Depends on a lot of things. How big is your room? Does it open to other areas in your house? What type of music material do you listen to? How big is your powered sub? Do you like to listen to stuff loud? Etc, etc. But remember one thing, power and dB output is logrithmic. As you increase dB levels you need more and more power to achieve an increases of 1 dB. It's not a linear relationship.