To re-cap or not to re-cap? That is the question


I've got some very fine 1980s vintage equipment I love and don't want to replace. Recently, I was able to locate a company that repaired the drivers in my ailing speakers; I'd auditioned half a dozen excellent speakers in my home in anticipation of needing to replace my Teslas, and none pleased me as much. The amplifier has been serviced by a local audio engineer I trust--but he describes himself as a "recovering audiophile," and may not be the right person to ask what I want to ask here. Namely: should I have the capacitors in the amp, and perhaps also in the speakers' crossovers, replaced? Is there any other service protocol I should consider?

On the principle "don't fix it if it ain't broke," I'm inclined to leave well enough alone. I don't notice any audible deficit. But perhaps the system could sound even better?

Your sage advice will be appreciated.
128x128snilf
I will bid for amplifier. Just to check what the fuss about tubes really is. I have no experience with Chi-Fi and this would be my chance.
Since I don’t want his Moabs, would you like all the Chinese communist drivers that they’re built with? 
You should replace any 40 year old electrolytic caps or else move on to newer stuff.  Period.  As has been mentioned, parts quality in 2020 is much better than what was available 40 years ago, and electrolytic caps don't last anywhere near 40 years. 

I will restrict my comments to speakers, since I don't have any actual experience working on electronics.  I can tell you that I am currently rebuilding a pair of ADS 1290/2 speaker crossovers.  I've been very slow and deliberate about this, replacing one crossover component at a time and evaluating the change after burn in one one crossover while leaving the other crossover stock.  I also had the tweeters and mids reconditioned.

 As has been mentioned, you can go overboard and change the character of a speaker, which you don't want to do.  If you wanted something that sounded different, you would just buy something modern.  

At this point, I've replaced about replaced about 2/3 of the caps and resistors in one crossover using good but not great parts.  I've left the inductors alone so far.  The improvement is not subtle.  The crossover with the old parts is quite veiled compared to the partially modified crossover.   But the character of the speaker has not really changed.  It is quite musical and is seemingly incapable of anything approaching fatiguing. 

Having gone this far, I am building a new crossover board that is point to point wired and eliminates the extraneous (as far as I am concerned) switches. 

This has been a great learning experience for me and  very rewarding.  I encourage you to proceed.  Just don't be in a big hurry and make sure you have your circuits understood before you start.  
An election that was won in a landslide is being stolen in a so far relatively bloodless coup.
I don't believe they've stolen the election with the insurrection carry on. Even Mitch said so.

Make sure to allow the recapped amp to burn in before judgement.