i have 2 10 in digital designs subs rated 450 rms...i have a memphis 500watt D class amp pushing them with gain turned up a lil over half way...ive only had the speakers for about 3 months,everything was fine until a few days ago.one blew and the other blew tonight.i have a premier deck that displays volts in real time....im always around 13volts at any given time.i didnt really have it up that loud when they blew...i had 2 10 in MTX that were less of quality than these i have now...i beat those speakers for 4 yrs and nuttin like this ever happened.