Appreciate everyone's input. I believe I am converging on a solution.
Stay tuned for further developments...........
Amazon Music High Definition and Ultra High Definition Equipment Requirements
My goal is to use my late-model iPhone to stream music from Amazon HD/Ultra-HD through some sort of DAC and then on to my stereo (old McIntosh with Bozak speakers). I see that the upper transmission rate specified by Amazon is 24 bit/192 kHz. Am I correct in assuming that a DAC such as, for example, the Schiit Modi+ , will allow me to accomplish this goal? For reference, here is. link to specs on this DAC: