01-09-2016, 09:15 PM
Hi Dave.
Yes I would agree that at low levels the amp is still in class A. The problem with an even higher value of cathode resistor is its dissipation, increased heat from the resistors will offset to some extent the reduced heat in the bottles.
The other problem is of course the effective output will drop, to compensate the HT needs to rise then of course we are talking about different mains transformers or going to silicon rectifiers and in a way going back to the mods that were in the amp before to its detriment.
The customer has had the amp back for nearly a week now, so far no calls to say there is any problem and when demonstrated on collection he had a big smile on his face............. that was good enough for me
Yes I would agree that at low levels the amp is still in class A. The problem with an even higher value of cathode resistor is its dissipation, increased heat from the resistors will offset to some extent the reduced heat in the bottles.
The other problem is of course the effective output will drop, to compensate the HT needs to rise then of course we are talking about different mains transformers or going to silicon rectifiers and in a way going back to the mods that were in the amp before to its detriment.
The customer has had the amp back for nearly a week now, so far no calls to say there is any problem and when demonstrated on collection he had a big smile on his face............. that was good enough for me
