The SVS PC-Ultra is $1399 each plus $99 shipping.
http://www.svsound.com/products-sub-cyl-pcultra_new.cfm 
I had both in the theater system being driven by the LFE channel, but after reconfiguring the main systems...
...to operate without both channels' four 12" woofers* (and running the bass/MR stack full-range on the bottom), one PC-Ultra is now running in the 2-channel music system with a LP-filter point of about 40Hz...and sounding gorgeous.
* which will soon be running, with 4 of its brothers, in an infinite-baffle super-SW system.