DorianBryant

Port length help

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.

DorianBryant

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?

Patrick Sun

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.

"I am a leaf on the wind, watch how I soar!"
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DorianBryant

Thanks Patrick.

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