Having done the same, with a Yammy AVR, in the past . . . I would suggest one change to previous advice;
set your "power amp" AVR volume to 0dB (i.e. full power) and let the "pre-amp" AVR control the volume just as it does normally for its own internal amps.
Worked like a champ for me.
A Harmony remote made "power amp" AVR On/Off and Pure Direct selection easy as pie.
Cheers,
XEagleDriver
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