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View Full Version : Port Area Question



Acidburn
04-25-2004, 05:38 PM
ok, i know for pure SPL you want as much port area as possible but does having large amounts of port area decrease SQ? even if its tuned low-ish like 34hz

454Casull
04-26-2004, 09:51 PM
No, as a matter of fact, the greater the cross-sectional area of the port, the less chuffing there is at higher excursions, so you get more music and less noise.

EDIT: And I wouldn't say 34Hz is a "low" tuning point, either. It isn't too high, but something like 20-25Hz is low.

kingpin_jeffie
04-27-2004, 12:22 AM
34 is pretty low I mean I dont know too many people who have the woofer in their car tuned below 30Hz.

Acidburn
04-27-2004, 01:06 AM
i didn't mean that 34 was low, it was just a number to put up, but so basically if you can get 400 square inches of port, it'd be good?

kingpin_jeffie
04-27-2004, 01:11 AM
Yea itd be good but nearly impossible to do.

Acidburn
04-27-2004, 01:12 AM
why? ...10char

Acidburn
04-30-2004, 12:11 AM
bump......

Benny212
04-30-2004, 12:29 AM
larger port area means you need a longer port
for example in a box thats 4 cubes after displacement tuned to 34 hz with a 10"x10" port it needs to be 49.82" long (winisd)
in that same box with a port thats 40"x10" the port needs to be 210.25" long
so 400 sq inches of port area is pretty impractical, but I suppose you could do it if you wanted to

Acidburn
04-30-2004, 12:36 AM
this isn't going in a Civic or anything, just theory... so it is possible? just need a hugely long port?

RMKrider1
04-30-2004, 01:39 AM
I've heard you actually start going downhill after the port area gets larger then the cone area, So 400 sq. inches would be a waste

Acidburn
04-30-2004, 01:42 AM
I've heard you actually start going downhill after the port area gets larger then the cone area, So 400 sq. inches would be a waste
alrighty, that's what i wanted to know

so the port area shouldn't be larger than the cone area of all sub(s) combined?

RMKrider1
04-30-2004, 01:46 AM
I think thats right.......BUT I have no proof to back this up!! I've only heard this mentioned a few times.
Maybe rangerman or bigbassman will read this and help out

Acidburn
04-30-2004, 01:47 AM
thanks for your help, i hope one of those guys could give me a definite answer

B_Master_Flash
04-30-2004, 01:56 AM
Im pretty sure I've heard Lloyd say that for spl comp. you want to have the port area to equal Sd

Acidburn
04-30-2004, 02:01 AM
Sd is cone area? and Sd of all subs combined?