with thr new l7 they fixed alot of the porblems tha the old one had, like the fact the the spider would rip after alot of use and the new ons handel more power but they dont tell you that. when i was at kicker traning they told me the it will handel 1000 watts all day and the old would max at 100 watts but i still wouldnt put that much power on it, other changes have been made like an extended bump stop, a new vent that is in the solo-x 18 this is for cooling the subs motor structure