Definitely check your speaker cable polarity on both speakers and the amp end. I know it's "basic" suggestion but when swapping speakers, it's something that can easily happen.
I know because I nearly drove myself insane trying to fix an imaging problem only to discover that I had misconnected one speaker out of phase. Yes, I felt like an idiot. . .but got over it quickly when I realized I hadn't made a major purchase error and how good everything sounded properly connected.
I know because I nearly drove myself insane trying to fix an imaging problem only to discover that I had misconnected one speaker out of phase. Yes, I felt like an idiot. . .but got over it quickly when I realized I hadn't made a major purchase error and how good everything sounded properly connected.