View Full Version : port

07-06-2006, 11:54 PM
ok.. so i have used two different calculators.. and they give me different port tuning answers...

the one built into bassbox pro 6 gives me one thing... and the calculator on carstereo.com, the port area then port length calculators, give me different ones. which one should i go with?

07-07-2006, 04:02 PM
pencil and paper, my friend, leaves no questions.

Lv = (14630000 x R^2) / (Fb^2 x Vb) - 1.463 x R

Lv = length of vent
Fb = freq. of box
Vb = volume of box (in cu inches)
R = radius of port

(if using a slot or square port, then R = sq.rt. (port area / 3.14)

when doing this formula you need to do it twice. first do it to get the port length. now figure the port's displacement including all materials of construction. subtract this number from the original Vb and re-calculate.