Tube Amp accident

My first miserable experience happened the day before yesterday. An indispensable Vacuum Tube Diode was destroyed by Inrush current when the toggle switch was turned on, apparently destructive spark was observed, how come! Parallel connected capacitor for the prevention might have been killed because of age?
Hatred rush current is caused by the big volume capacitor connected on power supply circuitry at the beginning phase. Some reasonable circuitry for the prevention exists utilizing semiconductors and it is possible for me to set it in my tube amp, but I would not like to do that in a classic circuitry at all. Basically, I'm afraid of some change of sound character by adding unnecessary parts.
The Rectifier formed with 4 solid semiconductors changes sound quality completely.
Though a replacement Russian Tube Diode is put on it for emergency, I'll look for some suitable one in the Web site.
As I do not have the way to countermeasure except in my experience, a study on this kind of problem begins now.
JBL 20 cm full range speakers sound best in my listening room for as long as 30 years.