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Amperex "Bugle Boy" tube compatibility

I need to replace a vacuum tube in a pre-amp section of the integrated amplifier as the previous tube Beijing 6N11 went bad. The Amperex "Bugle Boy" ECC83/12AX7 tube has the same pin layout as Beijing 6N11 tube. According to description on Amazon the Beijing 6N11 may be used instead of ECC88, E88CC, 6922, 6DJ8, 6922 and 7308. Would it be okay to use Amperex "Bugle Boy" as a substitute to Beijing 6N11 tube?

esputnix

Showing 4 responses by lewm

lewm
12,459 posts
 
Wouldn't Amperex "Bugle Boy" ECC88s, if BB ECC88s were ever actually made by Amperex, be a premium value in tube world?  If so, you can bet someone somewhere has made some fakes of it.  I think there are even fake Telefunkens with the diamond engraved in the glass envelope on the base.  To distinguish that TFK fake from real, you have to know whether the diamond is embossed or engraved (in other words, sitting ON the glass surface or grooved into the glass surface).
lewm
12,459 posts
 
Dover, Now I should be responsible if someone doesn’t read the entirety of one of my posts? Especially as in this case I have already stated in no uncertain terms that the proposal is a no-go, for two other compelling reasons? I think I have always been courteous to you, even when on the odd occasion I have disagreed with advice you’ve given. I am actually rather shocked at your vitriol, which seems uncalled for, if not also ridiculous. By the way, the fact is that you CAN run a 12AX7 off a 6.3V filament supply, in case that’s what you are so enraged about.  When running the filaments off a 12V supply, the filament supply attaches to pins 4 and 5, which lights up both halves of the tube with the respective filaments in series.  Pin 9 is left open.  If you are using a 6.3V supply, you use pins 4 and 9 for one half and pins 5 and 9 for the other half of the dual triode.  This is a unique feature of the 12AU, T, Y, and X7 dual triodes.
lewm
12,459 posts
 
Actually you can run a 12AX7 with a 6V filament supply. In this case it would only require some re-wiring of the tube socket. But that’s the least of the reasons why not to do it.
lewm
12,459 posts
 
No.
12AX7/ECC83 has very different pin out from any of those tubes you have named that are said to be compatible with the 6N11. Things equal to the same thing are equal to each other. Things not equal to the same thing won’t work. Furthermore, the electrical characteristics of a 12AX7 are also very very different from any of the tubes you listed. In other words, you would not want to replace a 6N11 with a 12AX7, even if you could.
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