Whatever I Did, It Worked.

I'm really enjoying my new JA Pulsars. Still messing around with the room treatments. So, tonight, I placed a GIK 244 Bass Trap behind each speaker and next to the corner traps. I don't know why, but the articulation of instruments, particularly piano, became super clear; before, it sounded just a tad rolled off. My room is 11x9x8 and is well treated. What's the science behind having achieved this result?