Replacing Capacitors, I Don’t Wanna!

Is the amp beginning to hum, make any other noises, or otherwise sound like it is going bad?  Does your amp run hot all of the time?  If it is not acting up, and it is not an amp that subjects its internal parts to high heat levels, I would not worry that much about the state of the capacitors.  You could have someone just take a look under the cover for bulging/leaking caps, resistors that look a little burnt, etc.  If your tech looking under the hood can do in-circuit tests of capacitors (equivalent series resistance (ESR)), he might be able to spot one going bad without big hassles and high labor cost. 

A preventative replacement of all caps seems extreme to me.

That's real BS.  

Usually, the electrolytic capacitor in audio amplifiers would last many years. The new ones are very reliable.

I used the LCR meter to check the ESR, dissipation factor, and capacitance to confirm the condition of the Capacitors. Without testing them with instrument, I won't replace them without any reason.

Replacing the capacitors with different type/kind, it maybe cause distortion/problems.

If it ain't break, don't fix it.

Johnny

@larryi @kmtang ;  Everything is working as it should, obviously no need to concern myself with replacing capacitors at this stage. To be fair, I think my speaker tech has the tendency to overthink things. So what you’ve both shared is pragmatic and sound advice. 

I looked at a picture under the hood and I see those blue caps are the Vishay BC 135 series capacitors. Their lifespan is 250,000 hours at a 40C ambient. That's over 28 years if you do the maths. If the temperature inside the case is lower, say 30C, then the lifespan is 630,000 hours. So hopefully by then your great-great-grandchildren will be handy with a soldering iron.