I have a Concept CC2400? Rated at 600 at 4 ohms 2400 at 1 ohm. Last week on 2 ,very old, 15" Diamond CM3's I hit a all time best of 149.6 db on the Term Lab!!!! I've run this amp at 1/2 ohm for the last year,competing with it for the last 2, daily, I don't jam every minute but I do get on it. You have to keep your voltage up, or the amp will heat. I've owned it since I bought it off E-Bay 2 1/2 years ago, repaired $250.00, but ran it at 1 ohm until I found out it likes 1/2.