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Doctor Q

Port Size Problem!

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OKay so i got my car back... 15" Q in a (supposed to be) 4 cu.ft. ported box....

i love it so far and sounds great. i need to listen to it more tommorw. i hardly had any time today. but anyways, to the point...

My box is 4 cu. ft. which means the port should be 48-64 square inches.... well i have 4 3" ports which is:

1.5^2 x 3.1415 x 4 = 28.2735

if the box is 4 cu ft and i replace the 3" ported with 4" ports, that would give me about 50 (50.264) square inches but how much would it take from the rest of the box? how would it change the sound and output? and how hard would it be to change the ports out?

I think it may be restricting the sub a lil with such lil port area... idk im a noob haha

Edited by Doctor Q

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Would it be worth it to go thru the hassle and money to put in the 4" ports or should i just leave it?

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Funny thing is, port area has nothing to do with box size... At all...

This rule of thumb was made up to keep stupid people from putting 2 18" subs in a box with a single 3" port...

So in other words, you are probably fine....

If you are worried about it, run your alignment in a modeling program with your amount of power and see what the vent velocity is, if it is too high, then yes, you may need more port...

But again, relating port area to box volume is horse s*it....

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yeah, its more of a guideline to idiot proof things, but there is NEVER a set way to do a box.

if you can hear port noise (huffing/whooshing/whatever) and it bothers you enough to WANT to change the ports, do it, other than that, leave it.

going w/ bigger ports means longer ports for same tuning, decreasing box size etc.. so if you're a noob, leave it alone

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ok thanx for the help guys... so gettin bigger ports woulldnt make it any louder?

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