Back when I had my TS-W2000SPL on the Viper 1200 when I opened the trunk and stood right infront of the sub it sounded normal and I could feel the bass.W hen my Viper blew and I to use a 250W Cadence amp and I opened the trunk and stood infront of the sub it would just making a strange muffled underwater type sound and I didn't feel any bass but on the inside it sounded OK. The sub didn't look like it was moving right. Even though I don't have that system anymore I was just wondering why that happened. That second amp didn't even have a gain or subsonic filter.