IMO, pure 2 channel systems are obsolete when compared to a modern AVR up-mixer. I've found that using the newer Dolby Surround Up-mixer to an Atmos speaker system (or any 5.1 \/7.1 system) to be vastly "night and day" superior to the standard "pure direct" stereo mode for 2 channel music sources. I believe this is due to many things including the general sound processing, speaker volume frequency equalization, bass management, subwoofers, room correction, and multi-channel upmix processing by Dolby or DTX that many modern AVR surround sound processor \/ recievers have built-in by default. Modern integrated amps and stereo recievers have no such sound processing power as in modern AVRs, putting them IMHO at a huge disadvantage (especially the speaker equalization and room correction). What ever happened to stereo sound equalizers anyway? I know they were really popular in the 80's. I'm I taking crazy pills, or do others on this forum confirm my reasoning? Thanks in advance.