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    southstylestang's Avatar
    southstylestang is offline crazy white boy



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    need help figuring port demensions

    Im gonna be building a box for my Fi 12 BTL b/c my last one didnt fit. It wasnt tall enough and i wasnt thinking about the front being angled too much for the magnet to fit. Plus it was a smaller box. So I designed a new box. im going to put the sub facing the front with triple baffles. I just need help designing the port for this one. Not sure wether to use a round port or a slot port. I wanna tune it to 32 hz. Could somebody help me figure the deminsions for a port. The box according to rockfordfosgates boxwizard the box is going to be 3.3 cu ft before the port and sub displacement. Heres a pic RF calculator i used to figure the area.



    And heres a pic of the design from sketchup. I have the sketchup pic saved too if somebody wants to use it to design the port.



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    germanyt's Avatar
    germanyt is offline CarAudio.com Elite



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    Re: need help figuring port demensions

    http://www.carstereo.com/help2/Articles.cfm?id=31
    i like this calculator. just do a litle math and it will tell you how long it needs to be. the length is assuming net volume so take that into consideration



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    Trixter's Avatar
    Trixter is offline Keepin it Simple



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    Re: need help figuring port demensions

    Quote Originally Posted by germanyt View Post
    http://www.carstereo.com/help2/Articles.cfm?id=31
    i like this calculator. just do a litle math and it will tell you how long it needs to be. the length is assuming net volume so take that into consideration
    yeah...you need to use the calculator once to find the length and then figure out the displacement. subtract the displacement from your original volume and plug the numbers in again to get the length you cut to.



    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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    southstylestang's Avatar
    southstylestang is offline crazy white boy

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    Re: need help figuring port demensions

    ok so if i done my math right (which i prob didnt) then i could use 4 2inch pvc pipe with a length of 9.25 each for a tuning of 32hz. box would be 3.3 b3 and 3 cu ft after port and sub displacement. does that sound right?



    FOR SALE
    1991 3000GT SL
    Memphis 6.5's front and back - profile 4 ch
    Diamond Audio D312D4
    3 Diamond Audio 15's, box, Cadence Ultrashock amp.
    Fi BTL 12in fully loaded - cooling
    Cadence Ultradrive z1500
    Mmats procast 15

    REFS: sold to-
    Xavierracing (RF 500.2), blaze383 (2 diamond audio 12s), wonger (cd player)
    traded with-
    DaGh0st(xbox 360 for btl 12), vette1(diamond audio 12 for sub box)
    bought from-
    jonnybusa, ccajun4real(x2), rob_z89, j3bus2k3, urlost, trevor87

  5. #5
    Trixter's Avatar
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    Re: need help figuring port demensions

    thats only like 12.5sq" of port you will need a least 36sq"...(i do a minimum of 12sq" per cu'....a lot of guys will tell you to do more but for a single 12 30-36 should be fine.)



    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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