Also, if you have a purpose built electrical system that outputs more than 13.8 volts, buyer beware on the standard Stetsom amplifiers. I had an alternator that was built to idle at 14.5 volts, and my V1k5h was always going into protect in the cooler weather. Stetsom's customer support was so nice, they told me that the amplifier was built to run on electrical systems with 13.8 volts even though their documentation stated otherwise. Power Tension 9 to 15 volts, my @ss!
EDIT: Another gripe about Stetsom... Their cooling fans are LOUD. As in loud enough to hear over BFG KDW2 tires and a Borla Stinger Exhaust on a 4.6L V8 motor with the amplifier in the trunk loud!