Port Design, box for 18"Q 6.7cu. ft.. Aero port...

[snb778 1]

Hey guys

Im going to build a new box for my 18" Q.

I have 6.7cu. ft. before disp. and port.. which I know is small, which is why I need to use aero's.

Right now I have 4x 4"x10" aero ports.

can someone give me recommendations. Do I need to get 6" ports?? I know for port area that 2 of these 4" aero's isnt enough, but I think if I go to 3, mine are to short... Can I use the flares, and use PVC pipe to make them longer??

[snb778 1]

anyone.... I could use some help here... people say don't use PVC because it isnt flared right??

[snb778 1]

17 views and no help...??

[///M5 2,833]

Yours are too short. As for making them longer, it will really depend on which ones you have and either way your box will end up too small. You should buy a 15" instead of an 18" driver.

[snb778 1]

well after port and disp. I figured i'd be at about 6.4-6.5 cu. ft. a 15" wouldn't give me the output im looking for. Thats why I want to go ported with what I have.. not quite there yet for my preferences... actually it can get there, but its pretty much maxed out at that point.

I am going to go with 3x 4" aero's, w/ PVC in the middle... I just don't know how much port to use????

[snb778 1]

any of you 4 watchin... please drop in some advice if you are informed on the subject

[aznboi3644 2]

make your own flares with a router

I would use two 6 inch pvc ports

[dbjunior 0]

i have a q18 and have tried a few setups. my advice follow fi's suggestions. for a 6.7cf box just to make 12sqin port per cuft 80sqin thats means you will need 6-4in ports and having the small box you should tune to 32hz making them 26.85in long after displacment you will have just about 5.25cuft its a little small but it should sound better and get louder than with just the 3. if possible to gain a little air space you could have the ports stick out of te box a few inches. my box is 13.35cf tuned to 28hz with 174in of port area after displacment it just comes under 10 cu its loud and loves the lows. i have tried sealed and small ported as well and it needs the minimum port area or more.

[snb778 1]

anyone else...

could I just use 2x 6" aero's??

[snb778 1]

bump again....

still tryin to figure out how much port I even need for this sub....

can I use those cardboard tubes and just cover it in resin to make it solid?? vs. using PVC... I kinda want to make a 10 or 12" port

someone please help! i want to get this goin

[snb778 1]

ok, forget all the detailed crap since nobody wants to chime in...

6.7 cu. ft. 2x 4" Aero's... Tuned to 30 hz... How long do they need to be FOR THIS SUB..

FI-guys... feel free to help out or im just going to have to email ya

[snb778 1]

ttt... this is great

[snb778 1]

ok, so I have room to do 7.1cu. ft. after Displ. SO, if I wanted to do 3x 4" ports, how long do they need to be for 30Hz? I need 94cu.in. of port I think.

[rushnrun 14]

ok, so I have room to do 7.1cu. ft. after Displ. SO, if I wanted to do 3x 4" ports, how long do they need to be for 30Hz? I need 94cu.in. of port I think.

run two 6" about 21" long

or four 4" about 21" long

(the 6 inchers will give you more surface area) You can buy 6" areos that are 18" long the 18 inch length will change the tuning roughly 2hz and probably will go unnoticed by you.

if you're stuck on 3 4inchers go 12" long but I'd reccomend atleast 4 4's or 2 6's

[rushnrun 14]

btw the area you have with 2-6" is only 56.5in^2

3-4" is only 37.7in^2

[nick_19 1]

http://www.psp-inc.com/psp-inc.com/public_..._calculator.cgi

Help? or not?

[///M5 2,833]

You should have started this thread before buying a Q, it that driver isn't loud enough for you then it isn't even close to the right selection for your needs.