A:Answer Hello I'm not exactly sure why you care so much about the watts specifically because in a sound bar system it is a closed system that is made to work out of the box as is. As opposed to building a system where you need to provide your own power source with amps in order to get the most out of it. Soundbars do have limitations and are imitators of true surround sound not duplicators.
That being said what I can tell you is all four components have their own power cable, meaning you do not share power with other devices. They are all wireless in the sense of not needing to be connected to the main unit to work but you will require power on the front and rear end of your setup if you intend to use the small speakers as rear speakers instead of up front speakers.
In terms of sound this system out of the box doesn't disappoint. Will it be as good as a real 11.1.4 system, no, but you won't really care. You can crank this thing pretty high without having distortion, your milage will vary depending on how you set up your channels.
I hope this helps a bit. If you want a really technical review though I recommend this one.
https://www.rtings.com/soundbar/reviews/samsung/hw-q990c#test_2643
