You definately should get a RadioShack SPL meter (get the analog one, not the digital) and calibrate your system. You should be listening to movies near the "00" on the main volume to get the levels the film was originally mixed at, and your CD playback levels should be near this also.

As I answered you in another thread, connect up that Dynaco tube amp. It will sound a lot better with the Cornwalls than any solid state amp will. It also might be a good idea to check that all the drivers in your speakers are functioning to original factory specs. The effects of time, air pollution (smoking in particular), moisture and salt air can deteriorate speaker cones. You might give Klipsch a call and ask them about this.