Class A input buffer

I like the sound of this buffer In my Nad C272 amp but, the question is, is it really clever to have 3 caps in the signalpath, first there is a 0,22uf, the output a 100uf bypassed with 10nf (seems high) and then finally a 10uf before heading into the gainstage..

Anyone see any improvement that can be made with this design by Björn Erik Edvardsen?

Can the 100uf be deleted? Or what the pro’s say?

Also there is a aluminium box screening this off from rest off amp? Is it so sensitive part that you need it? I have now removed it due to the heat.

The 667/647 runs extremely hot now I can add (like cooking!) and heard from many repairguys that they often have to replace them.

Thanks for any help. I’m a beginner in this and like to learn more.


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