Unfortunately I have seen the practice of adding a single ecc83 to a transistor amplifier and fitting a string of big wirewound resistors from the 60v rail so that it lights up. A collection of passives are grouped around the valve to make it look good, but there are no volts on any of the electrodes. Removing the valve stops the smell of burning from the pcb under the resistors but has no other effect on the operation of the amplifier.
This amplifier is in current production by a well known and respected? manufacturer of guitar amplifiers but I can't remember who until I see another one. When I'm sure who it is I will shout their name.