The 12AX7 was the most common member of what eventually became a large family of twin-triode vacuum tubes, manufactured all over the world, all sharing the same pinout (EIA 9A). Most used heaters which could be optionally wired in series (12.6V) or parallel (6.3V), with respective current requirements of 150 mA or 300 mA. Other tubes, which in some cases could be interchangeable, include the 12AT7, 12AU7, 12AV7, and the low-voltage 12U7, plus many 4-digit EIA series dual triodes. They span a wide range of voltage gain, ruggedness, and transconductance.
I am guessing since they are interchangeable according to the above information. I would think you will not do any harm to the amp if placed in the wrong socket. I would still wait until someone with more knowledge can guide you in the right direction.
I am guessing since they are interchangeable according to the above information. I would think you will not do any harm to the amp if placed in the wrong socket. I would still wait until someone with more knowledge can guide you in the right direction.