How do you know when tubes are done?

Thanx Veridian! My first ST-70 cost $79 in kit form. Can't remember what the built price was. Those M-125 amps look very interesting maybe for a small system up stairs. Let's see...Rogers LS3-5As. TD 124 with an SME on it. A PAS 3X. Just like old times:)

roberjerman you are showing your age! Heathkit? Us Dynaco guys use to sneer at the Heathkit guys but you had to be braver to do a Heathkit because you had to build the boards, Dynacos you just had to do the point to point wiring. Bravo! I wish manufacturers would offer kit versions of their stuff again. Anyway, I always keep a spare set of tubes on hand. If you think something is off you can always swap to make sure. Actually, I always keep a spare set of everything around which I think is a neurosis. I would have a spare wife but I'd get shot. Think of what would happen if I got Atma-sphere MA-3s. I would be buried in tubes then get shot.
Steamboy with less gain in both channels I would suspect a power supply problem. Check your voltages. Great that you built your own stuff!