I have a 1200 watt phoenix digital 2 channel amp i don't know what rms it is and two pioneer 15's thier 300 rms and 600 peak thier dual voice coil and 2x4 ohm when i hook them up amp goes into secured mode when i bridge it they sound like crap they don't hit solid and they kinda rattle when i hook up just one it drills very hard and very smooth i hooked up each of them so it's not the speakers i think i need a bigger amp any suggestions