zigzags jeep grand cherokee build

[hispls 5,000+ posts]

ya i like the 6.5s way better then the 6x9s, the 6.5 sounds so good and have about the same level of bass as the 6x9s. and i also would have need a baffle anyways since these mids at **** near 3 inches deep and wouldnt allow the window to roll down all the way otherwise.
im not to sure what im going to do as for upgrading woofers im kinda thinking about going with 18s, i was talking to ram and i have enough room for 14 cubes if i use areo ports and use up as much space as possible in the back. but its a toss up betweens the 15s and 18s. i would kinda like to keep it below the window and not have a huge *** box in the back, but i want to get LOUD lol.

IMO the only thing wrong with 6X9 is there really aren't any good quality ones (possibly a few, but not compared to the selection in 6.5" components).

Well, you've got about 8 or 9 cube net (wtih adequate port) if you want to stay below the window line and that's subs and port up. Good for a pair of 15's or 3 12's. I'm looking to get a pair of 18's going this year and the box is going to have to be very tall and from my experience crowding the port to close to the roof isn't so hot. Definitely subs and port firing forward is a disaster.... as tempting as it may seem avoid at all costs!

 

[splwj47 10+ year member]

IMO the only thing wrong with 6X9 is there really aren't any good quality ones (possibly a few, but not compared to the selection in 6.5" components).
Well, you've got about 8 or 9 cube net (wtih adequate port) if you want to stay below the window line and that's subs and port up. Good for a pair of 15's or 3 12's. I'm looking to get a pair of 18's going this year and the box is going to have to be very tall and from my experience crowding the port to close to the roof isn't so hot. Definitely subs and port firing forward is a disaster.... as tempting as it may seem avoid at all costs!

well the box for the 18s would be 31dx42wx25h so i would have about 8 inches from the roof or 6 inches from the side of the vehicle and maybe 4 inches from the rear. so i dont know where would be the best spot for the ports ram said to use 3 8 inch aero ports. subs will be up just need to figure out where the ports will go. if i got with 15s then i will go subs up port to the side most likely maybe to the rear.

 

[hispls 5,000+ posts]

well the box for the 18s would be 31dx42wx25h so i would have about 8 inches from the roof or 6 inches from the side of the vehicle and maybe 4 inches from the rear. so i dont know where would be the best spot for the ports ram said to use 3 8 inch aero ports. subs will be up just need to figure out where the ports will go. if i got with 15s then i will go subs up port to the side most likely maybe to the rear.

You may have issues with closing the rear hatch with a box that deep and tall. If you're only measuring on the floor you should double check all the angles going up and if you have the window that opens on the back you'll run into the pistons for that. 8" from the roof is bare minimum for 8" ports firing up and it may not be optimum and may make the ports act longer... still your best bet if you go that way.

The other thing that is tough going that high is that with the box in there isn't enough room to mount the subs (really ***** if your subs weigh 90 pounds ea) so you may have to mount the subs and find a few guys to try to wrestle the box in with the subs mounted.

 

[splwj47 10+ year member]

You may have issues with closing the rear hatch with a box that deep and tall. If you're only measuring on the floor you should double check all the angles going up and if you have the window that opens on the back you'll run into the pistons for that. 8" from the roof is bare minimum for 8" ports firing up and it may not be optimum and may make the ports act longer... still your best bet if you go that way.
The other thing that is tough going that high is that with the box in there isn't enough room to mount the subs (really ***** if your subs weigh 90 pounds ea) so you may have to mount the subs and find a few guys to try to wrestle the box in with the subs mounted.

ya i measured the hatch opening and that is why i can only go 25 inches high with 42 wide or it wouldnt fit in the back. i think i may build the box out of birch to try and save a few pounds. but im not sure which way im going yet with the 15s or 18s, the 15s is more or a better choice for room and mounting plus weight. and im not sure if i am willing to give up all the space and added weight for the 18s, but i want loud.

 

[hispls 5,000+ posts]

ya i measured the hatch opening and that is why i can only go 25 inches high with 42 wide or it wouldnt fit in the back. i think i may build the box out of birch to try and save a few pounds. but im not sure which way im going yet with the 15s or 18s, the 15s is more or a better choice for room and mounting plus weight. and im not sure if i am willing to give up all the space and added weight for the 18s, but i want loud.

