3E20.10 - Loudspeakers

Code Number:
3E20.10
Demo Title:
Loudspeakers
Condition:
Fair
Principle:
Speaker Construction and Sound Reproduction
Area of Study:
Acoustics
Equipment:
Loudspeakers, coil and cones, magnets assemblies.
Procedure:

Show and tell the major parts and components of loudspeakers.

This speaker can be used to show large oscillations of the speaker cone.  Use 5 to 10 Hz. on the function generator.  The 600 watt amplifier will have to be turned all the way up to see to so oscillations that are visible in the large classrooms.  The speaker is rated to take this amount of wattage.  The best oscillations occur around 8 Hz.

References:
  • Kasey Wagoner and Daniel Flanagan, "Speaking of E&M", TPT, Vol. 57, #2, Feb. 2019, p. 78.
  • William Reitz, "Two Sound Ideas", TPT, Vol. 55, #6, Sept. 2017, p. 378.
  • Rhett Herman, "As Simple as Possible", TPT, Vol. 40, # 2, Feb. 2002, p. 182.
  • Molly Johnson,  "Sound Science - A Simple and Robust Hands-on Loudspeaker Activity",  TPT, Vol. 37, # 6, p. 350, Sept. 1999.
  • Peter Heller,  "Drinking-Cup Loudspeaker - A Surprise Demo",  TPT, Vol. 35, # 6, p. 334, Sept. 1997.
  • Allen Keeney and Brant Hershey, "Making Your Own Dynamic Loudspeaker", TPT, Vol. 35, # 5, p. 297- 299, May 1997.
  • Chris Chiaverina, "Softspeakers", TPT, Vol. 24, # 1, Jan. 1986, p. 55.
  • W- 425:  "Bite-a-Phone", DICK and RAE, Physics Demo Notebook.
  • "Nanotube Loudspeakers", Physics Today, Vol. 62, #1, Jan 2009, p. 17.
  • Rob Sabin, "Build Your Own Speakers", Popular Mechanics, Aug 2008, p. 115.
  • Rafi Letzter, "Learn to Make Speakers from Post-Its", Popular Science, Feb. 2015, p. 67.
  • Corinne Iozzio, "Speakers From Space", Popular Science, Jan. 2013, p. 14.
  • Mark Davids, et al., "The Photophone", Teaching about Lightwave Communications, 1994, p. 3-7.
  • Allen Keeney and Brant Hershey, "Making Your Own Dynamic Loudspeaker", Apparatus for Teaching Physics, p. 126, Edited by Karl Mamola.
  • H. Richard Crane, "Never Throw a 2-Inch Speaker Away: It Has Many Uses", How Thing Work (1983 - 1995), p. 120.
  • H. F. Olson, "Modern Sound Reproduction", Chapter 2, Loudspeakers, p. 19.
  • Cy Tymoney, "Sneaky Intercom", Sneakiest Uses for Everyday Things, p. 39.
  • William Gurstelle, "Crispy, Crunchy Audio", Popular Science, March 2013, p. 71.
  • Curt Suplee, "Resistance: Pros and Cons", Everyday Science Explained, National Geographic, p. 96.
  • Grant Mellor, "The Juice-Can Speaker", Flying Tinsel, 1993, p. 110.
  • "Loudspeaker",  The New Illustrated Science of Invention Encyclopedia: "How it Works",  p. 1482.


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