Replacing capacitors in Dalquist DQ-10 Speakers


I am considering having the five capacitors replaced in each of my Dalquist DQ-10 speakers which I have owned since 1976. I did previously have the woofers re-coned many years ago.
It is hard to determine whether the age has had a significant reduction in frequency response as they still sound excellent although I would like to make sure they are working at the level of the manufacturers specifications. I have been told that replacing the caps may change the overall balance and quality of the sound that Dalquist had achieved but I would like to make sure I am getting the best sound that the speakers were designed to produce.
Can anyone advise me as to whether I should have the caps changed simply as a result of the age of the speakers and if so what brand of capacitors would be best?
Thanks,
Andy 
andyhifiman
If your capacitors are the original, yellow, metalized Mylar pieces; they don’t need replacement.      They’re not affected, by age.     Of course; there are numerous newer capacitors, that would offer a different presentation.            Whether such a change would be for, "better" or, "worse", would be a matter of your taste.      If you’re happy with your sound, leave them alone.
You might want to see here:

https://community.klipsch.com/index.php?/topic/124268-dahlquist-dq-10/

As for age, no, film caps don't break down.  As for quality... I'd replace the film caps and the resistors.

I'd also carefully replace the electrolytic. That one WILL age, but you have to measure the ESR to avoid causing impedance issues.
I appreciate your responses. 
These are the original capacitors so I think I will just sit tight at this time until I notice some diminished sound quality around a particular frequency range.
I would in fact replace that electrolytic though. You might find it’s better. To be safe, stick to another electrolytic, Belnic, same uF, equal or higher voltage.