I have a home system that I use for both music and HT. It is composed of an Onkyo RZ-1100, two Polk Lsim 705 for mains, one Polk 706C for center, 6 Polk S15 for surrounds, and a HSU V15H-mk2.
I think that the Onkyo is roughly able to drive these speakers but the 705 are known to be not very efficient and I a looking for a dedicated power amplifier to drive the front 3 channels (while listening to music or HT). I am trying to get some opinions about going for a 3 channel Emotiva XPA-300 or the Outlaw 5000x. The Outlaw is quite a bit cheaper, yet seems to get good reviews and the additional channels could later on be use for two extra surround or by-amp the 705s.
Any opinion about this or a suggestion for another amplifier?
I might actually just be paranoid and my RZ-1100 might just be good enough, even with headroom while listening at 75dB at my listening position (8-9 feet away from 705s). The Peak SPL calculator indicates that this amp would produce 109dB, which is more than enough for say 75dB+ 20dB headroom. The Onkyo power ratings of this amp are sort of fishy however and the Polk 705 get quite a bit lower than 8 ohm... so would it really be safer to use an external amp, even for moderate use, and, maybe more importantly, would I notice any differences while listening to a movie at ~75dB?