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I've had waaaay too many inquiries about a subwoofer enclosure that keeps the trunk usable and still sounds great. I've decided that I needed to make something that would cater to all of you who put stuff back there. Recently a member and I had been talking about it seriously and I think I've come up with a plan.

You all have a black plastic tool holder under the rear trunk carpet that lays over and inside the spare tire. The measurements of this area are 12.75" diameter at the bottom and 14.75" diameter at the top. Please correct me if I am wrong on either of those as it's very important I get them right and since I don't have an IS300 anymore I can't verify these for myself. :(

The idea is that we'd need to build a cylinder that allows a subwoofer to be mounted, recessed, into it and have it fit in that area that sits in the tool kit that is in the spare. Yeah, bitchin...takes up no trunk space. I'd recess the sub a bit so it wont hit the trunk floor. Basically, you'd connect your wires and it would drop right in. If you mounted your amp on the rear seat back, up and out of the way, it would be hard to even see that you had a subwoofer back there.

What do you all think? Should I go for it? How many of you would be interested? I think I have almost everything worked out but I'm waiting till I've ironed out all the details to actually build anything.
 

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I can get you measurements later this afternoon.

I don't think there is a huge market for it though. If you do it, if would be a really good idea to use the factory tire hold down to secure the enclosure.

Plus you can run a 12 IB through the ski pass and only take up about 2" of depth over the hump back there...only 14" wide and 14" tall. And no weight of the enclosure.
 

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Discussion Starter · #3 ·
I can get you measurements later this afternoon.

I don't think there is a huge market for it though. If you do it, if would be a really good idea to use the factory tire hold down to secure the enclosure.
I disagree good sir. I would be willing to bet that over 90% of the people who drive IS300's would be significantly opposed to the work a REAL IB install would entail. Sealing off the entire trunk from the cabin area would be a lot of work as opposed to just dropping in an enclosure into the spare. It would require the removal of NOTHING and it wouldn't need anything to secure it, trust me.
 

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I would be very interested in this being that I am wanting a setup that doesnt take up alot of space. I could even supply pics or measurements for the sportcross owners.
 

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It would have to be cost effective. I can do a glass enclosure that sits down over the wheel for about $200 and bolt up using the tire bolt down. I could do one for a 15 taking up the whole well for a little more.

There is a tad over 1.75 cubic feet in the tirewell without the spare tire in it. I would have to do some measuring to see how much airspace there is with the tire in the well.

But there really isn't THAT much work to seal up a trunk for iB use. You would want to seal around the baffle and the two large holes in the back of the seat. Depending on if you were keeping the rear speakers, you could take them out and seal those holes up too. Then there are the holes on the bottom of the trunk opening that should be silconed up too. Wouldn't take 15 minutes to seal everything up.
 

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Discussion Starter · #8 ·
It would have to be cost effective. I can do a glass enclosure that sits down over the wheel for about $200 and bolt up using the tire bolt down. I could do one for a 15 taking up the whole well for a little more.

There is a tad over 1.75 cubic feet in the tirewell without the spare tire in it. I would have to do some measuring to see how much airspace there is with the tire in the well.

But there really isn't THAT much work to seal up a trunk for iB use. You would want to seal around the baffle and the two large holes in the back of the seat. Depending on if you were keeping the rear speakers, you could take them out and seal those holes up too. Then there are the holes on the bottom of the trunk opening that should be silconed up too. Wouldn't take 15 minutes to seal everything up.
You're lying to yourself if you think that's a 15 min job. The rear deck is full of holes. Not to mention the rear seat back is too.

Either way, fiberglassing the spare tire well defeats the purpose of this project. I'm wanting to build a 100% stealth box, and keep the spare in the car. You'd hate to need that shit and not have it!
 

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No, it wouldn't take long at all. I've done a few cars in my day...been professionally installing for about 7 years now. While maybe not literally 15 minutes, it wouldn't take very long at all. The rear deck can be filled with expanding foam and the back of the seat could be taking care of with a couple pieces of damping material. So, maybe 10 minutes if you want the quick and dirty.

I'm saying I could do one enclosure for either a ported 12 or a sealed 15 that took up the whole tire well, or another type that would drop in over the spare tire for probably a sealed 12 depending on air space. Both fiberglass construction with an MDF top. Both could be secured using the bolt that holds down the spare tire. There really isn't a great way to secure the enclosure and be able to gt the tire out quickly.
 

