MC452 and a bit brightness

Hi, i had a MC302, and now i replace with MC452.
This have more detail than MC302. but i listen a bit brightness. He have 50 hours aprox break-in.
can smooth more after sixty hours ?
You may wish to talk directly to McIntosh. They will give you a straight answer.
The MC452 definitely communicates more detail than its predecessors and doesn't have the dead top end of earlier McIntosh autoformer-output amps. My experience with modern McIntosh autoformer amps is that it will take a few hundred hours of use for it to fully settle into fleshed out tonal balance. Early, it's biased to transient detail and light on letting the rest of the note bloom and decay. You'll be hearing improvement over 300 - 500 hours.

Further, the resolution that amp is capable of demands reconsideration of what comes before it.