I would contact Oppo but it looks to me like you could run balanced for the amp and then RCA for the sub or add those RCA adaptors which allow you to double up the lines.
The cylindrical SVS is passive, the box one that I use with the 3.7s is active. The passive really makes the most sense as the amplifier isn't being rattled into garbage but they're not in vogue much these days.
The 20.7s weigh around 100 pounds each. You won't be carrying the box into the house by yourself, that much I know.
They have slippery oval bases which make them real easy to slide around, though, along with little handles on the back for fine tuning the positioning if you're so inclined.
The good news is you won't need a subwoofer with 20.7s!