Up for sale is my earthquake maker Adire Audio Tempest 15" Subwoofer that I custom made in black ash. It is 49" wide, 20" tall with rubber feet, and 18" deep. The enclosure is a net 218L (7.7cf) enclosure and has variable tuning via its dual 3" flared ports. In maximum output mode (both ports open) it is tuned to 17.5hz(best for HT), in max extention mode (1 port blocked) it is tuned to 12.5hz(best for organ type music), it can also run sealed with both ports blocked. It has a Q of ~.577 with a group delay of ~20 @ 20hz with both ports open, and a group delay of ~12 @ 20hz with 1 port plugged. The cabinet has two internal braces with five 5" holes in each brace to decouple standing waves, and is stuffed with 4 lbs of acoustic polyfill to mimic a larger enclosure. This sub has response down to 15hz in room, plays flat down to 18hz, and has an anechoic response of 110db+ spl @ 20hz.. It has a front grille that I made as well. It is powered via a 380watts RMS @ 4 ohm Rythmik Audio plate amplifier with variable damping, subsonic, phase, crossover, and gain filters. It took me 4 days to build this and i breathed in a lot of dust, and put in a lot of time but it was well worth it. The sub is made to stand on its side as the bottom has no laminate, just rubber feet. If you can live with its size it is going to beat anything you can buy for the price that I am asking. $200 local pickup only. I live in Orange County, Lake Forest Area near Irvine.