Inductor value, help!

Discussion in 'Portable Disc & Media Players & Recorders' started by plynchy, Jun 6, 2005.

  1. plynchy

    plynchy
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    Hi all,noob here. After some advice re an inductor value on the component set in my car. The set consists of,in order from the amp output:
    8" Sub, 4" mid, 2" tweeter,max 100w rms(per channel) fed from a 2 channel 150w amp.
    The problem i have is that the inductor on one of the subs is fooked(destroyed,don't ask),i understand that these are in place as the "crossover" to isolate the low end freq. from the mid + tweet.
    I still have 1 good one but ideally would like to replace them both.
    Can some clever person tell me how to find out it's value and where to obtain a replacement please,have tried Maplins and RS but need to determine it's value first!
    Thanks in advance... :thumbsup:
     
  2. ched

    ched
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    hi, I can offer some advice, the crossover for a 3 way speaker system will actually be designed for those exact drive units. So in theory you need to know the value of the inductor and the type of filter ( Butterwick, Bessel etc).
    For example a 4.2mH would give a 150Hz low pass 1st order filter.
    I would say that if you would require an Inductor of about 0.2mH for a 3.5Khz low pass filter.
    This is a link to a page with some crossover component calculators which may help? http://www.apicsllc.com/apics/Misc/filter2.html

    So at a very vague guess you need an inductor about 0.2 mHenrys that can take the power. Unfortunately I dont know where to buy them, but if and when I find out I will post the url.

    Sorry I cant be of more help.
     
  3. ched

    ched
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  4. paul_mcneil

    paul_mcneil
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    Maybe wise to find out whats caused it before simply replacing!!
     
  5. micb3rd

    micb3rd
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    Do you not have a low pass filer on the amplifier or headunit?

    Or if not check ebay for a cheap active crossover, it will be better than a passive and you can tune it better.

    Or....

    http://www.dls.se/pdf/soundhandbook05.pdf

    I have made a few first order 6db passives from this before, it is a good read!
     

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