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Do you have surround sound? If so, how many channels? If not, why?
Yes. 6.1 channels. The reason for 6.1 is that after replacing my old 5.1 system with a 6.1 system, I was less than bowled over by the addition of the rear surround, and so now that I have a 7.1 channel receiver, I did not bother putting in a second rear surround speaker.
If I move, and if there is room for it, I will add the other speaker when I set things up again. I do own a speaker for the position, but it is so trivial to me that I have not bothered to install it.
Is surround sound something you want (if you don't have it) or something you couldn't live without (if you have it)?
It would be easy to live without it. A good 2.0 system is what I listen to most of the time. But I do like surround sound for movies, and like multichannel SACDs better than 2 channel sources, if one sits in the right location. But most music recordings are not multichannel, so most of the time, it is of no importance to me with music.
And when one listens to background music, it is unimportant as well.
Do you find much content coming from your surround speakers when watching movies?
I think quite a few people are confused about this issue.
I have some classical multichannel SACDs that sound great, but one does not notice the surrounds, unless one shuts them off, and then the loss of realism is quite noticeable. The surrounds, if properly used, can make a big difference, but without always drawing attention to themselves.
With movies, it is usually exactly right, with a sound seeming to come from behind only when appropriate. It would be bizarre for the dialog and other such sounds to be coming from the rear as much as from the front for most movies. If one is expecting that, one has very peculiar expectations.
If you do have surround sound, did you spring for high quality surrounds or did you go for cheaper ones?
If you went cheaper on the surrounds, have you ever heard a system with expensive surround speakers? If so what brand? Did you notice any differences positive or negative?
I have identical speakers in all positions, except the subwoofers. I will never go back to different speakers for different positions, because I don't want the sound quality to change when a sound moves from one channel to another.
The surrounds are less important than the front, but "less important" does not mean "not important."
At what level do you usually watch movies and what is the noise floor of your room?
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I have not measured these things. And how loud I listen depends sometimes on mood.