I play also at moderate levels. I live in a house in a row (direct neighbours on both sides, no not know the right English word for it)
In my previous house i played louder because i could, but i do not have the idea i am missing something now.

A 6 Ohm speaker can draw more out of the amp than a 8 Ohm i think, but the power section of the end amp is limiting somwhere.

I have once measured with an radio Shack SPL meter and reached peaks of 100 dB i think (was a while ago in my previous house)

I cannot comment on the heating up. My 558 units are installed in a 19" rack on top of each other with like 5 cm (2") room voor ventilation between top side and shelf of the above device. My 19" rack doors are open front and rear while playing.

The units get hand warm

Jaco

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