Can anyone explain in laymans terms why your gear sound better after warm up

I get burn in... should be called burn off just to get the manufacturing process off all the different manufacturers and parts to sweat off the packaging and sealants. But a light bulb is on or off. So SS gear in theory should sound the same. A light bulb does not get brighter after an hour. Is it your ears get programmed? Or is there and actual technical reason that it sounds better? Please pretend Im a four year old cause with Electronics I am.

Thank you for your patience and perseverance hanging around reading all the, uh, comments above. This is your reward.

First of all, no one really knows for sure. This goes for a lot more than warm-up. Heck it goes for pretty much everything! Soon as you hear someone telling you why, run for cover, its raining ad copy. The best we can do, at least for the time being, is talk about things we do know for a fact are happening and show how they "could" as in "maybe" account for what we are hearing.

That last bit right there is the most important thing to know, by the way. We go by what we hear. Its up to the guys with the degrees to figure out why and how it works. For us its enough just to be able to hear. More than enough.

Okay. So what we know for sure:

You pass a current through a wire, it simultaneously creates an electromagnetic field around the wire. We don't want our wires crossing and shorting out and burning all over the place so we put insulators around them. Then we notice none of these insulators are perfect. The perfect insulator would be like a vacuum, allowing the magnetic field to rise and fall without disturbance. The imperfect insulators we all use aren't like that at all. They all absorb a tiny bit of that energy and then radiate it back into the wire with a delay. The result is a sort of smearing of the signal.

There are ways around this. One is better materials. Expensive gear uses some pretty expensive dielectrics, as electrical insulators are called. Another method is to charge the dielectric. Synergistic Research use this thing called Active Shielding that put a 30v constant field around the wire. It had many benefits, one of which being the steady field helped maintain the dielectric in a state of steady charge. Obviously if the dielectric is absorbing and radiating it has less ability to absorb the more it is already charged and "full" and so it works better this way.

Get it? This already is more than enough information to figure it out. No? I'll keep on then.

Anything with a wire and insulators just sitting around has time to dissipate whatever charges it had developed when running. So then when turned on the first thing that happens is all those dielectrics start the long slow process of charging back up. Simply being turned on does a lot. But audio signals vary tremendously in amplitude and frequency. It can take a while for all this complexity to saturate to the point of equilibrium. 

This more than likely is what is going on. This explains why tube gear can be turned off and will warm up fairly quickly. The insulator in a tube is indeed a vacuum. Electrons boil off one plate and flow to another, with the flow being controlled according to the signal, which is why they are sometimes called valves. Once the plates heat up and reach equilibrium the tube is warmed up. This also explains why SS gear needs so much warm up and is often preferred to be left on. SS uses transistors and circuits in which the mass of the dielectric not only is not a vacuum, it is very large and massive relative to the tiny conductive circuit.

This dielectric saturation theory may not be correct, but it accounts beautifully for what we hear. It explains why the longer gear is off and the sooner after its on you hear it the worse it sounds. It explains why the bulk of warm-up improvement happens the first few minutes, and why it continues to improve at a more gradual rate for quite some time.

And all in layman's terms. So there you go!