MM2124, MM2154 or MM124

putting them "facing up" between the 6x9's in the back deck is called a "free air" installation.

this is where the sub uses the whole trunk like its "box" -- sorta.

anyway -- you cannot run any polk sub free air.

the only sub i know of that you can run free air is one pioneer model from a year or two ago.

it actually responds more like a woofer than a sub-woofer.

normal subwoofer frequency response is like 20 to say 120 hertz -- we normally cross them over at 80 to 100 so its more like 20 or 30 to 80.

now a "free air" sub will have a response more like 45 or 50 and up... and 45 to 80 is pretty **** honestly. it'll be bassy but not bassy enough to make u really happy i do not think

the only alternative is to mount the sub in the back deck LIKE it was free air, but then build a box that bolts up under the back deck, and hangs from the deck... this way the sub is IN the back deck between the two 6x9's but is actually in its own box. THAT is a killer setup and something i've wanted to do with my girlfriend's car and my old man's cadillac for a LOOOONNNGG time, but i haven't because its a lot of work -- it requires that you know that the hole you're cutting isn't going to decreases lateral stability of the car (some cars use that back deck as a lateral stabilizer and u can fk up structural integrity of hte vehicle) -- and you've gotta work your **** off to make sure it doesn't rattle.... long story short, it's not a one day isntall... it's a one day install with like a couple of days / weeks of getting all the damn bugs out.

you'd be much happier just putting sub(s) in the trunk and if you require more bass in the cabin just cut a six inch round hole in the back deck between the 6x9's so the bass from the sub in the trunk can "flow" through it -- you can put a speaker grille over the hole to make it look good.... this is what i did in the cadillac since hte car is friggin heavy gauge 1970's steel.... i put a 6x9 grille over the hole with two 8" subs firing right up into that hole beneath the deck -- worked out splendidly.

yeh my cousin has a pair of those pioneers youre talking about. 12" 500W max... but i think they sound pretty nice.... clear and loud.

I know a carpenter so im sure i can get something done about that hanging box. I could make the required box size (.88 cubic feet?) and then under that i could make a stand for it and stuff some foam in and around it so it would be stable and wont make any noise. Im going to have to take off the plastic piece covering the 6x9's because it vibrates.

And i think i busted one of my sony xplod speakers... the right one is giving off this wierd noise.

And do you know of any other good free air woofers? I think that would make my life easier.

JL makes a strictly freeair sub... don't know if you can find it nowadays, it's discontinued, but anyway, it's the IB4. Probably better quality than the Pioneer and you might be able to get some direct from JL pretty cheap since they are discontinued.
JL drivers are better quality than Pioneer drivers. Although I am curious about the new Pioneer competition sub.

if you're putting it in the back deck --- the 2104 -- you're gonna have a hell of a time getting a friggin 12 or 15 into a deck.

if you're putting it in the trunk, the 12 or 15... in which case... i dunno.... maybe the 15...prolly get louder for you.

... sounddomain has the mm104 in the glass polk box (the nice lookin ones) for 159 -- less than half of its $399 circuit city price.

that might be an option, even though it's only a ten, hell u could rip it out of hte damn box and put it in whatever box u wanted... for 159 i mean hell -- and then sell the box to somebody for 50 bucks.

ya this is no knock against you -- you're just the customer -- sony has lost pride in its workmanship and design -- old sony mobile ES head units were pretty darned nice, and old sony amps were respectable to "high mid grade stuff"... nice amps... but now they build horse shizzle and expect us to pay big bucks for it.

i would suggest selling u're sony 6x9's on ebay and trying out either of the following...

1- polk momo 6x9
2- polk db junior 6x9
3- polk ex III 6x9
4- polk DX 6x9
5- alpine type R 6x9
6- Kenwood excelon 6x9
7- Pioneer's upper end 6x9

with any luck you can pick up a set new on ebay for like 100 - 125 and sell your old ones for like 50 - 70... that's not too bad at all.

the pentagon sub is WORTHLESS, it may sound better than another sony sub but it won't hold it's own against any halfway decent sub from another brand. i'd almost be willing to buy lanzar or pyle before i bought one of those subs. hell even look at it from a simple physics standpoint. the only sub design that can increase surface area with out changing the diameter (top to bottom) is the square, which you lose lots of controll when you get into that. the pentagon has neither the controll or the surface area of a circular sub, that's why no intelligent company has done it. Sony is all flash and styling, that's why they went with the worthless cone shape, so they could sell it to stupid kids who's friends all bought the sony decks cause they like the xplod logo and think the sub looks cool. If any of my friends ever wasted their money on that piece of **** in a box i'd beat the crap outa them.