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Sound level meter

  1. Nov 10, 2009 #1

    what ICs can u suggest to be used in my sound level meter for outdoor speakers in order to have an accurate measurements. power amplifier to be used will be 50, 70, 100 watts power out put.
  2. jcsd
  3. Nov 10, 2009 #2


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    Analog make a wonderful logarithmic amplifier chip, the AD8307 which would be great.

    But, seriously, go and buy a sound level meter. They are cheap and come already calibrated and in a nice case with a guarantee.

    This is an example:
    You can get better ones, too, but this one looks fine for general use.
  4. Nov 10, 2009 #3


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    Even if you build you still still have to calibrate it, which can only be done using another sound level meter....

    Calibrating sound level meters is actually quite tricky. Even commercial ones are often quite limited and only really useful for "noise", they are often very inaccurate at e.g. low frequencies (the one I have at home is useless below about 100 Hz).
  5. Dec 4, 2009 #4
    im going to use LM3916 IC for my sound level indicator. i want to canvass how much would be the cost of one IC LM3916 and if i will order a large quantity,how much will be the shipping cost.
  6. Dec 4, 2009 #5
    my thesis proposal will be a sound level indicator for loudspeaker using LEDs. this will be a bar graph display that will indicate the level of the sound of a certain loudspeaker.what ideas can u share about my thesis proposal?
  7. Dec 4, 2009 #6


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    You could try this:
    http://www.findchips.com/avail [Broken]

    This is from the
    Sticky: Useful EE Links and Search Engines

    Those chips are readily available for less than $2. Shipping would be much the same whether you order one or 20, so it is worth getting a big batch in one go if you need them.
    Last edited by a moderator: May 4, 2017
  8. Dec 5, 2009 #7
    Like these? http://www.discovercircuits.com/V/vu-meter.htm
  9. Dec 7, 2009 #8
    i want to ask some ideas about the significance of my thesis.. because it takes me a lot of time thinking,wat wud be the importance or the objective of my thesis proposal.. pls help me realize the significance of my thesis...
  10. Dec 7, 2009 #9


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    You would need to talk to your teacher about this.

    Just building someone else's circuit off Internet probably would not be enough at thesis level.

    You would need to consider the frequency response of microphones and check up on different types of weighting for the frequency response.

    A 3916 will give poor output resolution as it gives stepped output.

    You will probably need extra gain too, as the output of a microphone is quite low.

    Do you have another sound level meter to calibrate yours off?
  11. Dec 8, 2009 #10
    i don't have a sound level meter. but i want to purchase... how much is a typical sound level meter....and its shipping cost?
  12. Dec 8, 2009 #11
    can u suggest a circuit design for a sound level meter?
    and its testing strategy....plzzzzz.
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