My current 7.1 HT system consists of Polk RTi4 front. surround, back. and Polk Csi3 center speakers. I want to upgrade to LSi9 fronts, LSi7 surround and backs eventually by starting with a LSiC center. I have a Denon 3805 receiver w/120 wattsx7, and a Velodyne 3750 sub. All speakers are currently set to small with a crossover of 100Hz to the sub. Due to financial constraints (wife), I will probably be buying the remaining LSi speakers over a 12mo. period. I have the following concerns with this upgrade: 1) Would the Denon drive the LSi 4ohm speakers without damage along with the RTi's ? 2)Will the Denon's auto setup/eq program compensate for the volume differences? 3) Will there be an audible difference in voice matching? I know that larger amps would be better for the new speakers so I will plan on yet another upgrade. In the meantime I will listen to HT and music at moderate levels and check for overheating and distortion. Thanks.