View Full Version : round port calculation

pwnt by pat
11-24-2006, 11:55 AM
I'm trying to find port length for a round port. Using the calculations for diysubwoofers.org, for a 1" port, I get a 2.882088858" port lenght, however, using winisd alpha, I get a 4.53" port length. Is the winisd calculation for port length wrong or am I?

11-24-2006, 12:00 PM
Seeing how we don't know the net volume of the enclosure, there is no way we can tell you what is correct.

What application would you be using a single 1" diameter port?

pwnt by pat
11-24-2006, 12:08 PM
Oh my bad. I knew to include that, but slipped my mind.

0.250 net @ 40

It's for a 6.5" midbass in door pods, and I'm considering porting 'em, but am trying to find length to determine if the depth will be too great.

looks like I missed a decemial point in my excel spread sheet (work in progress... heh). min diameter looks to be 4.25"

It's for the 6.5" Adire SF7 driver, specs here:
Fs: 48 Hz
Qms: 6.2
Qes: 0.72
Qts: 0.66
Vas: 14 liters
Sd: 140 cm^2
Xmax: 8mm one way linear, 12mm one way peak
Re: 3.5 Ohms
Le: 0.45 mH

pwnt by pat
11-24-2006, 01:29 PM
nevermind, I see where I was ****ing up.

37" port length for 40hz tuning on .3 cu ft... not going to happen