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Historical Speech Acoustics

June 10, 2015

How did historical leaders once address crowds of thousands, unaided by modern amplification?



Pericles oration

Pericles’ Funeral Oration (Philipp von Foltz/1852)

Re-creating historical speeches. I’m Bob Hirshon and this is Science Update.

Before the advent of modern amplification, skilled orators like Julius Caesar and Abraham Lincoln captivated audiences in the thousands with their voices alone – often outdoors. Depending on crowd noise, atmospheric conditions, and spatial acoustics, the loudest speakers in history could have been heard by crowds of 30,000 people or more, according to Princeton acoustical scientist Braxton Boren.

BRAXTON BOREN (Princeton University):

Any gathering was effectively limited by how loud their voice could be and how clearly it could be heard.


Boren says Benjamin Franklin was one of the first scientists to estimate the potential reach of the human voice, confirming reports that the loudest speakers could be heard by tens of thousands of people. Building upon Franklin’s work, Boren uses modern acoustical principles to estimate the crowd size at various historical speeches. He presented his research at the spring meeting of the Acoustical Society of America. I’m Bob Hirshon, for AAAS, the science society.

Story by Susanne Bard