Can I use a 12AX7 with CT 6.3V?

[Captn Dave]

Remember, the purpose of the CT on heater windings is to raise the potential of the entire winding in lieu of a humbucking pot. Nothing more really.

 

[DF96]

Not necessarily raise the potential, depends what you attach the CT to. CT helps if hum coming from capacitive pickup from heater wiring, as it balances the voltage. Humdinger better because it allows for adjustment. Humdinger worse because it allows for misadjustment!

 

[v4lve lover]

damm this ain't rocket science positive to both 4&5 on 12ax7 ant earth on the center tap . ( he drew that correctly ) for 6n2p operation you dont need to remove the earth from pin 9 but you will have to convert either pin 4 or 5 to earth course the fill is pin 4&5 .

i rest mine ..

 

[quikie22]

V4lve... I have to agree with DF96.... the schemes drawn by the OP will provide wrong voltages across the various filaments. Maybe you mistook the voltages involved.. it's stated as a 3.15V-0-3.15V transformer by the OP. (IF the voltage of the transformer was 6.3V-0-6.3V, then the diagrams should work)

Anyway, the tubes would appear to work with such low voltages, but such cold heaters would mean the cathodes would be working below their rated emissions and may even cause the tubes to fail prematurely...