Some years ago I purchased this amp and it had issues , It was consigned into a wardrobe in the bedroom
Some years later I found it again and decided to get it sorted , at first I though it may be V fet issues , however after speaking to Mike Powell he said If a V fet had blown ( No longer available ) you would get no sound out of the affected channel , I packed it up and sent it to Bolton in Lancashire for a rebuild and testing , Some time later Mike contacted me saying its all done and ready to come back home
All Caps renewed even the 4 massive ones , had to wait 2 months for these to be made , Did I say they are massive
Mike has had it on test and has given it a clean bill of health , Cant wait to get it back , I asked Mike to do something with the pony binding posts that had at some time been fitted , they are now proper
This is a link to the VK web site showing the power amp
http://www.thevintageknob.org/sony-TA-N7B.html