View Full Version : help me port

Chance89

07-06-2004, 02:51 PM

Can you guys help me port my box. It would have been done a while ago but its so thin I didn't wanna try. I got two 12in pioneer TS-W304f's in a box.don't exactly know what I want to tune it @ I'm thinkin 33hz

-7in top depth

-10in b depth

-60in long

-and 17in high

I don't understand the formulas...whats vb? and addl v?and there's a bunch of other stuff to :confused:

can someone teach me to use these designer's or tell me where to place and whats size the port has to be

I use ajdesigner.com

ky babyn

07-08-2004, 01:03 AM

Vb= the reqired internal volume of the enclosure

F3= the frequency that the response is down by 3 db at

Fb= the frequency that the vent needs to be tuned to

Vas= the equivelent stiffness of your driver

Fs= the free air resonance (this is your tuning frequency its a good rule two build it a few Hz higher than what your drivers requier because if you dip below your driver Fs the sound will get muddy.

to calculate your

Vb=Qts^(2.87) x 15 x Vas

Fb=Qts^(-0.9) x 0.42 x Fs

F3=Qts^(-1.4) x 0.26 x Fs

To port you are going to need these specs: Vb, F3, Fb, Vb, Qts, Vas, Fs, Xmax,

the required volume for each driver, the diameter of port you are using (inside diameter) Find these out and i will do the math. i just figured this stuff out with the use of some calculaters. what program do you use?

Trixter

07-08-2004, 11:11 AM

Becareful useing calculators. They are not all accurate. If you know the formula, use it to check the calculator....but then I guess if your going to do that you may as well not use the calculator....? Nevermind...

Just becareful which ones you use.

monte_carlo97

07-08-2004, 11:27 AM

Which calculators are good ones to use? And where can you get them at?

Trixter

07-08-2004, 09:28 PM

http://www.carstereo.com/help2/Articles.cfm?id=31

This one seems to work out well. You need to use you volume after sub and bracing displacement. After you get you length, figure out the port displacement and subtract it from your original volume. Plug this new volume into the calculator now and that will give you your correct length.

ky babyn

07-08-2004, 10:10 PM

that is the one i use however the calcs at the 12 volt are a little easier to use and you get the same answers chance how many drivers you running i cant remeber. hay trixter thank s for all your help on my porting ill be building it this weekend. cause its raining like a b!tch now for the last few days. i cheked the math and i can do most of it on paper and it is slightly more acurate. learned alot from you thanks. tty later