car audio project

[GOVEHIX]

finally received my JL 12"W7 and JL 1000/1 amplifier, and wondering where should i place them. i am wondering does the rear door able to carry the 45lbs 12"W7? i mean, if it can't, i got to go with traditional box and place it in the rear cargo space.
and the fiberglass thing is hard to work with, once it mixed with resin, it became sticky, and wouldn't go away my gloves.

[kpaske]

I've got 2 x 12" subs and a large amp mounted to a fiberglass + MDF box in my rear door. It easily weighs over 50 lbs and I've had no issues with the door being able to handle the weight. The only problem I have is that I have to hit the switch for the door popper two or three times to get it to work, but that's probably an adjustment issue.

You can check out my web page for pics.

[VehiGAZ]

kpaske,

Check the pulley on the door popper system. Mine slid down a bit after initial installation, and I started having the SAME problem - the door not opening unless I held the popper button in for a couple of seconds.

Govehix, the door will be able to carry the weight of the subs, but the plastic interior piece (if that's what you were thinking of mounting the sub to) will not, and will provide no accoustics for the speaker, either. You need to build a sub box that will match the shape of the door and mount the box to it nice and sturdy.

[morgan-tec]

The W7 and amp are large components and that ub is a monster. I would build a correct mdf and fiberglass box for the cargo area if i were you. Make sure you give that sub the proper air space and it will scream.

[kpaske]

I managed to squeeze my large Orion HCCA 250 Amp and two twelves in the rear door. IIRC, each sub required a minimum of 1 cubic foot sealed air, and I squeezed just a little over that. I used some stuffing material inside to help increase the perceived volume, and my subs sound really nice. However, if I had to do it over again, I might consider mounting the amp elsewhere to get some more volume for each of the subs, or even using just one sub. I believe those subs can be mounted is as much as 3 cubic feet of air for competition grade systems.

I don't know what the volume requirement is for your JL 12, but you should easily be able to get about 2 cubic feet, which is enough to make most subs sound incredible.

[GOVEHIX]

according to the owner's manual, the recommended volume for the sealed enclosure is 1.375 cu ft; and for the ported enclosure is 1.75 cu ft.
i am still thinkin how to build the box, kpaske, can you tell me how you build yours? it's kinda hard to build a sealed box and mount it to the round door. (i couldnt get through your web site i don't know why.)

[kpaske]

Yeah, sometimes my router locks up, blocking access to my web page. It's back up if you want to try again.

Anyhow, since I was building a box with two seperate, sealed chambers, I used a solid piece of MDF running straight down the middle, from top to bottom as my starting point. I cut one edge so it lined up nicely inside the door, effectively splitting it in half. Then I built an MDF "frame" that went around the circumference of the outer edges of the door, and a flat board that the amp would later mount on. Once this rough frame was built, I stapled felt around the edges, creating a surface to lay my fiberglass on. It's probably hard to imagine what I'm talking about without seeing it... unfortunately I didn't take any pictures, but if you really are interested in duplicating the design, I'll try to explain it a little bit better and in more detail.

I also considered not using fiberglass at all -- the door would probably accept an "octogon" shaped sealed MDF box with a slanted front, and with this design you should probably not have much trouble squeezing 1.375 cu ft out of it.

[GOVEHIX]

Yeah, sometimes my router locks up, blocking access to my web page. It's back up if you want to try again.

Anyhow, since I was building a box with two seperate, sealed chambers, I used a solid piece of MDF running straight down the middle, from top to bottom as my starting point. I cut one edge so it lined up nicely inside the door, effectively splitting it in half. Then I built an MDF "frame" that went around the circumference of the outer edges of the door, and a flat board that the amp would later mount on. Once this rough frame was built, I stapled felt around the edges, creating a surface to lay my fiberglass on. It's probably hard to imagine what I'm talking about without seeing it... unfortunately I didn't take any pictures, but if you really are interested in duplicating the design, I'll try to explain it a little bit better and in more detail.

I also considered not using fiberglass at all -- the door would probably accept an "octogon" shaped sealed MDF box with a slanted front, and with this design you should probably not have much trouble squeezing 1.375 cu ft out of it.

kpaske, just come up with a question, did you put extra battery and capacitor to support your sub system?

