Component Break In. Truth or Fantasy

In one respect, it doesn't really matter, you put a new component in your system and play it-whatever happens will happen. Whether it "breaks in" or not is utterly beyond our control.

I have a resolving system and I have a fair amount of experience, and my hearing is slightly above average for a 68 year old, and I've never noticed any dramatic changes-if others do its not for me to argue with what they hear-how could I know and why should I care?

On the other hand, its a bit disingenuous, to say the least, to suggest something on the order of "we should all trust our ears, but if you don't hear exactly what I hear, your ears or your system are not to be trusted" That's a bit of a debating trick to advance dogma that can't be proven or disproven.

It makes sense (at least to me) that mechanical devices might have a "break in" period and I've noticed that, but nothing dramatic. I think science tells us that expectation bias is real and that, over time, our brains accommodate to changes in the sound brought on by new components. I've noticed that subjectivists-of which I am one-often simply ignore these seemingly well-established occurrences, perhaps because they are inconsistent with our belief system concerning this stuff. For me, I suspect that's part of it-but maybe somehow electronic components do "break in" and maybe the sound almost always improves as it changes, which seems odd, but certainly possible, I suppose. 

I have an open mind on break in. Less willing to accept. the assertion that anyone who has not heard dramatic differences as new components age means their ears or their system is somehow primitive compared to those who perceive something different. 

I think I'll trust my ears.

Whether it's break-in or just an accommodation to the sound, it seems the bottom line is wait for a number of hours before you decide whether or not you like your new gear. 

Yes - electronic components have a settling time, which can vary significantly depending on the component.

Most 'Break In" is done in the R&D phase of electrical, EM components . 

Truly what audiophiles and hobbyists are doing is what I would call seasoning and this is more of a psycho acoustic process. Yes it's in your head. I do it too!

How it Works (Burn-In Testing)

• Accelerated Stress: Components are subjected to temperatures and voltages higher than normal operation, sometimes with humidity, for hours or days.
• Simulates Years of Use: This stress mimics years of real-world use to quickly reveal weak parts.
• Static vs. Dynamic: Tests can be static (constant conditions) or dynamic (changing inputs).
• Identify Defects: Catches issues like electromigration, dielectric breakdown, wire bond failures, and material degradation.

• Manufacturing Defects: Flaws in semiconductor fabrication or assembly.
• Packaging Issues: Cracks or corrosion from thermal stress.
• Material Degradation: Chemical changes in materials over time.
• Environmental Factors: Moisture, humidity, and extreme temperatures.
• Electrical Stress: Over-voltage, power surges, or ESD (Electrostatic Discharge). 

• Reliability: Ensures only robust components are used.
• Cost Savings: Prevents expensive failures in final products.
• Warranty Reduction: Lowers failure rates, extending product life. 

• Audiophile "Burn-in": A controversial practice where new audio gear is left on to supposedly improve sound quality, though often debated.
• Actual Circuit Break: A physical interruption (open circuit) or short circuit, usually due to corrosion or damage, causing malfunctions. 

I had read somewhere that audio equipment sounds better after 100 hours of burn-in, so I tried it. I definitely noticed a difference (i.e. everything sounded much better to me), so I routinely do it no matter what. This rule of thumb also works with breaking in acoustic guitars, too.