Finally got my PWK Designs enclosure built for my 18" xcon. The design is a series tuned 6th order and it's in an 07 Avalanche powered on an hifonics hfi 2k. With this set-up the amp is working great the last box had the sub begging for more power on the lows so I'm guessing my box rise with this design is much less. This is after about 30 min of play time and the subs suspension continues to break into this new box getting louder by the minute. I will try to make another video next week if I have my truck, the trannsmission has been having a lot of issues and is going back in Monday for the 5th time.