I'm thinking of purchasing one of these receivers as a gift for my dad. He has some infiniti speakers now, but will probably upgrade to some polk audio speakers. I've also seen some suggestions for the Yamaha 2400...Didn't know where that stood with regards to these receivers. Any advice would be greatly appreciated.
Considering both speaker brands I would go with the Onkyo. It is a better match sonically with both Infinity and Polk as it's a more warm sounding unit while the Yamaha's can be a bit bright. Both have similar power output and rather mediocre 5 channel power but that might not be a problem. I have always liked the Onkyo sound and have owned all the brands mentioned here and for me the Onkyo is the way to go. Yamaha would be fine for say, Paradigm or PSB but not such a good choice for Polk.