Set up for Speaker and Baffle demo

 

Code Number: 3B55.30

Demo Title: Speaker and Baffle

Condition: Fair

Principle: Speaker Construction, Constructive & Destructive Interference

Area of Study: Oscillations & Acoustics

Equipment: 

Plexiglas plate with hole, Homemade Paper Speaker in Plexiglas Frame, Magnet, Tape Deck, and Amplifier.

Procedure:

Plug the homemade speaker into the amplifier and start the tape player playing.  The difference in sound quality with and without the Plexiglas plate should be apparent.  The amplifier will have to be turned up quite far for the homemade speaker. This speaker will also move back and forth on the magnet, at times rather violently.

References:

  • Peter Heller,  "Drinking-Cup Loudspeaker - A Surprise Demo",  TPT, Vol. 35, # 6, p. 334, Sept. 1997.
  • Chris Chiaverina, "Softspeakers", TPT, Vol. 24, # 1, Jan. 1986, p. 55.
  • W- 335:  "Cheap Speaker Cabinet",  DICK and RAE, Physics Demo Notebook.
  • Robert Ehrlich, "11.1 - Speaker in a Board", Why Toast Lands Jelly-Side Down, p. 171.
  • "Interference of Sound Waves",  PIRA Newsletter.  Vol. 3, No. 17, Jan. 1990.
  • Ron Hipschman, "Ear Piece", Exploratorium Cookbook II, p. 113.1 - 113.2.
University of Maryland Physics Department QOTW Question #165
University of Maryland Physics Department QOTW Answer #165
3B55.30 - Speaker and Baffle
3B55.30 - University of Maryland QOTW Question #165
3B55.30 - University of Maryland QOTW Answer #165