Alot of people dont understand 10's wont pick up low bass SLAPPP freqs... You have to have some good ass 12's with a good amp backup to pick low freqs up & if its not proper they wont even pick it up trust me put a bass cd/ whole bass album in your slab thats how you adjust your shit, without music at alll just bass low's, mids, & high bass frequency or 15's to pick up super low freq.. but its all about how u adjust it.. I have heard 12's that shit on 15's because their adjusted right & have more watts on each sub, but I also have heard two 15's that shit on 4-6 12's..