I understand the OP's dilemma, indeed it is a bone of contention with me.
I don't listen at loud levels. Think that our hearing when we age is different, & of course our mindset too.
Ime the set up that gives all the detail, with a suggestion of bass, isnt necessarily the one best at even slightly higher listening levels.
Being realistic and knowing ones room helps, but accepting a happy medium that isn't perfect is perhaps the key.
I wanted a little more weight & drive. Achieved this with a class A amp but the trade off is having to listen a little louder. Have enjoyed the vibrancy of horns as my hearing became rolled off. If I pull my ears forward I get a taste of how I used to listen
My best amp for low volumes is class A/B and I seem to have a finer/larger range to use with the volume control on the Pre. What to do ?
Find what suits your own ears. Smile. Listen to the music..not the system.
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@JANDL100.. I would love the option of a loudness button.