Ive run some listening tests for both digital and analog inputs of Yamaha's Pure Direct function and Ive observed the following results. Please note that the AVR was set to straight mode which sets the AVR to output into its channels, what it gets at the input. There is no muxing of any kind in Straight mode. Straight mode also maintains all the settings from the results of running YPAO.
Analog In
Pure Direct works as described shutting down all DSP including bass management.
HDMI In
Here's where it gets a little quirky Running an ATMOS source or a 5.1 source, Pure Direct maintains outputting to all channels as I expected. What is quirky is that it only shuts off PEQ filters but bass management is still maintained as I was receiving bass from my subs in Pure Direct mode. This is not mentioned in any of their manuals up to and including the RX-A3060. The way pure direct is described in their manuals, it would shut off all DSP and to me bass management is a DSP function. My thoughts are Pure Direct with digital inputs is nothing more than a Blue LED indicator that by passes PEQ only.
Ive also had email discussions with Yamaha support reps and they maintain that all inputs whether analog or digital get converted to digital. Yeah, I scratched my head on the digital inputs being re converted to digital . Looking at Gene's preliminary reports, its very clear to me that analog in and even digital inputs with Pure Direct engaged has a much greater bandwidth then with Pure Direct disengaged. Could Yamaha be doing a double conversion on digital inputs? I hope Gene can chime in.