3B55.30 - Speaker and Baffle

Code Number:
Demo Title:
Speaker and Baffle
Speaker Construction, Constructive & Destructive Interference
Area of Study:
Plexiglas plate with hole, Homemade Paper Speaker in Plexiglas Frame, Magnet, Tape Deck, and Amplifier.

Plug the homemade speaker into the amplifier and start it 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.

  • 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.

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