Please note that this was the very last stock item of the previous production batch and became unavailable for several months after my order, August 2013. Valves, (like fruit or nuts) do vary one from another ! I have been an amp tech since the early 1970's as well as musician. I've seen dozens, if not a few hundred. This could easily be a one off rogue production item. Bugera amps get some really excellent customer ratings - and rightly so ! Often though, the users state that they have had to replace valves in them. I thought it was time for me to do an independent assessment and now I have. There was nothing too special about the sound, but the internal physical construction of the valve is atrocious and I wouldn't want to risk this in an amp I'm using, as a little vibration could easily cause a short circuit which would be likely to then cause serious damage to the amp's internal circuitry. I have now donated the valve to thenationalvalvemuseum.org / r-type.org and it is shown with detailed photographs of the internal structure. The fourth, last (magnified) image shows a very wonky anode (the grey box), which should be perfectly aligned with the internal cathode and grid. The ECC83A's now in stock may have come from a different supplier, or even a different country, so may be quite ok. I suppose this doesn't really help you decide either way.
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