[kpaske]

Nope, I'm using an Optima Blue Top battery and 0 guage wiring. I ran 0 gauge from the negative battery terminal to the block, then to the chassis ground, as well as 0 guage from the positive battery terminal to a distribution block behind the driver's seat. My alternator is stock. It seems to have plenty of juice for my two big amps, though I still plan to run a 0 guage from my alternator to my positive battery terminal sometime in the future. My lights dim a little bit sometimes when the system is REALLY thumping, but I've never had a problem starting or having my battery run out.

From what I understand, lowering the resistance by using really large wires helps quite a bit (often solving a lot of power issues). The key three points are the wires from the negative to block to ground and from positive to alternator.

[Child's Play]

Here's a link to my cardomain site that has picture of my JL 12" sub. I had it custom installed, and absolutly love it. This thing hits and I love the way it looks in the back door! Take a look and let me know if you have any questions.

Adam

Here's the link:

http://www.cardomain.com/ride/2074072

[GOVEHIX]

Here's a link to my cardomain site that has picture of my JL 12" sub. I had it custom installed, and absolutly love it. This thing hits and I love the way it looks in the back door! Take a look and let me know if you have any questions.

Adam

Here's the link:

http://www.cardomain.com/ride/2074072

oh my god! that's awesome, and that's exactly what i want it to be.
so is that just a flat board to hold the sub and the amp, or it's a sealed box? i am still confusing about how to mount it firm to the door. do you have any detail about your custom project? thanks a lot.

[Child's Play]

oh my god! that's awesome, and that's exactly what i want it to be.
so is that just a flat board to hold the sub and the amp, or it's a sealed box? i am still confusing about how to mount it firm to the door. do you have any detail about your custom project? thanks a lot.

Thanks for the compliment. I really like the way it is set-up and the way it sounds, these JL's really hit! The enclosure is a sealed enclosure that they custom molded with fiberglass into the rear door, along with a "notch" to mount the amp to the enclosure, while keeping it all small enough to mount behind the plastic door cover. I had to help them with ideas on mounting to the door. What we ended up with was using the spare tire "ring" (should be gold in color) and bolt to hold the enclosure to the back of the door. THis helps spread the weight over a greater surface area when closing the door! We applied adhesive/sealant to the tire "ring" and bolt to seal the bolt hole from leaking air. There is also a brace on the bottom of the enclosure to help support the wieght of the box. Hope this helps, it is hard to put into words what we all did. If you need anything else, let me know.

Adam

[GOVEHIX]

is your subwoofer the jl w6? what's the length of it? mine jl w7 has a 9.25" length, i just dont know what to do in order to place it nicely. the depth of the spare tire well is about 7", and no matter how i put the sub, it just dont sound right. any suggestion?

http://brocksrsxaudio.tripod.com/imagelib/sitebuilder/misc/show_image.html?linkedwidth=actual&linkpath=http://brocksrsxaudio.tripod.com/sitebuildercontent/sitebuilderpictures/w7rear.jpg&target=tlx_new

[GOVEHIX]

anyone knows what kinda powercable should i use? 2 gauge or 4 gauge? and what's really means? i am so new to all these things.thx

[psychos2]

it will not sound right when not it an enclosure. the mounting depth for that sub is 9.5" minimum.and as far as the power wire. the manual says:
"The 1000/1's “+12 VDC” and “Ground”
connections are designed to accept 4 AWG power
wire. 4 AWG is the only recommended
power wire size for this amplifier.
If you are installing the 1000/1 with other
amplifiers and wish to use a single main power wire,
use 2 AWG or 1/0 AWG main power wire
(depending on the overall current demands of all
the amplifiers in the system).This 2 AWG or
1/0 AWG power wire should terminate into a
distribution block mounted as close to the amplifiers
as possible and should connect to the 1000/1 with
4 AWG power wire."
i would use at least 2 gauge wire and use a distribution block to convert to 4 gauge.it also says to use 100 amp fuse:
"FUSE REQUIREMENTS
It is absolutely vital that the main power
lead to the amplifier(s) in the system be fused
within 18 inches (45 cm) of the positive battery
post connection.The fuse value at each power
wire should be high enough for all of the
equipment being run from that power wire.
If only the 1000/1 is being run from that power
wire, we recommend a 100A ANL (large bladetype
fuse pictured below) be used.
No fuse is required directly before the amplifier
power connection. If one is desired at this
location, we recommend the use of a 100A ANL
fuse for each 1000/1." shawn