I have TWO 12" MTX Jackhammer subs with each having 500w peak power, frequency response of 34 - 150hz, RMS power handling of 250w, and they are 4 ohm. When I bought them i could only afford to get a chea amp which is a alpine mono amp which is pushing around 300 watts. Should i get a new amp that is more powerful? and if i should, what amp should i get or what specifications should i look for (wattage)?