How Does Big Ben Bong?

Using lasers, scientists have analysed how the sound of Big Ben’s bongs is created.

18:08 08 March 2017

In a study commissioned by the BBC, scientists have analysed how the sound of Big Ben’s bongs is created using lasers. The findings, which will be featured in the BBC Four series Sound Waves: The Symphony of Physics, explain the technical aspects of how the Great Bell produces its harmonious tone.

 

The team of scientists was granted exclusive access in the belfry of Elizabeth Tower at the Palace of Westminster. They used two lasers to scan Big Ben as it chimed at 9, 10, 11 and 12 o’clock.

 

Head researcher Martin Cockrill, from the University of Leicester, revealed that the project was challenging.

 

He said: "Aside from the technical aspects, one of the most challenging parts of the job was carrying all of our equipment up the 334 steps of the spiral staircase to the belfry,"

 

"Then to get everything set up before the first chime, we were literally working against the clock."

 

As for their findings, he shared:  "Many of the vibrations in the metal of Big Ben are too tiny to be seen by the naked eye. But this is what we were able to map using the lasers and not just one or two points on the surface; we were able to get over 500 measurements across the surface which just wouldn't have been possible with previous technologies."