Kicker L7 12 box design

[ludeboost98]

I'm trying to design a vented enclosure to fit in my car but I am running into space issues . I looked at the factory specs of the subs and it gives two vented box sizes 1.75 and 3.25 . I can't acheive 3.25 and I dont want to really go as small as 1.75 . However I can obtain 2.5 . My main problem lies in port size . Both of those two box recommendations have different size ports and I dont know how to figure what is required for my application . Yea , I know I could just do a sealed enclosure buuut , I dont want to sooooo, here I am. Help please !

[Bfowler]

the best enclosure for a L7 is a metal cylinder

[ttocs]

I always recomended that for the explode line. They never hit as hard as they did by throwing them from 5 ft away into that enclosure but really prefered a dumpster..

I too have never been a fan of kicker. Big woofers, big boxes and big power needed to get them rockin, not sure I would recomend a small box for them. If you do not know your port length remember that it will take up space in the box and lower the amount of space you have.

[00goobs]

I made a 3.5cuft ported enclosure for 2 15" type-Rs on a 97 Prelude. It barely fit, but can be done without fiberglass. You could even fit a CD case in the trunk when done, hehehe... If you are creative, you could get 4 cubes with a 2-piece box or fiberglass.

Also, not much love for squares here, but I think my 2 12" L5s get very low in a 3.5cuft ported box. They play very low, but my 2 10" JLw3s in a sealed box seem way louder and cleaner. I bottomed out my L5s with 2 ZX600Tis and decided on the JLs for space issues.....

That tin can enclosure is pretty funny.....

[ttocs]

I would hope they would go low in a big box like that but also would happily swap jl 10s for a kicker (GOTTA SAY COMP) 12s.

I do want to appaud you for not adding the comp as I think it been at least a decade since I heard a kicker fan say kicker with followed by comp.........

[00goobs]

I would hope they would go low in a big box like that but also would happily swap jl 10s for a kicker (GOTTA SAY COMP) 12s.

I do want to appaud you for not adding the comp as I think it been at least a decade since I heard a kicker fan say kicker with followed by comp.........

Hehehe, they weren't loud, so I went low with the enclosure and they were free...

[ttocs]

see thats what I mean. if the box was good for them the zx600 should be enough power to drive a good set 12s but kickers just need soooo much more power to get them loud and clean. Not sayin it can't be done there are plenty of kicker systems out there that slam but how much more power are they pushing over someone with JL or PG 12's? The amps also seem to be inefficient as they draw alot of volts/amps to make big wattage. Inefficient is the best way I could describe their products and by the time you match their amp to their woofers you have spent more then you could on alot of other lines.

[ludeboost98]

Thanks for the completely irrelevant responses . Hey , I know peole have thier opinion and favorites but , I'm asking for technical expertise . I would go with other subs ,If i had them, but this is what I have . I have no problem with building a fiberglass enclosure , but what I was asking is how to calculate for a port and its proper tuning . This is the second time I asked for specific information and all I got was a bunch of grief about the equipment I am using . As far as the power? I am running them off of a zx1200.1 , PLENTY of power thanks

[Bfowler]

easy mang, the internet is bad at conveying sarcasm and jokes.

this is the port calculator i generally use.

http://www.the12volt.com/caraudio/boxcalcs.asp#por

the kicker specs for volume are between 1.75 and 3cf

so using those volumes, you can plug that, plus the port diameter you are aiming for, and get a length from the calculator

[Bfowler]

i just found their 2006 manual also, this is the box they recommended:

3.25 cf (total

3" by 13.25" by 14.5" long port

so plugging that into the calculator, that puts it at about 41hz.

then, you can increase the length to drop it to the frequency you actually want

[audiophyle_247]

I think its comical the old Solobarics were designed for tiny boxes, but these squares need huge boxes.

Seems to me you need to make the box as big as you can live with, and tune the port for whatever volume you come up with.
Bfowler's link is pretty good, and this is a calculator I use for quick stuff. http://www.carstereo.com/help/Articles.cfm?id=31

When you plan out the box remember you need to calculate the interior volume, its amazing how often people do not subtract the wood from the volume.
You need to also keep in mind the port takes up space, and the air inside the port does NOT count as internal volume, so when you plan out a port diameter, remember to add the wood displacement on top of that and subtract the entire volume from the box volume.
Quick example, say your overall box has 2.5cuft and the port (with its walls) takes up exactly .5cuft, the end result is a 2cuft box with .5cuft of porting.
If you tuned the port counting on 2.5cuft it will not come out right, and the actual freq of the port will be much higher than you planned.

Be prepared to spend a lot of time scribbling ish on paper with a calculator in your hand, I can easily spend hours trying to plan out a box if I need to fit it in a specific location.

[lukeman269]

Just do a 2.75" wide by 13.25" height by 28" long. That will work out well. Those L7's can hit crazy hard in a ported box. My brother had one only on 300 watts and it hammered. Wasn't worth crap in the sound quality area, but SPL was insane. Good luck man!

[Bfowler]

I think its comical the old Solobarics were designed for tiny boxes, but these squares need huge boxes.

well a square does have much more cone area then a circle

[smgreen20]

I did the 1.75 for a gen 1 S12L7 at 450 watts and in a '94 Bravado ddid a 141.1 dB and sounded very good surprisingly.