• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Alternative to EF184

6AU6= UK-EF94-Mullard --B7G base (UK designation ) --that's all supposing you can get a genuine Mullard tube ?


PS- US "9 pin mini has a UK designation of B9A --its called the -
Pro Electron type nomenclature system for receiving and amplifying valves .
 
Lower gain to EF184 is E83F (mu=40)
Great tube, and one of the tube with least noise.

Here is E83F triode curves:
 

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Returning to the schematic I saw it contains two drawing errors. The polarity of voltage sources V2 and V4 are reversed providing the fase splitter and the power tubes a positive instead of a negative voltage. This would make the powertubes blush a little.
 
Think you will see the voltage is shown as -70 etc so is correct. And before someone tells me it should not be a BC548 its a MPSA42 in the real unit. I needed a lot of gain in the LPT as the GNF is taken back to this stage rather than the first.