Tube Amp's tubes

[keysersoze808]

yeah, i rem fixed biased needs to be rebaised, cuz last time my bassman was fixed biased.

Tubes to be matched, so that run equally hot

this is why this subject always confiusing... fix bias actually got adjustable trimpot to adjust negative supply to grid. fix bias amp actually need to rebias if change tubes , diffrent tubes draw dif. amount of current. the chatode bias actually dont have to rebais..(champ, valbee) just swap in new tubes..and crank it up :twisted: