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Old Sylvania black-plate bent getter 12au7s

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Using an ECC82/12au7 in place of an ECC83/12ax7 will make a big difference, sure.
A lot less gain of course. Different harmonic signature.
To what other types/brands did you compare?

Ps
You will probable get more response in the MI amps section.
 
have some old GE and Sylvania grey-plate 12AX7s, GEs are clearly better/more detailed, have a few of the GE 12AY7s they are/got weak though, thought they were fairly detailed as well.....and a few of the new/newer stuff like JJ ecc83s and Russian 12ax7s and Chinese 12ax7Bs, nothing really special there at all just more of the excessive gainy/bland/fizz/fuzz city.... and the 12AU7s I have amperex world logo's, those sylvania's and and few blackburn's, a few rca clear tops etc,

I don't know I just think/thought those Bp sylvania's really stood out as far as being transparent/detailed actual noticeable difference etc
 
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