Hear the Sound of the Liberty Bell

Independence National Historical Park 

Black and white photo of an X-ray of the Liberty Bell, showing the clapper and brace inside.
Modern technology allows us to

NPS photo

What did the Liberty Bell sound like to Benjamin Franklin?

In 1999, graduate students from Penn State University were able to digitally create a structural model of the Liberty Bell.  From this computer model, they were able to mathematically equate the vibration of the bell and add sound. Knowing that the original tone of the bell was E-flat, they were able to come up with an approximation of the original sound of the Liberty Bell.

Does the bell still ring today?

The Liberty Bell cracked beyond repair on February 23, 1846. While the bell does not ring physically, its message of liberty still rings out to many.

The Liberty Bell's clapper has been immobilized since 1915. Even though the bell can't ring with the clapper, it has been struck with a mallet and the sound recorded. Listen to the June 6, 1944 nationwide broadcast of the Liberty Bell and you'll hear what that sounds like.  That day, Mayor Bernard Samuel struck the Liberty Bell seven times, one time for each of the letters in the word "Liberty" to announce the allied invasion of Europe on the beaches of Normandy, France (broadcast courtesy WIP CBS Radio).  To preserve the Liberty Bell, we no longer strike it with a mallet or anything else.

Play the "Ring the Liberty Bell" activity on the park's FREE mobile app and "ring" the Liberty Bell yourself!