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    Icon12 Can't figure out port tuning

    I have a box 33 wide by 13 high by 11 deep. The port is 4 inch x 15. Can someone please assist me in figuring out what this port is tuned to? I appreciate any responses.







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    Re: Can't figure out port tuning

    I assume it is a 4" round port at a length of 15".

    I'm getting approx. 34hz. Someone correct me if I'm wrong.



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    Re: Can't figure out port tuning

    Yep 4 inch round. Ok I kept getting calculations between 30 - 32, but the main issue was some places were saynig that a shorter port like 8.9" would give me the 30 hz tuning.. that threw me for a loop.




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    Re: Can't figure out port tuning

    Anyone else?




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    Re: Can't figure out port tuning

    If you guys are using WinISD to check, how do you take the effects of the different speakers out of the equation? I'm not sure how to start a project without having to choose a speaker first, and once I've chosen a speaker it effects the way the numbers are calculated.



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    Re: Can't figure out port tuning

    no...it effects the graphs...not the numbers



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    Re: Can't figure out port tuning

    32 HZ before sub displacement.....1.956 cubes @ 31.96 hz



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    Re: Can't figure out port tuning

    Quote Originally Posted by iamamp3pimp View Post
    no...it effects the graphs...not the numbers

    32 HZ before sub displacement.....1.956 cubes @ 31.96 hz
    So did you find the volume of the box and subtracted the volume of the port to get 1.956? Doesn't the program account for the displacement of the sub also?



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    Re: Can't figure out port tuning

    yes thats how i got it...the volume of the port and 1/4 inch to account fopr the PVC displacement.


    thats assuming its 1/8th thinwall.



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    Re: Can't figure out port tuning

    If assume .08 cu/ft displament for the driver and that it is a 4.20 OD port I get net box volume = 1.89 cu/ft @ 22.40Hz




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    Re: Can't figure out port tuning

    The driver is a DLS SP12, magnet is pretty large. http://www.dlsamerica.com/pdf/manrultsub3.pdf thats the manual for it.

    So i could potentially be tuned as low as 22.4 hz?! God this is confusing. So With the way its tuned, if I was running a 30hz ssf would that be a bad thing?




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    Re: Can't figure out port tuning

    It's no where near 22hz. I have a net volume of 1.8 cubic feet after port, sub, and wood thickness. The tuning I came to was 32hz.



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    Re: Can't figure out port tuning

    Thats what I get! Maybe he meant 32.4.




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    Re: Can't figure out port tuning

    edit... actually, u guys helped me with my math.. I had the wrong number pluged into my equations.

    yes = 32.4with 1.8cu/ft net
    Last edited by rpfuror; 12-15-2006 at 09:31 PM.




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