It takes music to open up a tube preamp/amp

That's exactly what I get with my cj premier 14 so I don't think your crazy..

Have you ever given any thought to the fact that the human ear/brain processor is a very adaptable system and that your are the one adjusting to the sound regardless of what the equipment might be doing insofar as warming-up and, yes, breaking-in are concerned? I didn't think so, because it takes out so much fun factor from audio does it not? I know, I know: you can distinctly hear it so it is there. Funny how you do need positive reinforcement from other audiophiles though. Seems one can never be too sure whether that phenomena picked-up through casual listening actually does exist, right? Can't go all the way, however, and have anything confirmed by a panel using some kind of procedure offering repeatable results. Certainly not as this would go against the central tenet of subjective audio which holds: "to your own ears be true" and its sub-paragraph which reads: "to be confirmed only by other true believers". Yes indeed, electronics that have not played music in a while are out of practice and need to go through the paces prior to the stage lights being shone upon them. Nothing short of music will do. Did you notice that if you are listening to chamber music, a warm-up with any other type of music just does not do it? The soundstage is just not right, the individual instruments cannot be correctly located and PRAT is negatively affected? I have found that if a recording uses a Gibson guitar, warming it up with a recording of, let's say, a Fender, Hamer or Guild will not do it? For the genuine Gibson sound, insist on a Gibson warm-up piece. Equipment is so sensitive these days that you should never, ever say anything within earshot that could affect their sentiments, as the price to be paid is a loss of emotion in its musical presentation.

Moreover, the cartridge also worms up and plays better on the next record or the next side of a record...

In other case for me having mostly records mid70's...end80's to play some mid-60's after all I usually listen, does make me believe that back that time the recordings were far more superior...

Idle or stand-by may not warm up the tubes and other parts as much as working harder with a signal. Dont think your imagining the change but there are some people who will never accept differences without specs and graphs to back them up. I believe your brain can change the way you "hear" different aspects of sound, but thats not -always- the cause of a change.

I don't know. I've elected to leave everything on. I'm sure everything will last longer, especially the tubes. (No heat-up/shrinkdown). I acquired this habit from being an audio engineer prior to being an audiophile. Every studio, busy or not, kept everything on constantly. (Except mikes).