Two sets of stereo speakers + Tyros

[bpsafran]

I would be grateful if anyone had experience connecting a Tyros (in my case, a Tyros5) to two sets of stereo powered speakers.  I have a soundbar+subwoofer as well as a small stereo PA amp and speakers.  The soundbar is in front of the keyboard and the PA speakers in the back of the room.  Is it useful to connect them both - one as line out and the other as aux out?   Should I consider connecting one as line out and the other as sub1 and sub2 with specific channels on those sub outs?

Thanks