Can you install a 10" sub behind driver w/o a box?
 

I was looking at the space behind the driver seat, and this guy who does installations told me that we could dynamat the front metal plate and then fill up the space with polyfill. My question is- can this be done like that or do I need an enclosure for the sub? I'll be keeping the stock head unit and replace the speakers, so as to mantain the stock look without eating up space, and the amp would go behind passenger. Feedback on this? Thank you.

You would need to get a free-air sub. I thought about doing the same thing, but most people I talked to said it would not sound good.

So, what did you do with that 8" sub?

Back mount sub
 

I tried that myself, I was planning using that bracket and keep everything as simple as possible. I tried a free air sub as well as a non free air with as much as fill to enclose that space, it does not worth the effort in my opinion, unless you are planning to build a custom box that will fit right there and the sub will fire to the front... The sound was horrible, it reminded me the sound (off the sub) of that Bose systems... I then put the sub in a box, and put it behind the seat in the stocl location, firing upwords... still if the box would be in the trunk you would end up with a much better sound field and fill. I did not want to have the sub there so I had to compromise on sound quality. If you do however build a custom box with sub firing to the front, you might be able to go 12"... but that will require a very tricky box, I guess. just my opinion... Happy listening.

All right. The idea of the sub in that bracket is out. Now the two options I'm contemplating right now are an Infinity Basslink behind driver or a Bazooka SAS nitro held somewhere in the trunk. I don't think I'll go for a custom made box, but I'll keep on looking for options. Another thing- should I change the HU or not?

If you search hard, you can still find a QUALITY Free Air Sub from JL Audio. It's the 10IB4. It's a nice sub that will run at 100 watts RMS. I installed it and spent $7.00 for the Sub cover from my dealer. I'll admit that it doesn't supply the ground shaking, vibrate every screw loose from you car kind of bass, but with that sub, and a set of Infinity Kappa components up front running off the amp at 50 watts RMS for the components, 100 watts for the sub, and a set of Infinity KAppa 63.5 3 ways for fill (running off the 18watt RMS Clarion Pro head unit) the system is AWESOME compared to stock.

Be warned, this sub was discontinued, but the authorized dealers should still be able to get some. I paid $99.00 for mine (but I am good friends with the store manager)

so am i to understand that to put a sub in the stock enclosure in my enthusiast, I can only use a free air sub, and no other type?

I purchased a alpine 10 inch type r woofer to be placed behind the driver's seat. I'm going to build a box but still use the metal stock woofer plate as the face of the box. Do you guys think having a box of two diferent materials (metal and 1/2 mdf wood) would affect the sound terribly?

i would not recomend using the metal face plate, it will not give it a good seal, it would be better to make the whole box. i have attached pic of my install. it sounds so much better with the box,
i got too much rattle and distortion with out it.
You wont be disappointed!

here is a pic of the box installed

Taya, you put a free-air sub back there and it sounded horrible? What do you mean by horrible? Was it simply not loud enough or did you notice virbations or garbled sounds? i dont have the patience or desire to build a box, so I just want to put a free-air sub back there, screw it in and enjoy my music.

Please check your PMs!

Def don’t use the metal face plate; ill post some pics of my install later today when I borrow a friend’s digi camera.

I made a custom metal face plate to seal up any air holes, surrounded it by mdf but used the bottom of the pre existing sub box using foam to seal and I am getting some nasty vibrations at high volumes. The existing metal box is just not sturdy enough to support a strong sub.

Thanks for the input, I'll make a wooden box too:) YOur box looks so well made. Did you use 1/2" or 3/4" mdf?

the box was made with 1/2" Compressed Wood. Very heavy but solid box

Infinite Baffle anyone??? Hehe

350Z-RED,

Nice Job on the box..

Using the stock location is exactly the route I want to take. I had been contemplating the free air route. No doubt your install was quite a bit more difficult, but I bet it really pays off in sound quality.

Would love to have a measurement schematic on the box. Not that I am lazy :D , but because I am sure you had quite a bit of trial and error to get it just right.

Going dipole (free air) in a car would be very difficult. I don't think it would work to well. I'd only want to deal with 1 wave and not 2 especially when the other is out of phase with the other. Monopole (in a box) will get you more SPL and will probably be easier to set up.

the box was the exact measurements of the plastic sleeve in the glove box

If you built it with the exact same measurements, how did you get the box inside the compartment? The first few inches are sloped, then it levels out. How did you get the box through this kink if it had identical measurments?