UPDATE:
I decided to work on my system to see if I could improve the sound of my Sierras in my new HT space.
Well after reading some online documentation about Audyssey, I decided to calibrate my system using Audyssey and my Denon receiver.
Oops!!! Audyssey revealed that my center channel was wired out of phase.
I don't know how I missed that! Audyssey found it almost immediately. I'm blaming the mistake on old age, and all the excitement and planing involved in building the new home we moved into 4 months ago.
After the calibration, and phase fix the Sierras came to life. The Sierras now sound as good as I remember them in my smaller room in our previous home. I didn't totally rely on Audyssey for shaping the sound, though. I made a few changes to suit my personal listening tastes.
I'm extremely pleased with the results. To think, I was about to sell the Sierras and buy 340s.