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Bell ringing frequency

  1. Dec 2, 2008 #1
    How do I calculate the frequency of an 8.5 cm diameter bell ?
    The bell is cast brass for resonance, but I intend to activate it with a buzzer so sound will last for more than a few seconds. Does the weight affect anything other than volume ? I intend to use it inverted, supported near the "top".
  2. jcsd
  3. Dec 3, 2008 #2


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    You don't.
    For a real bell you would need to use numericial methods to solve the equations (unless you have a VERY simple bell, i.e. something very symmetric) but even then you are not very likely to get a useful answer, partly because real bells are note made of a "perfect" material; various imperfections etc (which in turn depends on how the bell was cast) can have quite a large influence on the resonance frequency.

    Is there any reason why you simply can't measure the frequency? It should be easy, all you need is a microphone connected to the sound card of a computer+some suitable software.
  4. Dec 3, 2008 #3


    Staff: Mentor

    Here is a description of what you have to do to http://www.rps.psu.edu/sep99/freedom.html".

    "dividing the surface of the bell into a grid made of 450 squares. 'There's an equation describing the vibration of each square, and the computer can solve all the equations simultaneously,' "
    Last edited by a moderator: Apr 24, 2017
  5. Dec 3, 2008 #4
    "a traditional English-bell profile "
    What I need is the "dominant strike chord"

    Any suggestions on "some suitable software" ?
  6. Dec 3, 2008 #5


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    Well, all you need is some software that can show you the frequency spectrum of the signal from the microphone. Sigview comes to mind and you can download a free trial version.

    However, you could also try something VERY simple such as AP Tuner which is a program used to tune guitars, by default it will only show you what note you are playing (i.e. A, C# etc) but if you look n the "Recording Device and Calibration" it will also show you the last detected frequency.
    Or, alternatively, you could just look up what frequency e.g. C# corresponds to (chances are that a bell will be reasonably well "tuned" to a note).
  7. Dec 4, 2008 #6


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  8. Dec 18, 2008 #7
    I need piezo(?) alarms to ring my bell. I need a resonant frequencies of 392 hz and 1700 hz, 12 volts would be best. Also need a 30 minute timer.
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