Audio experts call for caution

The programme attracted 100 complaints from viewers who said that presenter Brian Cox’s narrative had been reduced to “a whisper” because of excessively loud background music.

It prompted the BBC to bring forward the publication of guidelines for the use of sound, including the suggestion that music be reduced by 4dB on all shows.

Hackenbacker managing director and re-recording mixer Nigel Heath warned against a hurried response: “In well-mixed programmes, dropping by 4dB will become a serious creative issue.

“Some superb work is currently airing and it is wrong to suggest a global reduction in music levels because of this.”

Aquarium owner and sound supervisor Ben Baird said that if the BBC proposals were adopted, facilities might simply mix the programme 4dB higher in anticipation, as sometimes happens in cinema.

“It seems too broad a stroke to cure audibility problems that are more complicated than simply the music being too loud,” he said.

Baird added that while the UK has “many talented sound experts” there needs to be a greater emphasis on training.

“The industry has slowed down on education so now we are reaping that harvest, with an under-trained generation.”

Halo managing director John Rogerson, speaking generally about the sound sector, said: “The quality of the mix is down to the skill of the mixer. It’s a painstaking job to get everything in the right place and still clearly audible.”

The BBC’s recommendations for post facilities include the recording of “clean” voiceovers and the “considered” use of music, particularly percussive beats or lyrics that are placed under dialogue.

The broadcaster also advised post facilities to listen to the mix on TV speakers “in order to know how the listening experience will be for the audience”.

Rogerson agreed: “A mixer should be optimising the audio content for the weakest point in the delivery system, which is essentially a bog-standard telly speaker.”