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Info about sound waves?

  1. Sep 27, 2009 #1
    Hopefully i am not wasting anyones time, as i dont know alot about sound waves etc.. but i was wondering if anyone could help. Is there such a thing that recieves sound waves of around 1100hz. maybe a sound receiver and emmitter? I have tried finding as much infomation online, but there is limited results. I know this may not be the 'normal type of question' but any info would help massively.
  2. jcsd
  3. Sep 27, 2009 #2


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    Your ear, a microphone, a brick wall?
    Every object receives sound waves that reach it - not all of them do anything except absorb them.
    Do you want to detect 1100hz sound, detect only this frequency, block only this frequency or what?
  4. Sep 28, 2009 #3
    Sorry, there was no clarity in what I was asking! But yer basically Is there a device that only picks up this frequency/only picks up this frequency and above! And displays in whichever means possible(a gragh, by a light bulb, etc...) if this frequency is heard!
  5. Sep 28, 2009 #4


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    A tuning fork would respond to only one frequency (or at least a narrow band of frequencies )
    The easiest way is a microphone and either a computer and some software to pull out just that one frequency, or you can do it with an analog electronics filter.
    This is what the graphic equiliser on a hifi does.
  6. Sep 28, 2009 #5


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    Many hand held acoustic analyzers will do what you are looking for as well. They will pick up all frequencies up to a certain limit and will have customizable displays that you can tailor to whatever you are looking for.
  7. Sep 28, 2009 #6
    Hello Callumbrad-
    Here in thumbnail is a simple 1-opamp tuned narrowband amplifier that can be used with a microphone [STRIKE]or loudspeaker[/STRIKE] input. Voltage source V2 in circuit is a 1-millivolt signal that is swept from 500 Hz to 2000 Hz. The output signal is maximim at 1100 Hz, with an amplitude of 200 millivolts.
    [added] It is straight forward to ad an op-amp that lights a LED if the sound signal level exceeds a threshold at the output of this circuit.
    [added2] The LT1014 is equivalent to the LM324.
    Bob S

    Attached Files:

    Last edited: Sep 28, 2009
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