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.
I just got my hands on some 6AK4 submini triodes, and they look like they might be a reasonable choice for a compact preamp, as the curves are nice and linear. Has anyone worked with these little fellers before?