Cable for JBL MK 2, External card, Polk psw10

[swtscp]

Hello,

 

So recently i bought some JBL 305P MkII and i also bought a  Polk audio psw10 and i got my behringer u control sound card with its rca input and output

 

i also bought some xlr (M) to rca cable 

 

what else do i need? and am i wrong buying the xlr to rca?

 

Thanks for your time

 

first pic is the polk and second is the jbl

 

 

 

 

 

 

 

 

[swtscp]

i bought some rca to 1/4 and everything works like a charm