trying to get four L5 8" subs tuned to 36 hz

[charlesarms85 10+ year member]

Hello, I am needing a little help with a box i am building. I am going to be putting four 8" L5 subwoofers in a single cab 08 f150 with the pocket doors. Ive measure the space and its 51w, 22h, and 6d and that should put me around 3.5 cu. f.t before disp. My question is this, I want to do 3-4 round ports beause ive heard they are more acurate. Can someone help me please?

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[4OZGLOVES 10+ year member]

Hello, I am needing a little help with a box i am building. I am going to be putting four 8" L5 subwoofers in a single cab 08 f150 with the pocket doors. Ive measure the space and its 51w, 22h, and 6d and that should put me around 3.5 cu. f.t before disp. My question is this, I want to do 3-4 round ports beause ive heard they are more acurate. Can someone help me please?

if you do 3-4 ports they most likely will be to long to fit in your box. If i was in your situation I would do one 6" aero. I think that would be much easier and It should be enough port area for 3.5 cubes.

 

[charlesarms85 10+ year member]

how would i do an aero port? Ive never done round ports before? Or point me in a direction to calculate and be educated on aeroports?

 

[DBBOOM 10+ year member]

PORT Size Calculations and Formulas for WOOFER and Subwoofer BOXES

http://psp-inc.com/tools.html

 

[charlesarms85 10+ year member]

Thanks, so 6" round port about 12.5" should be enough to tune the box to 36 hz on 3.5 cu. ft. after disp? I figured roughly .2 cu. ft. per sub disp puts me around 1.0 cu. ft. disp and building the box at 4.3 cu. ft. (52w, 22h, 8.5d) should do the trick

 

[Ronny 10+ year member]

*eek* I gurantee each sub does not hold .2cubes of displacement. You should be able to find the exact figures on the webiste or call 'em.

 

[charlesarms85 10+ year member]

Ok.... so 49.1 cu. inches PER 8" sub x 4 subs = 196.4 cu. inches converted to cubic feet = 0.113 cubic feet.... am i on the right track here?

 

[Slo_Ride 5,000+ posts]

*eek* I gurantee each sub does not hold .2cubes of displacement. You should be able to find the exact figures on the webiste or call 'em.

x2 i'd guess .1 at the most

 

[charlesarms85 10+ year member]

So, all four subs will take up only .113 cu. ft.? So as long as I build the box, lets say, at .8 cu. ft. per sub = 3.2 cu. ft. total, so pretty much build the box to 3.5 cu. ft. and I should be good? Sorry i am being so thorough, just wanna get it right the first time around.

 

[RAM_Designs 5,000+ posts]

You don't have enough room, 51" x 22" x 6" using 3/4" MDF only nets you 2.64ft^3 before displacements...maybe just run sealed or use just a pair of them.

 

[charlesarms85 10+ year member]

Just measured again..... 51w, 23h, 7.5

 

[azphat12 10+ year member]

Just out of curiosity, with such a tight fit and all. Have you explored the option of a box in the bed of the truck ported to the cab? I had 4 12's in an S10 done this way. Either you lose your cabin room, or you lose your truck bed room.... I believe it was a bandpass box they built for me...was several years ago.

 

[DBBOOM 10+ year member]

L7 8"s do better with ~1cu.ft each on a ported build. Build the box to 4.5cu.ft GROSS, after bracing and sub displacement you will be at 3.8-4cu.ft. . Do some simple geometry and find the internal volume. Use the PSP calculator i linked above. If you don't have that much room..........use two or go sealed. Simple enough?

 

[charlesarms85 10+ year member]

Your right man, SPL needs 1.0 cu ft, but I don't want ALL spl..... i need it to sound decent on music too.

 

[charlesarms85 10+ year member]

Just out of curiosity, with such a tight fit and all. Have you explored the option of a box in the bed of the truck ported to the cab? I had 4 12's in an S10 done this way. Either you lose your cabin room, or you lose your truck bed room.... I believe it was a bandpass box they built for me...was several years ago.

I would, but man, sqeezing a loud set up in a decent size space if fine with me. I have the "pocket doors" on my reg cab so my reg cab is ALOT bigger than most reg cab trucks.