My bad as I was a little sparse with info as I was looking to see how to move forward without losing an already excellent AVR that does not deserve being dumped to keep up with newer tech.
I use as inputs HDMI Coaxial and optical.....
HDMI does the pass thru and the Marantz handless the 7.1 sound and has always sounded excellent.
The Coaxial is from the TV as it is a unit that does not have ARC but is a 65" at 120HZ with ULED screen 4K so visuals are fine.
The optical I have running from an older model OPPO DVD player that I still use for my music CD's
The Marantz itself is set to Auto so the sound signals are switching correctly and displayed properly on the Marantz LED screen
Right now I am being patient as I am sure that some smart cookie will develop a gadget that can assist with DTS-X in the future.
The Dolby Atmos may sound cool but when people need to upgrade Speakers and their Amps then I do not see it as a viable option for those that have already spent a lot of money on Quality components.
DTS-X I think have more possibilities and also sounds awesome. I listened to some test samples and video at an exhibit a while ago in Shanghai and was impressed.
I am of the opinion that at some point someone will develop a box to decode the signals and allow the addition of extra speakers and amp.
Tech is moving so fast these days and as the system is entirely digital I see no reason why a box with 1 HDMI in cannot split that signal to 2 HDMI outs allowing for the extra spatial sounds to be sent to another source for amplification......
But I might just be dreaming