I have an audio store in my house, literally, and I went through the same thing.
I ran dedicated lines not because I wanted to I had to old house. I then tried different brands of power conditioners till I found one that I really liked, long story short I won't listen to a system plugged into a wall the sound just sucks.
A good power conditioner is mandatory for good sound.
A Monster is crap and will muck up the sound.