I've ran a 10'' BL and 10'' DC lv4xl in the same box and the lv4xl is waaaaay louder on the low end than the BL, not even a comparison. I really liked how my BL sounded but I think the XL sounds just as good and can handle more power. I know there's a huge difference between 4-15s and just one 10'' but I hope that helps.
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