Need help finding the right tube for this amplifier

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bigdrums

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I have this well made amplifier I think was made in asia somewhere and now have all but 1 tube for it. The tube in question is a 9 pin preamp or phase inverter with heaters being pins 4,5 & 9 in common like a 12ax7 except that the heater voltages are 1.5v per side/3v total. I think all the other pins are the same as a 12ax7, and need to know what tube might work in this situation. There are 2ea 6z4 rectifiers and I think the proper power tubes are el84's There are no markings on the unit to tell me the manufacturer
 

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I suppose it's possible this requires a line voltage of 230-240v looking at the pics of the p/s, but even then the filament voltages would not be right for
a 12ax7 I don't believe
 

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6AX7 or ECC86. If heater voltage center is already grounded at a different place, not 6AX7.
I always started tube amplifier repair with sketching the circuit, if no schematic available.
 

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6L6 and 807s with dreams about 813s.... well, that never happened

I agree with FvM, it looks like the big transformer is 240V for HT and 3.15 - 0 - 3.15 to give center tapped 6.3V for the heaters. Pins 4,5 & 9 are almost certainly not commoned, 4 and 5 will be the heaters and possibly 9 is ground. They may measure shorted but certainly wont be. Some circuit tracing is needed.

Brian.
 

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