What budget does he have? Does he want discrete sub outputs or can he go with a splitter. Not many programs have any material for two separate subs so a splitter works pretty well usually. The polk need at least 150 watts but will benefit from the subs. Does he lean towards separates or a receiver? Blue tooth input can be had in some models. The Marantz 5005 could work well in a 5.1 setup especially if you bi-amp the mains with two channels each. The mains can use up to 300 watts so maybe a receiver won't cut it but the 5005 is on sale with free shipping.
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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