From my experience you will get only marginal gains from 18's in too small a box crammed in vs. 15's in an optimum box with enough room for ports to function properly. A pair of 18's = cone area of 3 15's and real world gain would be 1db and small change on a good day....barely audible.

 

[splwj47 10+ year member]

got my big 3 done today. didnt take much wire only about 9 feet and could have used probably 2 less.

didnt get any pics of it installed as it was kinda startin to rain.

 

[splwj47 10+ year member]

From my experience you will get only marginal gains from 18's in too small a box crammed in vs. 15's in an optimum box with enough room for ports to function properly. A pair of 18's = cone area of 3 15's and real world gain would be 1db and small change on a good day....barely audible.

well the box for the 18s would be 14 cubes so the 18s will have enough space for them to perform like they should. my current box is 38 inchs wide so addint another 2 inches to each side for the new box do u think there would be enough area for the port.

 

[hispls 5,000+ posts]

If you want to port out the side you won't want the box more than 34" wide IMO. Crowding the port into the side wall looses db's. Seriously I don't know if you have more than 28" front to back if you go up 24". Seat backs angle in and the top half of the lift gate angles in as well. Personally I'd mock it up with cardboard or something before you go cutting any wood and drawing up blueprints unless you're good at changing your box on the fly in which case just dry-fit the pieces before you screw and glue and be ready to alter dimensions slightly. I got too greedy with my last box and couldn't lift the back seats all the way.

 

[Mr. Slate 10+ year member]

Crowding the port into the side wall looses db's

Not in all cases, I've seen some vehicles gain.

 

[splwj47 10+ year member]

If you want to port out the side you won't want the box more than 34" wide IMO. Crowding the port into the side wall looses db's. Seriously I don't know if you have more than 28" front to back if you go up 24". Seat backs angle in and the top half of the lift gate angles in as well. Personally I'd mock it up with cardboard or something before you go cutting any wood and drawing up blueprints unless you're good at changing your box on the fly in which case just dry-fit the pieces before you screw and glue and be ready to alter dimensions slightly. I got too greedy with my last box and couldn't lift the back seats all the way.

so im thinkin i might just do subs up port up, the meter doesnt really matter to me since it will probably never be on one , but i want it to be loud and have them hit really hard, so i might go subs up port back also. i kinda want the box to go all the way across the back for looks so port to the side wouldnt work. im thinkin im just going to go with 15s since 18s would just be so much more work and its easier on my wallet. ill do 8 cubes, kerfed port, with 120 inches or port. all ur advise is very appreciated. thanks.

 

[hispls 5,000+ posts]

Not in all cases, I've seen some vehicles gain.

I expect so. Of course it's easier if you have a box that's small enough that you can test all angles and distances from walls. If you plan to build a box that'll barely fit in the space available and don't have room to move it if it doesn't work IMO it's not advisable.

so im thinkin i might just do subs up port up, the meter doesnt really matter to me since it will probably never be on one , but i want it to be loud and have them hit really hard, so i might go subs up port back also. i kinda want the box to go all the way across the back for looks so port to the side wouldnt work. im thinkin im just going to go with 15s since 18s would just be so much more work and its easier on my wallet. ill do 8 cubes, kerfed port, with 120 inches or port. all ur advise is very appreciated. thanks.

Subs up and port up sould be good for listening and you can use your whole width and depth and keep height right around the window line and end up with 8 cube net or so. Port on the side and I'd shoot for more port area and 37-40hz tuning. That box I posted with the 3 12's sounded fantastic. IIRC port was around 120-140"^2 (not counting the flare). Well worth the extra wood to double baffle and flush mount the woofers if you can.

 

[splwj47 10+ year member]

I expect so. Of course it's easier if you have a box that's small enough that you can test all angles and distances from walls. If you plan to build a box that'll barely fit in the space available and don't have room to move it if it doesn't work IMO it's not advisable.


