2 MJ-18's, 9 cubes net in trunk build

[Rashaddd 5,000+ posts]

i got a question and im not sure if its been covered, but did you mostly use glue to build your box? im getting ready to start my build and it looks like it will have to be in the trunk and i have always been skeptical about using just glue on a box.
especially building it in the trunk as i wont be able to get my clamps to it that easily. do you feel like it did a great job sealing all the joints together nicely?

Honestly, I probably skimped and cut corners alot, when I look back I wish I would've done a better job and I certainly will next time, but I was just dying to get music back in the car and have it functional. It still worked surprisingly well though...I have some baffle flex, but other than that the box doesn't flex hardly at all despite the fact that its 1/2" AND built with only glue (and poorly glued at that).

If you take your time and really try to get solid joints with just glue, I'm confident you won't have any problem getting a structurally sound box. I'm basing this off the fact that I didn't take my time or do a very good job, and I still have very satisfactory results //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

I guess numbers will tell better, but it definitely is a lot louder than they were sealed, and I consider this build a definite success //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[infamous_e46 5,000+ posts]

what kind of car ??? i am stressing out trying to figure out how to fit 8cubes in the accord

 

[Rashaddd 5,000+ posts]

what kind of car ??? i am stressing out trying to figure out how to fit 8cubes in the accord

2000 Mazda 626

Certainly not a gigantic trunk relative to some, its a decent size though. Biggest problem I run into with boxes is the max size I can fit through the opening is like 30w x 15h, and in doing so I am limited to around 15-18d as well because of the angle, even though the trunk can contain a box MUCH bigger than this, hell...even to fit 6 cubes sealed I had to build two separate boxes, and that was an extremely tight fit, ended up having build them slanted on top of it...

 

[Rashaddd 5,000+ posts]

Did a 143.2 @ 44-45hz legal

my car sounds a good few db's louder with the door open/window down, but doesn't meter any louder haha

Also pretty flat response from low 30's to high 50's, within ~1db from high 30's to mid 50's

single battery, amp grounded to the frame, flexing+leaky box, not enough port area, little over 1.5kw, I'd say its decent?

maintains a solid 140-141 on music all day

btw to give you an idea of what I mean by flexing box, if I put my weight into pushing on the baffle while playing a tone, cone excursion visibly changes by several mm's, so that's just an idea of how much it's affecting it...I'm now wishing I hadn't rushed the box as much lol but oh well

 

[ssackett 10+ year member]

^^ good meeting up with you today. Shit was loud and your score is not bad at all for no major electrical upgrades and 1500watts. Keep up the good work. Lets get that power doubled and that LMS 18 in there boyee!!

 

[MikeyB 5,000+ posts]

I say design another enclosure and use some 3/4, brace the shit out of it, and throw another port in your rear deck. Oh and take your time. //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif

 

[Rashaddd 5,000+ posts]

I say design another enclosure and use some 3/4, brace the shit out of it, and throw another port in your rear deck. Oh and take your time. //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif

Meh, I've already got plans and some equipment for next build, I'm confident there's another 2-3db in this equipment with a better quality enclosure/more port, but there really isn't room for it unless I put a hell of a lot more effort/time into it, so I'm just gonna leave it at that and move on haha. I've also learned my lesson on using too much sub and not enough box, not worth it, at least imo. I think this would do alot better with an optimal enclosure + decent port area, i mean comon lol 8 cubes and 50sq in for two 18's. Nonetheless it still looks sick having two 18's chillin back there haha

oh yea and thanks again scott for gettin me on the TL //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[ARSkemp 10+ year member]

nice score, especially for just 1500w and such a flat frequency response.

whats your plans for the next build?

 

[LDW3RD 10+ year member]

Nice score, good luck with the next build.

I like the wow that 2 18's in a small space gives.

pretty pimp build nonetheless. looking forward to the next one.

 

[MikeyB 5,000+ posts]

Meh, I've already got plans and some equipment for next build, I'm confident there's another 2-3db in this equipment with a better quality enclosure/more port, but there really isn't room for it unless I put a hell of a lot more effort/time into it, so I'm just gonna leave it at that and move on haha. I've also learned my lesson on using too much sub and not enough box, not worth it, at least imo. I think this would do alot better with an optimal enclosure + decent port area, i mean comon lol 8 cubes and 50sq in for two 18's. Nonetheless it still looks sick having two 18's chillin back there haha
oh yea and thanks again scott for gettin me on the TL //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Do the same style build just drop to some 15's or 12's.

 

[seedubs1 10+ year member]

Do the same style build just drop to some 15's or 12's.

I did basically the same things with some eclipse 15" TI's. Got real loud. No scores on the TL, but it was loud to the ear.

Next time use some L-brackets in conjunction with a good glue joint. When I ripped this thing out of my trunk, the 3/4 inch MDF is what broke. My glue joint was still in tact. A GOOD glue joint should be stronger than the MDF.

(This was all braced up and covered up. Just an idea of what you could do with some 15's or something like that, and you can see how you can use the L-brackets to help with keeping the MDF pieces compressed together to help you get a better glue joint.

 

[Rashaddd 5,000+ posts]

Got my new TL up and running today //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

found a 146.2 (could realistically hold a 145.5-146 for easily 30 secs straight, system isn't really under any extreme stress, I let it rip for 10 secs straight and it didn't drop even a tenth)

That's 3db up from my original score of a 143.2 iirc, from strengthening the box and stopping the baffle from flexing, and switching amps (only maybe a couple hundred watts extra)

Freq breakdown:

20hz - 138.2

30hz - 139.5

35hz - 143.8

40hz - 144.5

45hz - 146.2

50hz - 144.7

55hz - 144.0

60hz - 143.2

70hz - 141.9

80hz - 139.4

As you can see it's relatively flat considering a 36hz tuning and a box that's about 10-20% too small //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif, sounds great on all music

 

[mrogowski 5,000+ posts]

Friggin sweet man. You have solid output down low and that's all that matters //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[wasted ink 10+ year member]

Nice. Surprising, but nice. Now get that LMS Ultra going //content.invisioncic.com/y282845/emoticons/drool.gif.b5e863e893038027711d4402f340dad0.gif

 

[snb778 5,000+ posts]

ya know.. its really depressing when I think of this setup.....







Ports set and back dash fiberglassed



The shi tty part is the guy who built the boxes didnt know what he was doing with the Aero's, so it sounded like crap!! Although I didnt have a TON of power, it should have been louder

I can't believe you had all that flex in your vid, and only did a 143!! wtf??