Thanks for your reply. I believe that Dolby Volume disables Audyssey's own dynamic volume program, but does not disable the Audyssey EQ program. Page 53 of the manual states, "When 'Dolby Volume' is set to 'On', the 'Dynamic EQ' and 'Dynamic Volume' settings of all input selectors are switched to 'Off'" (it's important to note that "Dynamic EQ" is not the same as the main Audyssey EQ settings, but rather is a setting that "solves the problem of deteriorating sound quality as volume is decreased by taking into account human perception and room acoustics. [Dynamic EQ] does so by selecting the correct frequency response and surround volume levels moment-by-moment so that the content sounds the way it was created at any volume level — not just at reference level"). Also, when I have Dolby Volume engaged, the front display of the receiver still indicates that "Audyssey" is engaged.
My concern was that the volume level I choose on the Onkyo may affect the operation of the Dolby Volume program. Dolby Volume, in effect, appears to perform the function of both Audyssey's "Dynamic Volume" and Audyssey's "Dynamic EQ":
"Dolby Volume automatically adjusts the difference in volume levels which can occur between different contents or source components, freeing the user from having to make volume adjustments. Also, by adjusting the frequency balance according to the playback volume, it recreates the original source audio."
Since Dolby Volume appears to be making "frequency balance" adjustments that vary based on the output volume level in order to preserve the perceptual frequency balance for the listener, my concern was that setting a volume level on the Onkyo, only to adjust the actual volume I hear using the volume control on my McIntosh, may affect the operation of Dolby Volume.
(and I'm just curious if the volume level setting would have any other consequences in a pre-amp/power-amp type of setup).