new S520/S525 owner here.
wonderful speakers with serious 2-channel equipment. with mid-range AV receivers, no. mid-range being something up to 2k USD.
I tried an Denon x4000, sounded like someone put a blanket over the speakers. next was a Marantz 7008, better but not the sound i was looking for.
bought a refurbished Onkyo 818 to "hold" me on movie night while i looked for something else that would do music well. it's the most musical of all of them.
someday when i...