naamanf

Just find a friend with a router and a circle jig, should be able to make rings all day.

I think going the IB route is probably the easiest route that will satisfy most people with improved bass. For those that are worried about loosing a bit of shelve clearance I am sure a more compact sub that is suitable for IB can be found.

As for powerhandling of the sub, it isn't going to change per say with IB use. Most powerhandling is based on the thermal limits of the voice coil which isn't going to change no matter how you mount the sub. The only you thing you have to worry about is the sub exceeding it's maximum excursion and the voice coil leaving the pole gap.

td80

I had considered this, but it would take a pretty tall spacer. I think there was about 1.5" inches of gap between the mounting ring of the sub and the rear deck. Even with this gap and a spacer, there is plenty of room for the sub to fit below the factory speaker grill so it definitely would still all fit there. So far I've settled with a very narrow 0.8 cubic foot box that I have temporarily mounted off to one side as a test. I was REALLY trying to avoid this but I might settle due to laziness at this point.

koobah

Here's another option that might work, however I'm not sure if Pioneer has released this for US market:

A subwoofer that fits inside the rim of a spare wheel.

If you are looking for an amplified subwoofer but would rather not give up your boot space, consider the TS-WX610A. This all-in-one solution for in-car bass is designed to fit right into your 14 inch spare wheel – just place your subwoofer in your wheel.

Easily installed, it will provide for a powerful and dynamic sound thanks to 2.10 Dual Voice Coil speakers and a 200W MOSFET amplifier. The Speaker Level Input allows for a fast connection to factory-fitted desks.
Less distortion and stronger sound

Internally, the TS-WX610A is cleverly structured. Because of the position of the two speakers within the enclosure, you’ll get less distorted and stronger, more refined sound, while using less power than other active subwoofer designs.

With a die-cast aluminium frame construction and aluminium top panel this subs design is strong and durable.

Nutdotnet

I'm thinking the ED SQ10 might be a good option, however, with it being 4ohm, it *may* cause some issue.

http://www.edesignaudio.com/product_...roducts_id=106

Edit - For those worried about clearance issues, have you thought about going w/ an 8" sub like this?

http://www.crutchfield.com/s_130SW84...1D.html?tp=111

koobah

Both of these are 4 ohm, so yes they might cause the amp to overload. I'm still very curious as to how much power the stock amp is feeding to the sub. Searched everywhere, but could not find a number.

helix139

When mine gets here I'll get a multimeter and figure this out. It would be simple enough to find amperage and voltage with a multimeter and a CD of test tones with the volume cranked to max, then just multiply the two for wattage.

koobah

Please do.

Nutdotnet

Exactly. However, so far I think the only sub that people have tried that is essentially a "direct-fit" is the JL that the OP used.

It would be nice to find a sub that states it can be used in IB form, 8ohm, and doesn't need to use an MDF ring or similar. I've been looking but haven't been very successful.

sworksone

I just completed the JL Audio sub upgrade this morning with only a few minor changes. I unwound the sub wires from the grouped wires for the right rear speaker and trunk light a bit so that I could fit them through a hole closer to the sub so that I wouldn't have to splice in additional speaker wire. This also allowed me to turn the sub a bit so that the terminals were facing directly forward. The sound quality is greatly improved. The B&O system always seemed to be missing something, and now it sounds like I expected it to when I first picked the car up. Thanks to the OP for the excellent DIY that made for an easy installation.

Brandonb

Glad to hear it worked out for you, and the guide was helpful! I found the sound gets even a little better after a week of break in.

Good point on separating the wiring harness. I'll edit the guide to suggest that.