does 2 channel mean no amp?

It says "40W Total Power". That means it includes an amplifier.

You're very welcome.

How do you think they work?

Of course...why ask that?

how do you think speakers are driven...magic?

There is a wide variety of devices sold as soundbars.
Some have HDMI connections and internal amps.
Some have line-level analog connections and internal amps.
Some have speaker connections and no internal amps -- so you need a separate receiver for them.
And some have absurdly high prices for little content.

In other words, you have to shop carefully to get the type you need.

Note that soundbars with larger speakers usually will provide better sound than the ones with tiny speakers, but they'll also tend to cost more. Some have external "subwoofers" to improve the sound. I put the word "subwoofer" in quotes because they usually are nothing of the kind. They're frequently just separate woofers used to fill in the upper bass that the tiny speakers in the soundbar itself can't provide. Subwoofers typically have speakers larger than 8" in diameter plus their own builtin amplifier.

woosh....right over your head....thanks for trying though

lol

2 channel means 2 speakers. As opposed to 5.1 which is 5 speakers, .1 = one subwoofer.

Some sound bars have amplifiers and some don't; most do, but you can't assume it.

Read the detailed specs.

I read the spec on the lg soundbar that you asked about. If good sound is what you're after, what does 10% THD mean when it comes to sound quality?

It means that dialog will probably sound like someone speaking with tin foil over their mouth. LOL

It says the output is 20w x 2 at 10% THD, so I'm guessing that 5 to 8 watts is all these are good for when it comes to clean audio.