[R-390] Orange Drop vs ceramic disc

[MillerKE6F at aol.com]

Good point on the self healing and I believe I did mention that as a  
significant consideration.  But an anecdotal observation dating for over 55  
years spent in the communications industry and specifically maintenance related, 
 the number of capacitor failures specifically related to types would 
suggest  that aside from electrolytic types, most of the tubular capacitors I've 
seen go  to the dark side were as follows.  Listed from most frequent to 
less  frequent:
 
Paper Oil caps of the "Plastic cased Bumble Bee" style
Paper oil caps mostly get leaky both physically and mechanically
Vitamin Q
Plastic cased Oil paper caps
small cased mica caps (WWII)
Silver Mica caps (WWII)
Big Oil Paper High Voltage Caps
Most leaded ceramic types
Metal Film mylar
Metal mylar
Epoxy sealed silver mica
Polystyrene ( when not exposed to chemicals and solvents)
Polyprop
 
 
This list is based on failure or leakage and not as a function of  
performance such as 
ESR, Q, D, etc.  Nor does it address subliminal or subjective  analysis  as 
is often attributed to "Audiophile" preferences, preferences  which seem to 
put much to much emphasis on the alleged superiority of "Bumble  Bee" caps 
and other units in that category that will leak and short without much  
provocation after many years of noble service.
 
Bob, KE6F