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

Resistance and capacitance are some of the electrical properties that change with temperature. For the electronic equipment to be able to properly measure and provide accurate and consistent results, these instruments must warm up and stabilize thermally. Some argue that ‘warm up’ may not be the right term to use, as some devices sometimes need some time to stabilize thermally.

If you look at Sterophile's test measurements, they always warm up or per-condition the equipment prior to testing.

Is there and white paper that explains this "shkong"?  I am a believer I just dont know why? 

+1 to @testpilot

Especially Dac is sensitive to stabilized temperature.

Some Dac need at least 24 hours for optimal sound.

Thus I leave my Dac on 24/7 on.

But I never leave tube amplifier 24/7 on.

You will end up retubing in a month.

And " cleeds2" is right. Everything is better with beer. With the exception of tomorrow,

Your perception of loudness changes as a protective measure so you dont blow out an ear drum... It will not stop over pressurization in the "Specta Inner Pinna" of the ear. But it will try to compensate. The Human anatomy is a pretty amazing thing. I think John Dunlavy tried to understand this as he was designing speakers.

https://www.google.com/search?rlz=1C1CHBF_enUS748US748&sxsrf=ACYBGNT8XkRSthE_IWMeI9vklf0kumzjNg:1579010452679&q=Specta+Inner+Pinna+ear&tbm=isch&source=univ&sa=X&ved=2ahUKEwj2mIOpoIPnAhVRu54KHSEYC6oQsAR6BAgIEAE&biw=1600&bih=757

haywood310

I know there is brain conditioning that happens with sound waves and your ears sending electrical impulses..

That’s interesting.
How do you know that?

I know there is brain conditioning that happens with sound waves and your ears sending electrical impulses... be interesting if any ear specialist have tested this with Audio systems. Agree 100 percent with "
bsmg" Tubes are a different animal all together. I have had my share.

Yup, this is what we need, yet another thread on a well-worn topic:

How long daes it take your gear to warm up?
Warm-up time for amps and preamps
Is it the beer or do speakers/electronics really need some extended warm-up period?
Speaker Break-In - What Physically Changes During Break-In To Enable Better Sound?
Burning/breaking in new equipment?
Do Interconnects need to "warm up"?
Equipment Break-in: Fact or Fiction
Break in blues
Value of burn/break in?

... and the list goes on and on and on and on ...

For SS devices, I see no rationale for any sort of warm up period. For vacuum tubes, this is not the case. It takes about ten minutes at least for tubes to stabilize. My amplifier has separate LED's for each output tube for bias adjustment and it takes about ten minutes for all of them to light up indicating that they are at their required voltage state and never do all four of them light at the same time; each reaches its operating parameters at different times after being energized. There's probably also some "warm up" rationale for conventional cone type speakers in the sense that the stiffness of the surrounds as well as the cone structure itself will "loosen up" after a period of time, but the speaker has moving parts, so this is a rational assumption. Same thing with the engine in your car; it's not at its optimum operating state immediately after start up. And this is all a layman's opinion. 

Some components operate at their peak performance at a specific stabilized temperature.  The same way an athlete warms up prior to competition or exercise.