The Royal Albert Hall has unveiled a £2m speaker system designed to give the audience the same sound quality no matter where they are inside the auditorium.
It comprises 465 speakers and more than 15,000m (49,000ft) of cable.
It took 693 days to install, with most of the work carried out at night.
The last major improvement made to the hall’s acoustics was in 1969, when giant discs were attached to the ceiling.
The fibreglass “mushrooms”, as they became known, fixed an echo caused by the domed roof that had dogged the 148-year-old auditorium.
There are now speakers suspended from the ceiling all the way around the outside edge of the oval ceiling, as well as three speakers in each of the boxes that circle two tiers.
Detailed planning permission was required to make changes to the Grade I listed building in London.
The venue hosts hundreds of events every year, ranging from orchestral concerts and rock gigs to boxing matches and university graduations.
The speakers were deployed for the first time during concerts held by the Teenage Cancer Trust last week.
Gary Bradshaw, a sound engineer who has worked with Take That, Kylie Minogue and George Michael, said the new system had “greatly improved” the sound in the higher levels of the auditorium.
“The coverage was complete and the clarity and punch in all areas were impressive,” he said.
I went along to see UK band The Coral and moved around the hall during their performance, including the very top tier at the back, a box on the left-hand side and the main floor in the middle.
The sound was indeed similar from all three vantage points, although the beat was still only noticeably thumping through my feet on the ground floor, nearest to the band.
The newly equal sound would not signal the end of cheaper seating for those less close to the action, chief executive Craig Hassall told me.
“It’ll stop the complaints,” he said.
“It’s a concert hall first and foremost – the most important thing is how it sounds.”