folks, Alan is right!! cone excursion is a very, very important factor in subwoofer design. For 12"", DIY'ers prefer the Shiva, Dayton DVC and the NHT have been a long classic... Now the cream of the crop are the BluePrint Drivers... The Dayton Titanic MKII Drivers(10"and 12") also have very good specifications. http://www.partsexpress.com/pe/showdetl.cfm?&User_ID=6934716&St=4413&St2=88059427&St3=71946153&DS_ID=3&Product_ID=15171&DID=7 is the address of the kit I own. There you will find even a review of Wes Helms of the subwoofer. You will also find all the complete specification of the subwoofer. the subwoofer is a 1"4.25" cube so is small... and the cost is only $349... now we're talking!

What really matters is getting the sweet spot!