Voice coil inductance

Discussion in 'Archived Threads 2001-2004' started by Stephen Dodds, Sep 22, 2002.

  1. Stephen Dodds

    Stephen Dodds Second Unit

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    I'm modelling various woofers for a (stereo) bass cabinet that will be crossed over at about 150hz. Using Unibox, there seems to be considerable roll-off with one otherwise good looking driver (SEAS L21RN4X/P) with an Le of 2.7mH.

    How important is this in real life? Do I attempt to flatten out the response or just treat it as normal roll off. There is another driver the seems almost as good that has lower inductance (SEAS L21RNX/P)and thus lesser roll off. Would this make it a better choice perhaps?

    Thanks to all for helping me learn.

    Steve
     
  2. Isaac C

    Isaac C Stunt Coordinator

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    At that crossover frequency, the upper natural roll-off of the woofer shouldn't matter as it happens higher up around 700Hz (see datasheet) or so anyway.
    Note that Unibox, winISD, SubSim and other similar programs should only be used up to 200Hz - 300Hz. Beyond that the calculated acoustic response is no longer valid, that's just the nature of the internal mathematical models. But the calculated electrical response beyond 300Hz or so is still better than a flat, zero inductance, impedance.
    [​IMG]
    Isaac
     
  3. Stephen Dodds

    Stephen Dodds Second Unit

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    Thanks Isaac. Is there then a negative to high Le apart from roll off considerations?


    Steve
     
  4. Isaac C

    Isaac C Stunt Coordinator

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    No problem [​IMG]
    None that I could think of (it's past 2am already).
    [​IMG]
    Isaac
     

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