that advertisements really are louder than programmes. For more than 35 years viewers have complained about the irritating ploys of advertisers, who use cunning audio trickery to grab attention.

Although TV advertisements are not higher in volume than programmes, they appear louder because of the way the sound is compressed and filtered.

Engineers began tackling the problem after a Broadcast Audience Research Board survey of 3,000 viewers in 1993 found that "substantial proportions" thought commercials were too loud.

Two years ago, John Emmett, research and development manager of Pearson Television, began to develop a loudness meter. His final design has already been ordered by Channel 4, and both the BBC and ITV have begun evaluating the technology, New Scientist magazine reported yesterday.