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    PSturmer's Avatar
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    different length ports in one box

    i was wondering if you had 2 4'' aeros of different lengths in the same box how this affects spl and how to calculate tuning frequency.

    thanks



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    Re: different length ports in one box

    why in the hell would you want to do that?



    Quote Originally Posted by captaincheesey View Post
    I don't know because I am blindfolded and tied to the bed. I think I hear the clothes washer in the background sometimes, so maybe she is looking at laundry? Idk

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    Re: different length ports in one box

    Quote Originally Posted by PSturmer View Post
    i was wondering if you had 2 4'' aeros of different lengths in the same box how this affects spl and how to calculate tuning frequency.

    thanks
    it probably wouldnt help. but why not just try it?

    i wouldnt, but if you got the time why the **** not. just make sure and say you were baked as hell when you thought/did this so you have a cop out when **** hits the fan



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    Re: different length ports in one box

    i dont have access to a band saw untill monday so i have to use the ports i have already.



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    Re: different length ports in one box

    Quote Originally Posted by PSturmer View Post
    i dont have access to a band saw untill monday so i have to use the ports i have already.
    then wait until monday

    you can also use a hack saw or a chop saw if need be



    Quote Originally Posted by captaincheesey View Post
    I don't know because I am blindfolded and tied to the bed. I think I hear the clothes washer in the background sometimes, so maybe she is looking at laundry? Idk

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    Re: different length ports in one box

    In theory the shorter port would have a smaller air mass than the longer port, therebye offering less resistance and being tuned higher. This shorter port would be unloading at the lower frequencies that the longer port would be tuned for, rendering the long port's tuning range useless. If the longer port was substantially longer, it might have enough air mass that it would not effect the shorter ports tuning range, acting as if the longer port were alltogether not present, so the short port could do its job at the higher tunning. But this is unlikely the case, and pointless if executed.

    In the case that the length of the two ports is very similar, the overall tuning of the system will take on the characteristics of the shorter port, but when playing frequencies below the shorter ports tuning range, the short port will unload first and more easily than the long one, and therefore generate more port noise, wind, ect than the longer one would.

    The only time port lengths should differ is when port diameter differ also e.g. mixing a 3" and 4" diameter port.



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    Re: different length ports in one box

    Quote Originally Posted by bigbang View Post
    In theory the shorter port would have a smaller air mass than the longer port, therebye offering less resistance and being tuned higher. This shorter port would be unloading at the lower frequencies that the longer port would be tuned for, rendering the long port's tuning range useless. If the longer port was substantially longer, it might have enough air mass that it would not effect the shorter ports tuning range, acting as if the longer port were alltogether not present, so the short port could do its job at the higher tunning. But this is unlikely the case, and pointless if executed.

    In the case that the length of the two ports is very similar, the overall tuning of the system will take on the characteristics of the shorter port, but when playing frequencies below the shorter ports tuning range, the short port will unload first and more easily than the long one, and therefore generate more port noise, wind, ect than the longer one would.

    The only time port lengths should differ is when port diameter differ also e.g. mixing a 3" and 4" diameter port.



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