Yea. I found on Yamaha's website, that if all speakers are set Small, and bass out to sub, that all LFE/BASS for those channels in directed to the sub. Now if all speakers are set small and LFE/BASS out is set to BOTH, then all again is directed to sub. This is right off the site. I agree the manual was not clear. The reason this is come up, is when ( both ) is selected, and mains are set a (small ) the Subs come to life. I have a feeling That when set to small, the bass management is not redirecting main channel bass to sub. Unless mains Channel is set small, and bass out is set to both . again according to their website, if Bass out is set to both, And mains are set to (small ) LFE/bass is directed to the sub. Thanks for responding PENG