It is a lot cheaper to increase the signal strength by 3-5 db. Almost never does anyone run their system anywhere near the max output. Channeling more signal to the center channel is a good way to get an idea of what a separate amp would sound like and avoid having to get a separate amp. The OPs speakers are 90 db efficient at 1 wpc. Even at 50 wpc the SPL would approach 105db which is way louder than most can listen at for very long.
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Music system
Model 990/7500/Magnepan 1.6 QRs/Technics SL1200 MK2/Aperion S-12 Subwoofer/OWA3/Sony NS75H DVD
APC H15 Power Conditioner

TV System
Large Advent Loudspeakers/ Polk center/Monoprice surrounds/Panasonic Viera 42 inch/Onkyo HT-RC260/Sony BDP S590/Directv


Home Theater System
Onkyo PR-SC886/Outlaw 7125 Klipsch RF-82 L/R,RC-62 center, RB-35 SR/SL, BENQ HT1075, Outlaw LFM1-EX/OPPO BDP-83/Directv
Harmony ONE
Blue Jeans and Monoprice interconnects
APC H15 Power Conditioner