Subs up and port up sould be good for listening and you can use your whole width and depth and keep height right around the window line and end up with 8 cube net or so. Port on the side and I'd shoot for more port area and 37-40hz tuning. That box I posted with the 3 12's sounded fantastic. IIRC port was around 120-140"^2 (not counting the flare). Well worth the extra wood to double baffle and flush mount the woofers if you can.

ya i was going to do double baffle and flush mount, so u dont like subs up port back idea? why tune so high, i was thinkin 32-34hz range i want it to hammer the lows. would it still hit real hard with subs up port up. i more or less want them to get down and dirty over sounding good, but still want them to sound decent. if ya get what i mean lol.

 

[hispls 5,000+ posts]

ya i was going to do double baffle and flush mount, so u dont like subs up port back idea? why tune so high, i was thinkin 32-34hz range i want it to hammer the lows. would it still hit real hard with subs up port up. i more or less want them to get down and dirty over sounding good, but still want them to sound decent. if ya get what i mean lol.

Port back is terrible mostly because it's such an inefficient use of space. Assuming you want 6 or 8" between the port and the wall, Takc 6" off the 42" side and you lose a load of volume for minimal gain (difference between porting back, side, and up is really not that dramatic if you're not chasing numbers).

Tuning 37 is pretty low. IMO 45hz and up is tuning high. Really depends on the subs you wind up getting, but I find tuning @ 30hz you have a peak there, and a small peak @ 55hz with a sharp rolloff above that. SO your slowed music with notes below 40hz sounds great, but anything more dynamic just sounds un-natural.

IDK if you have a meter or way to see what frequency is what, but I suspect you rely on 50-60hz much more than you think and what you think is super low is probably 35-37. AND tuning @ 37 you should still be able to play down to 30hz well enough.

Get some test tones and see what 20-30hz really sounds like and if you feel like you're really missing the boat without that being your loudest notes go head and tune 28-32hz. I'd reccomend using more port area than you need, tuning to 37, then adding more layers to your port or extending it on the back to tune lower if you decide you really need to go there.

Then again, it'll depend on your subs as well, but I've tested a pretty good variety and I find that's the best compromise between good impact and low extension.

 

[splwj47 10+ year member]

Port back is terrible mostly because it's such an inefficient use of space. Assuming you want 6 or 8" between the port and the wall, Takc 6" off the 42" side and you lose a load of volume for minimal gain (difference between porting back, side, and up is really not that dramatic if you're not chasing numbers).
Tuning 37 is pretty low. IMO 45hz and up is tuning high. Really depends on the subs you wind up getting, but I find tuning @ 30hz you have a peak there, and a small peak @ 55hz with a sharp rolloff above that. SO your slowed music with notes below 40hz sounds great, but anything more dynamic just sounds un-natural.

IDK if you have a meter or way to see what frequency is what, but I suspect you rely on 50-60hz much more than you think and what you think is super low is probably 35-37. AND tuning @ 37 you should still be able to play down to 30hz well enough.

Get some test tones and see what 20-30hz really sounds like and if you feel like you're really missing the boat without that being your loudest notes go head and tune 28-32hz. I'd reccomend using more port area than you need, tuning to 37, then adding more layers to your port or extending it on the back to tune lower if you decide you really need to go there.

Then again, it'll depend on your subs as well, but I've tested a pretty good variety and I find that's the best compromise between good impact and low extension.

im going to be going with 2 IA death penaltys, i dont have a meter and dont think anyplace around here has one either. theres no comps or nothing up here so that why i wont be chasing numbers, i just want loud and hard hitting to me since that is that matters. so should i go 140-160 for port area. IA recomends 3-5 cubes and 55-80 inces of port per woofer.

 

[hispls 5,000+ posts]

im going to be going with 2 IA death penaltys, i dont have a meter and dont think anyplace around here has one either. theres no comps or nothing up here so that why i wont be chasing numbers, i just want loud and hard hitting to me since that is that matters. so should i go 140-160 for port area. IA recomends 3-5 cubes and 55-80 inces of port per woofer.

Pass me some TS parameters on those subs and I'll compare them to what I've tested in my jeep when I have a minute.