passes the sound signal through to audio in of some kind of amp which then amplifies the sound to send to speakers. True, if running the signal through a stereo amp, you can only really get stereo results. Yes, if desired, that can be run to two sets of speakers which MAY give you a nicer sense of ambiance.
Don't confuse wattage when referring to speakers. What is more important is the resistance stated in ohms. A wattage number in relation to speakers is a marketing thing that only refers to how many watts MAXIMUM that a speaker can use (to produce maximum volume.) In any decent system, maximum volume output is above & beyond the pain threshold.
Your TV wattage is only a factor of how many watts it uses to produce the picture (because we're talking about passing the sound signal out because TV sound is usually rather feeble, relatively speaking, thus the use of an external amp & speakers.
As to the speakers used with the amp: basic speakers most often have nominal ohm rating of 8. It is usually some more expensive speakers that use highly sophisticated engineering & use maybe ohms like 4 or below which is known as a difficult load. The amp then will need to be somewhat more sophisticated than most.
You need not fear damage to the TV. Theoretically, a really low powered amp could damage the external speakers because it does not furnish enough power to adequately run the speakers. The opposite - with a very high powered amp, merely has a bunch of excess power capability which won't be al used.
This question will probably label me a Luddite, but I ask nonetheless and implore any assistance. I'm running an XBOX 360 and a PS3 via component cables to my Samsung LCD HDTV. This TV, like most made in the past seven years, has an audio-out option. Using monster brand audio cables, I'm routing the TV's sound signal into the audio-in jacks on the stereo/amplifier which, in turn, routes the signal to four different speakers. This is not a true surround sound system, rather more like a hodgepodge consisting of a philips basic two speaker stereo with two aux sony satellite speakers. That is probably superfluous info-I mention it only in the context that the amp and speakers are compatible wattage. I have no idea how much wattage my TV has, or if that even matters. My only concern is not for the speakers, rather for the TV. Could this set-up possibly damage my TV in any way? Any help would be greatly appreciated! Thanks in advance!

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