For my EP-400s, I am required to use their Speaker Level Inputs from my Tube Integrated Amp's Speaker Out Posts.

My long run of speaker wires run under baseboards to the back of each sub where they attach to the Speaker In Posts. It is there where I've joined the speaker wires that go to the sats. So at the Speaker In Posts, both sets of wires are attached there & cinched up securely with the subs' screw nut.

Works just fine...

TAM