duesentrieb":98ea6 said:Let your ears decide, at 475/480V there is a safe area, where just your ears decide:
Keep in mind that in the pic its for single tubes, while the recommendations are for PAIRS. Also in the pic you see tubes with a max. plate dissipation of 25 AND 30 Watts. 6L6GCs have 30 Watts.
30*550/475 = 35 mA (single tube), so up to 70mA for a pair.
If you prefer 60mA or 70mA for a pair - let your ears decide.