Resonance Boxes

Identifier: M: WM&S - 021

Two resonance boxes and a mallet

Concept Overview

  1. Resonance
  2. Beats

Lecturer Procedure

Steps to FollowExpected Result
  1. Use the mallet to strike the bar of 1 resonance box.
  2. After tone is heard clearly, place hand on top of the bar to stop the vibration.
The other resonance box will continue to produce sound.
  1. With the clip on 1 of the resonance boxes, strike each box.
Beats can clearly be heard.

Historical References; Taken from original work of Percy H. Carr, 1970 

“For reasons I do not understand, this experiment works much better when a certain one of the bars is the exciting bar. By experiment before class find out which one it is.”
 

“I have never approved of [using the detuning clips as part of] the demonstration as it is obvious that scratching of the bar results, and it must slowly deteriorate as a true resonating bar. The clip was not furnished by the makers. It appeared; from where I know not. The bar is somewhat corroded by finger oil.”

Video Demonstration

Transcript:

There are no spoken words with this recording.