I have an Onkyo ht-s5400. I just purchased two tsi400's, a cs10, and a psw10. Now I was wondering can I install another psw10 if i wanted to? If so i am not sure if my onkyo has another rca connection for a second sub? If it does not how would I go about installing a second one? thx. Second question is I was checking my setup in the onkyo menu and noticed that my sub is set to 150 mhz or was it klz...one of the two. Someone told me to set it to 120? In the same menu someone told me to set the two tsi400's to small so the sub can do all the work. When I took them off large there was a part in the menu that said double bass was off...what does that mean? can i get better bass with them set to large and double bass on? thx.