P Paul Joppa Moderator Jul 6, 2010 #2 It needs more bias, nearly 5 volts unless the plate current is increased. The 12AY7 should work directly, and is a highly regarded audio tube. I haven't tried it yet.
It needs more bias, nearly 5 volts unless the plate current is increased. The 12AY7 should work directly, and is a highly regarded audio tube. I haven't tried it yet.
