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    INCLUDE port volume in boxes????

    I asked a Parts Express tech guy on how to find the volume of precision (aero) ports, since they have flared ends, to count for thier displacement. This is what his reply was:

    Actually, there are two schools of though on this. The first and most
    recent says that the volume of the air in the tube should not be
    considered as lost. Vance Dickason has always said in the
    cookbook that the volume should be added.


    So does this mean you don't have to worry about port displacement?? He also went on to say:

    As you probably already know, the standard formula for the area of
    a cylinder is pi times the radius squared times the length in inches,
    divided by 1728. This of course gives cubic feet which you would
    add to your target cabinet volume. I don't believe that the internal
    flare could add any significant amount, and I'm aware of no
    applicable formula. I can't imagine it having an affect, audible or
    otherwise.


    I'm thinking of just trying to figure it out myself. It probably won't be exact, but it would be be darn close.



    2006 Jeep Liberty
    Adire Audio, Cadence, Clarion, MB Quart

    Lv = [(14630000 x R^2) / (Fb^2 x Vb)] - 1.463R
    *Vb = vol. in cu"
    **R = sq.rt. A / Pi (for square/slot port)




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    Re: INCLUDE port volume in boxes????

    port displacement takes away from box volume




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    Re: INCLUDE port volume in boxes????

    That's what I always thought, but this guy says not to count it as a loss and that it should be added...wtf.



    2006 Jeep Liberty
    Adire Audio, Cadence, Clarion, MB Quart

    Lv = [(14630000 x R^2) / (Fb^2 x Vb)] - 1.463R
    *Vb = vol. in cu"
    **R = sq.rt. A / Pi (for square/slot port)

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