I removed all the inner panels from the trunk this weekend then unscrewed the sub amp so I could Dynamat the whole trunk and found that the little stock amp says it is 40 watts per channel. It also has a gain control on it (volume control). I turned up the gain and left it in when we went out to eat Saturday night. Let me tell you that it puts out a lot of base when its turned up. I opened the trunk and turned it down before we started home because it was booming so much. I dont know if having the trunk completely covered with Dynomat affected it or not. So if you can't afford a amp and sub woofer upgrade yet just turn it up the stock amp and it will pump some sounds out.