Latik is correct in that Roon and the other music players each have unique sound qualities. I have multiple choices available to me at present, Stylus which is Euphony's proprietary player, HQPLayer and Roon, each has unique settings and sound quality.
Some contend Roon sound inferior to various proprietary music players, that may be true for their own individual setup. Roon's great interface may negatively affect SQ in some cases in that it's complex interface may require greater use of available processor capacity, which may result in more noise generated by streamer. Proprietary music player apps may have advantage in that manufacturer has optimized player for the specific hardware used in streamer, I presume this is what Aurender Conductor users are hearing.
I'd suggest Roon SQ is highly variable since it can interface with wide variety of streamers. Because of this judgments of SQ highly subjective. With my present streamer Roon core is using less than 1% of processor resources, Roon SQ wonderful, at least on par with Stylus and HQPlayer although still have multiple configuration to experiment with.