Thought I'd add to this after having my surround speakers installed and the system tweaked.Late to the party here but I'll put in my two cents. What you buy isn't nearly as important as how you set it up. I have a second hand Klipsch Reference set that a friend of mine (professional audio engineer) positioned and tuned. The before and after is incredible. An expensive but poorly setup system won't sound nearly as good as a budget system that's been setup properly.
The improvement was mind blowing. Just finding the optimal settings on the AVR made a huge difference.
We also did back to back comparisons of the Firestick, Apple TV, apps on the TV, and video streaming services. My biggest takeaway was that compressed music and video sucks. I ditched the TV apps and ended up with an Apple TV, signed up for Tidal after being a lifetime Pandora subscriber, and put a Kaleidescape Strato V on my short list.
Movie Players and Media Servers for Your Home - Kaleidescape
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