Critical Mass started out as a great company, and had very good build quality, innovation, customer service... But when they were bought out by this bunch of yahoos and the founder left, it went to crap.ok it is my impression that these critical mass ul-a2500 v2 amps are not truly 1ohm stable. i upgraded my alternator from a 150 to a 180amp. i upgraded the big 3 with 0 gauge and ran 0 gauge (replacing my 4 gauge) to the rear kinetik and to the amp per critical mass to fix the overheating issue. NO CHANGE. in one ohm with a steady 12.2 volt running to the amp it would over heat and go into protection within 20 seconds. the amp ran just as hot running at 2 ohm but never shut off. so you can buy them all day on ebay for around $600 but IMO they are worth maybe $200-250 for what you get out of them. the amp is poorly crafted. it looks like a $200.00 amp. this company is all hype, and their tech support is worthless. the box it ships in is a joke and the "manual" was literally 4 8x10 pages printed off on a black and white printer and stapled together. i also found that american bass makes an identical amp, the phantom ph4000md. google it... its the same chassis, the same side panels and connectors and very similar specs. this amp sells for $250-300.
stay away! dont believe the hype! buy what you know or can go somewhere and listen too. there is a reason why there is little to no info on this company or any of their amps anywhere on the internet.