Port length help

Discussion in 'Home Theater Projects' started by DorianBryant, Dec 30, 2004.

  1. DorianBryant

    DorianBryant Screenwriter

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    I just received a 3" precision port. When you calculate the port length on the calculator on their website, is this referring to the center length or the entire port length including the flares. I get 11.92 for the length,but am not sure if this is the length of the center tube.

    This is for an 85L shiva.
     
  2. DorianBryant

    DorianBryant Screenwriter

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    By following their directions, it looks like the entire port length would be 12.92 inches to get down to 22 hz. Is this reasonable?
     
  3. Patrick Sun

    Patrick Sun Moderator
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    Rule of thumb for flared ports:

    To find the equivalent straight port length for a flared port, simply subtract 1 inch from the total end-to-end length.

    So if the flared port measures 11" from end-to-end with the flared pieces in place, it is equivalent to a 10" long straight port. Cut down or add to the center portion to arrive at the necessary port length (calculated for using a straight port).

    There is some possibility that a single 3" port will contribute some port noise/chuffing sounds if the subwoofer is pushed to produce high volume of bass.
     
  4. DorianBryant

    DorianBryant Screenwriter

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    Thanks Patrick.

    Also, what seems to be the "ideal" tuning freq. for the 85l shiva?
     

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