How long should amps go for?

[gadawg]

I think your amps are just getting broken in good!

George

[PHC1]

Capacitors slowly degrade over time and there is even a formula out there to calculate the expected lifespan of electrolytics called the Arrhenius' Law of Chemical Activity. Other than a hard failure, a capacitor is considered as failed when it drifts 20-25% from its value. The 10-15 year life span is considered the norm as far as I know but the amp or preamp may go on working indefinitely with the caps that have drifted far from the specs. How that effects the operation is difficult to predict but I guess when Diana Krall starts sounding like a toad in a pond, it’s time to recap. So it’s not unusual for 30-40 year old gear to still operate but those capacitors will not be anywhere near their specs.

Heat/ambient temperatures are the number one determining factor of the life span of the caps. Keep your amps running cool and the lifespan will be greater. Simply put, the law says that life of a capacitor doubles for every 10 degree Celsius decrease in temperature (within limits). Same goes for speakers.

[vegaracer1]

Originally Posted by PHC1

Capacitors slowly degrade over time and there is even a formula out there to calculate the expected lifespan of electrolytics called the Arrhenius' Law of Chemical Activity. Other than a hard failure, a capacitor is considered as failed when it drifts 20-25% from its value. The 10-15 year life span is considered the norm as far as I know but the amp or preamp may go on working indefinitely with the caps that have drifted far from the specs. How that effects the operation is difficult to predict but I guess when Diana Krall starts sounding like a toad in a pond, it’s time to recap. So it’s not unusual for 30-40 year old gear to still operate but those capacitors will not be anywhere near their specs.

Heat/ambient temperatures are the number one determining factor of the life span of the caps. Keep your amps running cool and the lifespan will be greater. Simply put, the law says that life of a capacitor doubles for every 10 degree Celsius decrease in temperature (within limits). Same goes for speakers.

So when Diana Krall sounds like Bob Dillon it's time to recap.

[Charles]

Originally Posted by PHC1

Capacitors slowly degrade over time and there is even a formula out there to calculate the expected lifespan of electrolytics called the Arrhenius' Law of Chemical Activity. Other than a hard failure, a capacitor is considered as failed when it drifts 20-25% from its value. The 10-15 year life span is considered the norm as far as I know but the amp or preamp may go on working indefinitely with the caps that have drifted far from the specs. How that effects the operation is difficult to predict but I guess when Diana Krall starts sounding like a toad in a pond, it’s time to recap. So it’s not unusual for 30-40 year old gear to still operate but those capacitors will not be anywhere near their specs.

Heat/ambient temperatures are the number one determining factor of the life span of the caps. Keep your amps running cool and the lifespan will be greater. Simply put, the law says that life of a capacitor doubles for every 10 degree Celsius decrease in temperature (within limits). Same goes for speakers.

Very excellent reply and information. If one has the money buy the amp or preamp or equipment early in its production cycle and then with the new product do an upgrade. I wonder how much, based on what you have said, is the improvement in sound we are all so pleased to hear is based on new capacitors and simply maybe better parts?

[nicoff]

Originally Posted by 1KW

My Mcintosh 501’s are now 9 years old and still sound and look fantastic and it occurred to me these are not spring chickens anymore. Do capacitors on these last longer than past models ? Any maintenance needed? They really make the Strads come alive, much more weight and “umph” than my Elipsa ‘s with the amps. .

They are no good anymore. Have zero resale value. If you try and sell them you will likely be sued for millions of dollars. You should strongly consider giving them away. It turns out that I am willing to take them off your hands and will cover the shipping. It will cost you nothing. Seriously consider it.

[PHC1]

Originally Posted by Charles

Very excellent reply and information. If one has the money buy the amp or preamp or equipment early in its production cycle and then with the new product do an upgrade. I wonder how much, based on what you have said, is the improvement in sound we are all so pleased to hear is based on new capacitors and simply maybe better parts?

Do you want a philosophical, hypothetical or a practical answer?



Practical: If the absolute performance is of paramount concern, then of course it would be wise to upgrade "once in a while" if the opportunity presents itself for a better performing unit with fresher, tighter spec and quality components.

Hypothetical. My intuition tells me the performance of gear over time follows a parabolic curve. Break in/Burn in phase followed by the maturity and stabilization of all circuits slowly but surely reaching some peak at some point in time. Following the peak, the performance starts to slip down the parabola slope as the capacitors start drifting out of spec. Much like a fine bottle of wine or other spirits which needs to mature, come to full flavor and then slowly fade away into vinegar and acid...

Philosophical: Just as the caps slowly degrade over time making the transition virtually unnoticeable, much like we all age over time, the phases of "wow, oh wow, holy crap this sounds good" and other adjectives describing the "initial phase of performance", the "initial excitement phase" slowly transitions into the phase of a "long term" relationship where those adjectives now morph into "reliable, old friend, served me well for a decade, I don't have the heart to sell this amp after all these years.... etc..." At this point there may be some signs that the gear does not sound quite as good as it once did (speakers/amps/preamps) but we often don't even notice as the emotional bond is much stronger. It's our nature to get attached to things that served us well, imagine trading in your spouse for a newer model at the first signs of coughs, grey hair or other signs and reminders that we are no longer the young, full of life couple we once were.

[LarsT]

It’s a good thing I don’t trade in wives like I do amps. I thought I was going broke swapping amps. The thought is too ugly to even contemplate.

[PHC1]

Originally Posted by LarsT

It’s a good thing I don’t trade in wives like I do amps. I thought I was going broke swapping amps. The thought is too ugly to even contemplate.

You have no idea. Not that I "traded" my ex-wife in.

[Vmax]

Since this thread drifted. So with amps it is bi amping or tri amping for extra fidelity up top, middle and down low? What is the term if you fail to swap out wives and still need extra.

Buy tramping or tri tramping for maximum infidelity?

[1KW]

Good information. I don't think there has been any deleterious effects on the sound but rather they seem to still be sounding excellent. What Serge says however makes a lot of sense regarding the life span of capacitors. I have never been able to make these amps. feel more than slightly warm not hot. I have to agree with Ivan, it must me his handles