I Purchased this hifonics amplifier and had my whole system professionally installed at a local shop. I Received a call later that evening that the amplifier was toast right out of the box. I even visited the shop a little later, and sure enough the amplifier was not outputting power. Either way i learned my lesson and replaced the hifonics product with a 500 watt kicker amp that was inspected at the factory and passed all quality control tests. Chalk this up to either bad luck or a sketchy product. Seemed like quite a few people liked this product though and had good luck with it.