Is a powered subwoofer necessary if using a subwoofer?
The description says that the power output is 39W total power output (8W x 2; 23W subwoofer) which implies to me that it is sending 23W to a subwoofer and if you have a passive subwoofer the 23 watts will drive the subwoofer. Understanding a powered subwoofer would have more power I have a passive subwoofer from a Cambridge SoundWorks 2.1 speaker system that is going unused since my old TV which would drive an external 5.1 system with the TV's amplifiers is no more that I could use (at least for now) without having to spend more money for another.
I would prefer the powered subwoofer. To me, it has has more sound and drop to it. If u are into bass, it is great. You just have to make sure that it is adjusted correctly so it doesn't over power your sound system.