The original PV10 used 12ax7, 12at7 and 5751, tubes with much higher gain than the 12au7.
http://www.conradjohnson.com/It_just_sounds_right/a-PV10.html
You may want to cal CJ with the serial number and ask about the correct tubes for your unit.
Good luck
http://www.conradjohnson.com/It_just_sounds_right/a-PV10.html
You may want to cal CJ with the serial number and ask about the correct tubes for your unit.
Good luck