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Equations of moton for a bass reflex loudspeaker

  1. Jan 16, 2005 #1
    I am trting to derive the equations of moton for a bass reflex loudspeaker with two degree of freedom. any one out there ever done this??
  2. jcsd
  3. Jan 16, 2005 #2


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    This could be very involved since the system is modeled as an eletrical fourth order filter. The speaker cone motion should (according to theory) show no movement near the enclosure resonance but varies because of non-linearities. The air within the port also has many non-linear aspects.

    The work of Thiele and Small offered many insights into the very small signal level behavior, but at higher drive levels the complexities generally leave the modeling to devoted programs like LEAP that can accurately account for the non-linearities.

    http://linearx.com/products/software/LEAP5/LEAP5_01.htm [Broken]

    Is this for a school project? Or for an application like sound reproduction. For the former, the AES papers by Thiele & Small from the late 60s (along with many others) offer tons of insight. For producing a loudspeaker, there are far cheaper and reasonably accurate software and the Loudspeaker Design Cookbook by Vance Dickason offers a simplified layman's approach to all aspects of loudspeaker system construction.

    Last edited by a moderator: May 1, 2017
  4. Jan 17, 2005 #3


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    I would suggest looking at Art Ludwig's web site: http://www.silcom.com/~aludwig/index.htm

    Art has a very extensive site on the physics of sound in regards to sound systems. He has some great information. He has a section devoted to system design that may answer your question:

    If anyone is ever interested in building a custom entertainment room or anything related, I HIGHLY recommend Art's web site!
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