Phil Allison wrote:
"Brian Gaff"
I think one has to be careful if buying the Chinese copies of valves
around at the current time, as quality control is almost non existent,
though some Russian ones are made a lot better I'm told.



** Why refer to them as " Chinese copies of valves " ??

My info is that the Chinese purchased valve making equipment ( including
dies and materials) from Europe when factories there closed in the 1980s and
transported it to China.

This is so they could easily start making popular audio valves like EL34s,
6L6s and 12AX7s - for which there were no equivalent Chinese types in
production at the time.



.... Phil




That assumes that all that is required to make good tubes is the
equipment. Whether or not the Chinese have the necessary know how as
well is moot.

Cheers

Ian