I have a 15" Kicker L7(1000w RMS) and a Hifonics Brutus(1200w RMS), can I blow this speaker?

As long s the amp isn't clipping, you'll be fine. Clipping causes distortion, distortion causes the voice coil to overheat and eventually fail. Just set the gain properly and you're set. Here's a link to a good method for setting gain controls. http://www.blazerforum.com/m_66322/tm.htm This way is pretty accurate and will ensure that the amplified input is matched to the head unit's output. When you read the tutorial, you'll find that you need to figure out a target voltage output. The math is really pretty simple. The formula is: square root of(voltage X resistance). Example: 1000 watts X 2 ohms = 2000. The square root of 2000 is 44.72. This is the target voltage. It's a little confusing at first. But< once you do it, it's a little more understandable.