Didn't read all the posts so hopefully I'm not repeating someone. If possible, I would add another dedicated line just for the amp. While you are at it, I would have a separate line for your analog equipment and a separate line for your digital equipment as well. Then I would decide about the power conditioner. That being said, I have always found power conditioners to help in my room, but the separate lines will make a huge difference on their own.
Good listening
Good listening