*Ford F-150* (JL build)

[CGienapp1]

go buy a sheet of wood, we will help you with box design.

you can thank us later.

Is there any way to modify my current box?

How many inches of port area am I at with 1.5"x22.25"?

And doesn't the entire length and bends in the l-vent give it "more" port?

[poorboy6977]

Why don't you just try their advice? All its gonna cost you is wood and time. I thought I knew a lot about car audio until I started reading these forums....boy was I wrong. I don't post much but I read a lot daily and take notes. Because of this site I can't quit building different boxes and changing my tuning and ports. Since my first box I've picked up 5.7db on the tl and I'm not done yet. Box has a lot to do with it man. You can't say its the best until you have something to compare it to. Its an addiction man. Give it a try, what could it hurt? What if they're right and u got a couple more db there?? Good luck

[J-Lane]

If I'm not mistaken you should have approximately 12-16 square inches of port area per cubic foot. If you have approx. 4 cu. ft. per sub (assuming internal space) you would need 48-64 square inches of port area. So if your port was 4 inches wide and 16 inches tall that would be perfect. The port length is what affects the tuning. Your port area is 1.5 x 22.25 = 33.375 (way too small). If you are willing to take advice from the people on SMD they will be willing to help. I have learned a ton in just the short amount of time I have been visiting this web site. Keep in mind that most of the guys on here know ten times more than any guy working at your local car audio shop. You could probably build yourself a decent enclosure for pretty cheap. You could sell that box you have on craigslist and use the money for a few sheets of MDF. Ask people on here for some suggestions on enclosure sizes and you would be amazed at what those subs are really capable of. Good luck and I hope you take the advice of the guys on here. You won't be disappointed.

[CGienapp1]

If I'm not mistaken you should have approximately 12-16 square inches of port area per cubic foot. If you have approx. 4 cu. ft. per sub (assuming internal space) you would need 48-64 square inches of port area. So if your port was 4 inches wide and 16 inches tall that would be perfect. The port length is what affects the tuning. Your port area is 1.5 x 22.25 = 33.375 (way too small). If you are willing to take advice from the people on SMD they will be willing to help. I have learned a ton in just the short amount of time I have been visiting this web site. Keep in mind that most of the guys on here know ten times more than any guy working at your local car audio shop. You could probably build yourself a decent enclosure for pretty cheap. You could sell that box you have on craigslist and use the money for a few sheets of MDF. Ask people on here for some suggestions on enclosure sizes and you would be amazed at what those subs are really capable of. Good luck and I hope you take the advice of they guys on here. You won't be disappointed.

Alright. Thanks. I guess I was led in the wrong direction by a 20 yr vet con-artist then.lol I want to finish the rest of the system before I go and do that though.

But just so I can start designing one. I can only work with the dimensions my box is already or smaller unless I modify the back rest:

24" height

36" width

18" deep

..can anyone turn that into a box design?

[CGienapp1]

If I have about 3cuft per sub and 33" of port..wouldn't I be just shy of having enough following the 12-16" "rule of thumb". 12"minimum of port per 1cube volume. 12x3=36 and I have 33. Maybe I'm wrong again but seems close to me.

[CGienapp1]

Why don't you just try their advice? All its gonna cost you is wood and time. I thought I knew a lot about car audio until I started reading these forums....boy was I wrong. I don't post much but I read a lot daily and take notes. Because of this site I can't quit building different boxes and changing my tuning and ports. Since my first box I've picked up 5.7db on the tl and I'm not done yet. Box has a lot to do with it man. You can't say its the best until you have something to compare it to. Its an addiction man. Give it a try, what could it hurt? What if they're right and u got a couple more db there?? Good luck

Thanks man and ya imma try it out. I'll prolly keep this box around in case I screw up but I could use another 5 DB. I don't think my ears could.lol That is , however, my goal..not wanting to crank it.lol

[dwright27]

If I have about 3cuft per sub and 33" of port..wouldn't I be just shy of having enough following the 12-16" "rule of thumb". 12"minimum of port per 1cube volume. 12x3=36 and I have 33. Maybe I'm wrong again but seems close to me.

12 - 16 square is just a rule

Of thumb and is an excellent starting point.

Port area is determined by the width and height of your port. Therefore your current port setup "1.5x22.x" would equal 33 square inches of port.

33/4 = ( assuming thats what your box is now ) 8.25 square inches of port per cubic foot.

So you have about half the port area needed. I personally like to start at a 20 square inch per cube ratio, and then shrink the port down.

[splzx3]

just make a new e'ff box stop trying 2 mod the box u have

it will save u tym and alot of bull shit with it

if u want i will help u just pm ur LxWxD and all the info about ur subs and shit

[CGienapp1]

If I have about 3cuft per sub and 33" of port..wouldn't I be just shy of having enough following the 12-16" "rule of thumb". 12"minimum of port per 1cube volume. 12x3=36 and I have 33. Maybe I'm wrong again but seems close to me.

12 - 16 square is just a rule

Of thumb and is an excellent starting point.

Port area is determined by the width and height of your port. Therefore your current port setup "1.5x22.x" would equal 33 square inches of port.

33/4 = ( assuming thats what your box is now ) 8.25 square inches of port per cubic foot.

So you have about half the port area needed. I personally like to start at a 20 square inch per cube ratio, and then shrink the port down.

Don't take this wrong because I know they are "the same" but do you prefer round or square ports? I was told square are easier to tune and If I started big I'd just have to make blocks to reduce the area unlike a round port.

[dwright27]

[quote name=dwright27' date='15 December 2010 - 12:37 PM' timestamp='1292441831'

post='1313317]

If I have about 3cuft per sub and 33" of port..wouldn't I be just shy of having enough following the 12-16" "rule of thumb". 12"minimum of port per 1cube volume. 12x3=36 and I

have 33. Maybe I'm wrong again but seems close to me.

12 - 16 square is just a rule

Of thumb and is an excellent starting point.

Port area is determined by the width and height of your port. Therefore

your current port setup "1.5x22.x" would equal 33 square inches of port.

33/4 = ( assuming thats what your box is now ) 8.25 square inches of

port per cubic foot.

So you have about half the port area needed. I personally like to start at a 20 square inch per cube ratio, and then shrink the port down.

Don't take this wrong because I know they are "the same" but do you prefer round or square ports? I was told square are easier to tune and If I

started big I'd just have to make blocks to reduce the area unlike a round port.

I prefer slot ports. Round ( aero ) ports are more efficient, but easier to tune IMO.

Yes all you would have to do in most cases is just make blocks. And that's why I like to start on the big side.