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I kinda like the fact that it comes thru the carpet. Is there any way I could simulate something like that with ur box?
 

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You would have to build it up flush to that height or make a false floor. With the speaker coming through the carpet it would defeat the purpose of easy in/easy out for access to the spare tire since everything would be connected. Or, you could cut a hole in the carpet and tuck it around the speaker.
 

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Discussion Starter · #12 ·
There really isn't a great way to secure the enclosure and be able to gt the tire out quickly.
I beg to differ my friend. You just aren't thinking outside the box. ;)

I kinda like the fact that it comes thru the carpet. Is there any way I could simulate something like that with ur box?
That would make things a ton easier as far as depth requirements go. For most people they'd want the sub totally hidden and protected by the floor. To do like that other guy had you'd just need to cut the a hole in the floor and use a grill for the speaker. The grill would have to be installed by yourself obviously.
 

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For everything to sit flush with the spare, there is about .68 cubes inside the spare tire. Roughly 16.5" inside to inside and about 5.5" deep. Raise it up to 6.5" deep and you get .80 cubes gross. The only way to get those volumes would be use fiberglass for the sides and bottom.

The volume inside the black holder thing that goes inside the spare is about .4 cubic feet.

Now, the entire tire well has a touch over 3 cubic feet in it to make it sit flush with the trunk floor.
 

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Discussion Starter · #14 ·
Yeah, I think we can get a shallow mount inside the back holder thing. Even if the box was a tad small the user could just EQ up the bottom a little and it would be perfect.
 

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Problem with a lot of shallow subs is they have no excursion. So boosting the EQ may not work that well.

However, if they did have good excursion, the better solotion would be a Linkwitz Transform. Not too hard to build and would go line level infront of the sub amp. Does what the EQ can not do. But also adds more complexity in the mix.

What sub are you thinking would work in the space?
 

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I'd be willing to give it a shot... although I just finished up my sub install for good.

Only problem I see is that there will be a lack of bass because of the cardboard covering the sub, then the rubber mat on top of that... seems like the low's would suffer...
 

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Discussion Starter · #17 ·
Problem with a lot of shallow subs is they have no excursion. So boosting the EQ may not work that well.

However, if they did have good excursion, the better solotion would be a Linkwitz Transform. Not too hard to build and would go line level infront of the sub amp. Does what the EQ can not do. But also adds more complexity in the mix.

What sub are you thinking would work in the space?
True unless you were using an exceptionally good shallow mount. I think you know which one I'm talking about too. I've been told the production has just begun on those ;)


I'd be willing to give it a shot... although I just finished up my sub install for good.

Only problem I see is that there will be a lack of bass because of the cardboard covering the sub, then the rubber mat on top of that... seems like the low's would suffer...
Think about it this way, with your subs in the trunk just in a normal box they already have to fight their way through the back seat partition, cover, rear seat and MLV (mass loaded vinyl) that covers the rear seat back. I think a piece of carpet should be the least of your concerns.

If you really wanted to poke the sub face through the carpet the best bet would be a Sound Splinter RLi-10. You wont need to EQ at all to get the proper sound and it will fit perfect in that small box.
 

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Think about it this way, with your subs in the trunk just in a normal box they already have to fight their way through the back seat partition, cover, rear seat and MLV (mass loaded vinyl) that covers the rear seat back. I think a piece of carpet should be the least of your concerns.
I just posted my setup.. I have a 12" poking through my ski-pass. I can notice a HUGE difference from when it was just sitting in my trunk away from the pass. Is that to say that I wouldn't give up that added bass for full use of my spare? Nope, I mean I do have use of my spare currently with my small box, but I would love to run a rear strut bar... can't have both!
 

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I beg to differ on that point as well. Check out this picture. The top and bottom holes are ports. but that middle hole/pipe pass trough isn't. Anything is possible if you think of a creative solution ;)

http://i17.photobucket.com/albums/b75/ItalynStylion/Finished builds/StrutTowerBox001.jpg
Still... makes it harder to get your spare out, and theres no chance a big 12" would fit in that. Plus I just meant it more as you cant have it all... (well until you make this!)

Haven't even thought about this from a performance aspect...

Lower COG since the subs low, able to run rear strut bar... Do eet...
 
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