I’ve read electrolytic capacitors wear out and need replacing from time to time, but after how many years?

I recapped my speaker crossovers after 27 years, but they still worked - they just sounded better afterwards

My NAIM 5i just stopped working after 10 years..

But I ask - why didn’t my 20 year old Denon stop working with the same problem or even my 30 year old Yamaha receiver that I passed onto my friend. Both are STILL working great!

My Luxman L530 class a/b amp still worked when I sold it after 11 years

So is it the circuit design (high current design) that causes the caps in the NAIM to wear out so quickly?

Does the loud "discharge" thump when initially turned on (specific to NAIM Gear) cause premature wear

Should I not have left the amp turned on 24/7 ? (which I only did for about half of those 10 years)

Is it related to the parts that NAIM uses?

Would having better quality capacitors (like Mundorf) last longer?

Seems strange that much cheaper amps and receivers have a longer lifespan

It would be nice to understand why this occurs with "some amps"

Thanks for any feedback - Steve

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The electrolytics are what wears out, and the 1980's are a lot worse than the 2000 era caps.

High temp caps wear less quickly

Life of electrolytic capacitor, temperature is the No.1 factor, follow by applied voltage, and the applied ripple current load .
im, that is only aluminum electrolytics in power supplies. It does relate cap life to heat but in a very non specific way. Recapping the power supply of a hot amp (class A or tube) after 20 years is probably a safe bet. Easy to do. This does explain why small receivers might last longer. They do not get so hot. 
If, as it appears to be the case, heat plays a role, then surely it is better to turn gear off when not in use?

e.g. Naim recommends leaving their gear powered on....
- Could this be simply to make it more convenient to their customers because they do not want them to have to wait for the gear to "Warm Up" before it sounds it’s best ?
- Or is there less "stress" on internal components (e.g. Caps) when left on 24/7?

I cite my Denon and Yamaha receivers again - they have lasted a long time
- is it due to powering them down?

I have always assumed that higher quality(i.e. having a higher price point) gear uses higher quality components, e.g. as one poster above states WRT Bryston gear.
- But do some quality caps that sonically perform better, actually fail sooner, compared to the "run of the mill" capacitors used in more budget oriented gear.

Could it be that, "mass produced" Caps, that might not perform quite as good as more specialised products, are subject to more stringent QC because higher failure rates in mass produced products are less acceptable?
- e.g. higher quality caps in Mass Market products might result in high return rates - not good
- mass produced caps might last longer and the lower quality sound is seldom noticed

I cite several posts on this forum, where people have replaced a myriad of components to achieve higher quality sound

I used to work for a company that produced circuit boards for the mass market and their QC was of the highest order. Component failures were analyzed by teams of experienced professionals that recreated the many scenarios under which components failed. Once determined they then tried different components until the most reliable solution was found.

But in the world of audiophilia, sound quality is paramount and the smaller companies do not have the resources to undergo such a stringent QC approach.

Do Audiophiles "accept" the fact that their gear might not be as long lived as more commercial products?

Many Thanks
The triad for life is heat, age and ripple.

Do Audiophiles "accept" the fact that their gear might not be as long lived as more commercial products? 

Compared to what, a stove?  A blender? A car?

For consumer electronics I think it's the other way around. What piece of consumer electronics are you not going to fully replace in 10 years or less? Your PC, Phone, networking and TV gear has an average home life of 5 years, don't you think? We're going the other way, we're trying to keep gear running long after the product has ceased production.

The life span of a capacitor depends on the voltage it sees and the temperature of its environment. For example, I had to recap my 15 yea-old at the time Audio Research 100.2 because a couple of the power supply caps were bulging. The reason was obvious: the capacitors were rated at 50 volts and the voltage rails are 50 volts. So the cap's lifespan was shortened because it was operating at the voltage margins. I replaced them with 63 volt caps so that their lifespan will increase by 50% in that application.

On the other hand, my 1970's 30-watt Marantz receiver's power supply caps test as practically new. That's because their voltage rating is much higher than the rail voltage and there is practically no heat generated inside. Still sounds great.
Go figure. Lots of use prefer the sound of class A and Tube amps and accept the fact that they may not last as long due to the heat and we never leave them on mostly because we do not like supporting Mr Edison. I see no problem leaving a class D amp on. Leaving electronics on prevents heat cycling. I leave my Adcom amp on continuously along with its preamp. Of course the preamp got taken out by a lightening strike. But, that is what full replacement insurance is for.  The amp is now .....42 years old powering the workshop system.