When to recap a pre-amp

[Fongolio]

I have a Carver C-1 pre-amp and a SAE Two PA-10 pre-amp in the mail. Both are 25 years or so old. My question is how does a person know when it's time to re-cap them? What will I hear or not hear? Which caps do you replace and what do you replace them with? To my ears the Carver still sounds great but at 25 plus years those caps must be nearing the end of their usable life. Thanks for any input.

Kelvin

[ben62670]

When it is bad enough to hear some crackling you have gone way past the rebuild time. I am recapping my GFA-565 mono blocks soon. Still sounds good, but I know it can be improved with new better caps. 20 years it is do for a rebuild.
Ben

[george daniel]

Guys,,I cannot say enough about the Clarity MR's that I just put in my pre.
They are that good.

[FTGV]

My question is how does a person know when it's time to re-cap them?

The presence of 120hz hum is one indicator of main filter cap issues and apparent lack of bass can happen with aged electrolytics used for input/ output coupling and feedback duties.

Which caps do you replace and what do you replace them with?

Look at replacing any electrolytics especially the main filter caps and those in the signal path.Replace power supply caps with electrolytics of the same value.Replace any electolytic coupling caps with good film caps if there is room enough on the PC board to do so.