The highly acclaimed HE15 driver is available at a steal of a preorder price of $395 from http://www.stryke.com/ until the 14th of June. This driver usually retails at $1000. It has been designed to give unrivalled performance in a small enclosure (22" cube) with two 18" passive radiators (ports are not a viable option). Go to http://www.stryke.com/ for the full details including the enclosure plans. This thread from the AVS Forum- http://www.avsforum.com/ubb/Forum3/HTML/003352.htm is a detailed account of the construction of this sub and various things related to this project. I emailed John E. Janowitz (http://www.stryke.com/ owner) for a shipping price for the two passive radiators and the HE15- Two 18" PRs- $228 HE15 $395 Shipping $105 (this is obviously to my address). So thats $728. Using the Universal Currency Converter that equates to £526. Add 25% for the pleasure of importing these beasts and we get £658. This sub needs a 1000 Watts of power. http://www.bkelec.com/ have the answer with the MF1000. 1000 Watts into 2 Ohms, perfect for the job, £261. So it's about £919 for the hardware, This leaves the cost for the MDF enclosure, finishing and other bits and bats and you'll have a world beating sub. In his reply to me John E. Janowitz said he will answer personally in this thread any questions anybody may have. This is an opportunity not to be missed. I've ordered mine.