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Reload Thread: Yet another Port Q

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    Yet another Port Q

    This box is 2cuft and needs a 4" Port at 15 3/4" in length.




    The flat face to the right is where the Sub will be placed and the sloped end sits against the rear seat of a 4runner.

    Port question; the port can be placed on the baffle, but would require a bend to get the 15 3/4"............

    Or I can just place the port on the side face and run a straight shot.

    Would one be more accurate than the other, or would the difference be too miniscule to worry about?


    Thanks in advance.







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    Re: Yet another Port Q

    if there is at least 4" of space between where the port opens up and the side othe car you're ok.

    also, a single 4" port isn't enough port area. you should go with two that are each ~35" long, hope you can make it work!

    box looks great, BTW. i like the slanted back!




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    Re: Yet another Port Q

    Quote Originally Posted by xluben View Post
    also, a single 4" port isn't enough port area. you should go with two that are each ~35" long, hope you can make it work!
    Dude, tell me if I did, or am going to do wrong

    I got the measurements from www.bcae1.com






    Thanks for the Compliment though




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    Re: Yet another Port Q

    you're doing a round port right?

    usually two 4" ports are recommended per sub or ~25in^2 of port area.

    it probably would have been a lot easier to do a slot port

    to get that tuning frequency with two 4" ports they're going to be very long.

    you could try your original design, but i fear you'll get port noise




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    Re: Yet another Port Q

    Quote Originally Posted by xluben View Post
    you're doing a round port right?

    usually two 4" ports are recommended per sub or ~25in^2 of port area.

    it probably would have been a lot easier to do a slot port

    to get that tuning frequency with two 4" ports they're going to be very long.

    you could try your original design, but i fear you'll get port noise
    I reckon I'll have to find out

    I went with the round port to try and save room in the rear. I've have two slot ports made already, just trying others.




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    Re: Yet another Port Q

    This for an Infinity 12 right? My buddy has one in a 1.7 cubes box with a 4 inch port, and its fine. No noticeable port noise. More port area is better though. I usually go with about 1/3 SD for port area in normal installs.




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    Re: Yet another Port Q

    i say this sooo often. port calculators do not account for port displacement. if you made the box knowing the port displacement ahead of time and included it in your design, your fine. if not you will need to do the math twice. once to get the port length and find it's volume. and again using the box volume with the port volume subtracted from it. make your port to the second calculation's length.



    2006 Jeep Liberty
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    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: Yet another Port Q

    Quote Originally Posted by Trixter View Post
    i say this sooo often. port calculators do not account for port displacement. if you made the box knowing the port displacement ahead of time and included it in your design, your fine. if not you will need to do the math twice. once to get the port length and find it's volume. and again using the box volume with the port volume subtracted from it. make your port to the second calculation's length.
    that one does. he's fine with the single 4" dia port.




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    Re: Yet another Port Q

    Yaay

    We'll see if the difference is noticable between a slot vent and the single 4"




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    Re: Yet another Port Q

    Quote Originally Posted by xluben View Post
    that one does. he's fine with the single 4" dia port.
    i guess it can...i get 15.1" long...close enough. i don't see an option for choosing that though....or is it in writing and i just missed it. it would be nice to have an option.



    2006 Jeep Liberty
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    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: Yet another Port Q

    i get 15.1" long...close enough. i don't see an option for choosing that though....
    Quote Originally Posted by acreature View Post

    That's what it stated ^

    I said 15-3/4" b/c at the time of the initial post, I was going by memory




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    Re: Yet another Port Q

    Gotta get some caulk, then it'll be about ready to test.



    Got a peice of MDF cut to go around the woofer, and going to do something with the blank side to the left of the woofer, just not sure what til I test and make sure it's a keeper.




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