I hate to start yet another advice thread, but I think these req's are unique enough.

Budget: Not a concern.

Size: I want to put in two subs into cabinets that have openings for each sub of just 13.25" wide, 18.5" high and 19" deep. Yep, very small. The cabinet has about 10" more headroom inside above the opening, and a bit more to sides as well.

Room: About 7,500 cu ft. (OK, please stop laughing now at these reqs).

Use: Movies

Also, I do have a good 600w/ch 2 channel amp (into 2, 4, or 8 ohms) that I could use to power a pair of passive subs if that makes it any better.

And I'm not opposed to looking at a pair of custom subs if that's what it'll take.

Thanks.

You may want to consider a pair of Velodyne SC-10 Subwoofers (12 7/8" x 12 3/8" x 9 1/2"). Don't expect them to really shake your room, however. That's a pretty big room. At moderate volume they should do ok. Also, to get the best out of them, they should be used with their matching external amp, SC-1250, which has auto eq and is specifically dsigned for th subs in the SC series.

I hate to start yet another advice thread, but I think these req's are unique enough.

Budget: Not a concern.

Size: I want to put in two subs into cabinets that have openings for each sub of just 13.25" wide, 18.5" high and 19" deep. Yep, very small. The cabinet has about 10" more headroom inside above the opening, and a bit more to sides as well.

Room: About 7,500 cu ft. (OK, please stop laughing now at these reqs).

Use: Movies

Also, I do have a good 600w/ch 2 channel amp (into 2, 4, or 8 ohms) that I could use to power a pair of passive subs if that makes it any better.

And I'm not opposed to looking at a pair of custom subs if that's what it'll take.

Thanks.

Have you thought about installing a couple of custom Infinite Baffle subs? If you have room or rather the right set of circumstances they can be mounted either in the attic or into the floor. I know you can find a lot of information in the DIY forum about them.

Don't know what to tell you about the size restrictions trying to work a couple into a cabinet. You shouldn't have too much trouble finding some subs to fit...it's the output I'd be worried about.

2 small subs in a room of that size, it will be better than no sub but as the others have said, I wouldn't expect the same amount of shaking as is usually posted on these boards.

Best ones I can think of are the SVS SB12-plus

I've been living with the lack of shaking from two full range L/R towers with no subs. It worked for a while OK, but as I separately drove the woofers of those towers, I got to a point where I'm bottoming out those woofers fairly often. More and more movies have really strong and deep LFE, and at least one driver (of the four, two on each tower) bottoms out. So I'm now looking at seeing what dedicated subs can do.

Unfortunately, the theater is literally built in a concrete box, so no attic, or even significant wall cavity space is available for an infinite baffle.

Please keep the suggestions coming, I'll check into them. Thanks.

Two of these Sunfire's ought to put a dent into that big room.
http://sunfire.com/TrueSubwooferEQPR.htm

5400w max output between the pair!! Might do some damage to the wallet as well, but you said budget was not a concern!!

Two of these Sunfire's ought to put a dent into that big room.
http://sunfire.com/TrueSubwooferEQPR.htm

5400w max output between the pair!! Might do some damage to the wallet as well, but you said budget was not a concern!!

If price is no object he might as well get the top of the line Sunfire sub. It is only a 13" cube so it would fit and it goes down to 16Hz. A pair of those would give your room all the bass that you would ever need.

Thanks for the link to Sunfire. The True Subwoofer EQ line wouldn't work since it has woofers on both sides (I need to put it into an enclosure). But Sunfire makes the Signature 12, which has 1500W and impressive specs. Two of those looks like it might work.

And now I just ran across the JL Audio Fathom F110 which also fits in the space, and might also be a good choice.

I think I heard one of the little Sunfires once, and I didn't like it, although it was probably the first one out and heck I don't remember which dealer it was at. But anyways, talking out of my butt here, price no object with your limitations, based on reputation I bet I could live with the small JL. Two would be better. But the penny pincher in me says try one at first. Doubt (talking out of my butt again) there are many subs that small with the driver tech, and pedigree that JL has, but it does come at a price I guess. With that said you sure you couldn't squeeze a SVS PC13 Ultra in the corner some where, buy a big bushy tree to put in front of it no one will know, at least I won't tell anyone, if that helps :p.

Just a follow up to my original post. I went ahead and bought two Sunfire Solitaire 12 subs. They had no problem at all filling up the room with deep bass. When I calibrated my cross overs and EQ settings, I ended up with pleasing tight bass and a nice deep rumble in LFE movies scenes. I'm happy and impressed. Thanks for the links and pointers guys.

Well, now that you're squared away, it's time to show off the goods! IOW, where are the pics? :)