Subwoofer with center channel

I don't think sub frequencies are sent to the center channel.

@carlsbad2 I was wondering about that. 

Sub frequencies can go to the center channel. It depends on how you set your sizing of your speakers in your home theater.  For example, I have my center channel and surrounds set to M which then only delivers over 80 Hz. My 2 main channels that are connected to REL subs are set to XXL delivering significantly lower bass. 

@woots I went back through the menu on my Onkyo.  It does have a crossover frequency adjustment for the center channel.  I have it set at 60Hz, so I assume everything below that is going to the subwoofer?  My Sonus Faber center channel speaker is rated at 65-24,000Hz.  

I guess I could set it to full range and use my NHT subwoofer.  Set the crossover frequency on the NHT so only signals above 50Hz to 60 Hz go to the center channel speaker.  Doesn't seem like that would help much versus letting the low frequencies go to my main subs. 

You do not want a sub on the center channel. Male voices will be sent to the sub, and it will smear, distort, be hard to understand. Usually you cross the center over 100hz. The HT receiver will divert all bass to the subs, no need to add an extra one if you are using LFE. That is why it's there in the first place. 

Any HT/multi ch recording will have 80% of the sound going to the center channel. Unless you have your HT setup perfectly music will sound like it's all coming from the center. Truth is you have your center setup incorrectly. It should play at the same volume/db as the rest of the speakers.