issues with a GZ34 and open circuit anode resistors.

[bikerhifinut]

that's about it Richard.

I reckon what i will do as a test/temp fix is to introduce a 4.7uF 630V polyprop LCR that I have a pair of as first cap before the big choke. that will keep the voltage up and also be ok for use with say a 5U4G (miles cheaper than GZ34). The choke and following Electrolytics will be fine for smoothing and reservoir duties. I also will be using proper wirewounds, John C told me last year that those coffin jobs are not really very reliable and i think a better resistor will tolerate a momentary surge much better as I think the problems lie with the initial surge as the first cap charges up.
The present transformer is over specced and has good regulation if a bit noisy. I was looking at making a cover with ventilation holes for the transformers from some sort of wood or metal with damping material stuck on the inside surfaces that might prevent the buzz from being audible at the armchair.

I do have a massive toroid but my feeling now is to make a stereo chassis with it and try and get the best out of these monos for now.

I'm wary of commercial mains transformers now as these are the second batch (different makers) that have been noisy beyond reasonable expectation. It is possible to make silent EI transformers as my leaks and the WD amps testify.

A.