Cool, a pair of dc level 4 10s will eat up just about his whole budget. And a 300 watt amp... To the OP if your trying to get LOUD you simply need a bigger budget. If you want to improve for short money, at least make the most of what you have, get a more powerful amp and if the L5 doesn't do it for you then you already have more power to work with try a different sub or subs.