I expect you will hear an improvement if you add the 7500. I had a Elite 43tx and added the ATI 2005 (virtually identical to the 7500) that I now use. There was a definite improvement. Adding the amp is a nice way to incrementally upgrade your system and an amp can be used with new pre/pros as technology changes. That sounds like where you are headed. I will say when I added the 990 the sound REALLY improved over the 43tx.