Aging of capacitors within crossover networks

"'passive'-component values in crossovers is highly overrated IMO"

Disagree. Small changes here can make huge changes in sound.

"caps, resistors, and inductors in crossovers are of a + or -10% tolerance from the beginning, and some are + or - 20%"

You don't think the person building the crossover tests them all? Come on.

"Also understand that it takes doubling or having of a component's value to change its effect by one octave."

that depends on the crossover topology, not true in all cases, AFAIk.

"Replace with higher-quality parts for better sound? "

Maybe, maybe not. doing so presumes you know more about the parts/sound/speaker/crossover than the designer, which I find is not often the case. Parts usually were chosen for a reason, and that is not always price.

"Axon 'propylenes without any bypasses" - which is not a bad thing. Axon (aka Solen) is basically about the best film cap that can be had in larger values (say, over 10uf.) in the .1-1uf range there are lots of choices however.

Regarding caps degrading - its' mostly electrolytic types that have this problem, and then usually in stuff that runs higher voltage than speakers. (e.g. amps, power supply bypass, etc.) IN that case, replacing elytics is a good idea. Even better is getting rid of them entirely and replacing with oil or film caps.

-Ed

The premise that

more expensive = better sound

or

more botiquey = better sound

is what I find to be a fallacy. Sometimes it's true, sometimes its' not. Unless you try every reasonable value of every type cap in a particular application, there can be no conclusions drawn one way or another. IMHO, the manufacturer is a lot more likely to have done experiments like that than any end user is likely to do.

most expensive parts do not equal necessarily better sound. Case in point re: caps - I'd take a vintage (read: cheap-ass $2 or so) paper-in-oil cap over ANYTHING made by Blackgate, for values where it's appropriate (mostly power supply stuff). there couldnt' be a greater difference in price vs. hype vs. quality of sound. The cheap ugly oil cap sounds and performs way better than the overrated Elytic.

-Ed