I have found a way to do this. Makes a world of difference. Have a 3.2 setup, which is conducive for my listening setup. For now.
Focal Sopras front L and R are connected to my Luxman 509x. Center sopra is connected to a Peachtree amp500. My streaming source is a Aurender A10 which is connected to the Luxman. REL 212SE x 2 are connected to the Luxman via high level inputs. LFE inputs from the REL are connected to my Marantz SR 7010 subwoofer outputs. My Marantz then acts as my preamp only. And needless to say, the LCR channels are connected to the pre-outs of the Marantz and the respective inputs on the Luxman and Peachtree. When I wanna watch TV/HT, I use the Luxman’s HT bypass switch. It’s called ‘seperate’ on the Luxman remote. Other manufacturers call it HT bypass, Direct Input, Mains in, etc. And switch it off so I can stream music from the Aurender through the Luxman for 2-channel only.
It would essentially be the same setup for a 5.1, but with more speakers and separate amps to drive them, all connected to the AV receiver or Pre-pro for HT use, and simply switching the HT bypass switch back to off for only 2-channel listening. This way, as someone mentioned, I’m not dependent on my Marantz preamp for my 2-channel listening, but rather on my Aurender’s...If you want to expand your soundstage by using subwoofers for both HT and 2-channel listening, options are limited. For me the RELs make perfect sense here, because of separate high-level and LFE inputs. Best of both worlds I suppose.. Sorry if my description is a bit confusing..