What mA do you expect with a 6P15P-EB?

How do these meters work? Does the input tube affect the output?

Mine are same as trip.

The mA reading on a UFO2 with 6N1P-EB tubes range from 20~40, the majority landing around 24 mA.  It depends on the tubes themselves.  Interestingly, with this tube, there does not seem to be a real difference in sound or power output between one that reads 20 vs. one that reads 30, so the more important reading is that of similarity.  Whatever one tube reads, ideally the other should also read.  If they are different beyond 5 mA there is usually a channel imbalance.

Steve

Hi Alex,

The meters are measuring current, which does not change much over the life of the tube.  Transconductance is the measure of lifespan and sadly the meters do not give any real indication of transconductance.

The best way to tell if your tubes need replaced, is to replace them with new and see if you can hear a difference.  If the tube is past its prime, you will hear it because it will sound diminished.

Steve