Debate: Class D amps need 48 hours of warmup

Seriously, no noticeable difference between dead cold and having been on continuously for days. My Hypex amps just don't require any coddling to perform. Hit the switch and listen...no worries. 

I find that the sound quality of all of my components, not only my integrated amp, benefit from at least 15 minutes of warm up after going into play mode from the standby mode.  Improvements in sound quality after warmup compared to cold play are minimal but audible, expressed in nuances such as ambiance, decay, secondary harmonic, and imaging details.   When away or when there is a thunderstorm, the system is shut down and unplugged.  Warmup then takes at least a half hour.  Changes in all areas of sound quality after warmup compared to cold play are moderate and noticeably audible.  

So I really should have asked how many people have actually tried this?  If you leave them on all the time, have you powered them off ?  If you don't, have you tried leaving them on for a couple of days? 

@erik_squires We have a few reports of our class Ds sounding better if left on all the time. I've not experienced that myself. They seem ready to go as soon as I turn them on. My preamp, which is tube, seems to need a bit longer (20 minutes it sounds more lifelike and after an hour its gotten to where its going) before it can be taken seriously. 

In both cases there's no degradation if left on. 

OK, guys, I know this is sounds like a weird question, but lets’ not attack the replies, or even the author, until we’ve seen informed replies.  This kind of judgementalism is really not what I was looking for when I posted. 

Not an attack at all, maybe to the manufacturers if they create an amp with a 48 hour warm up time to sound good. 

I have heard from dealers that they can hear a difference in the sound of amplifiers that had been powered off when the store was closed for a few days and that they return to optimal after 48hrs.  

This begs the question- how does optimal compare to our usual "startup" period when it starts to sound  good?  My amp and system sounds great after 20 to 45 minutes or so- whether tube, class AB or Class D.  I am completely satisfied with the sound after that. 

Since I have never left electronics on longer than 12 hours or so- I do not and probably will not ever experience a 48 hour warmup.  Is the original question 48 hours to sound good? 

I have owned a variety of pretty good amps in Class A, Class AB, and Class D, but not tubed amps except for Lamm's hybrid M1.2 Reference (one tube each).  Of the amps I enjoyed having in my system, they all sounded pretty good within a few minutes of powering up and good enough that warmup was never a consideration after they had been playing music for about 30 minutes.  If I couldn't ignore the gear and enjoy the music after 30 minutes, I would question whether I actually liked the sound of the amps in the first place.

When I had Class D amps, and with my current my Class AB amps, I rarely turn them off except for thunderstorms, vacations, and long weekends away from home.  I did turn off my Clayton M300 Class A monos most days, and those are the amps I owned that probably benefitted most from warmup but still, 30 minutes or less and I wasn't thinking about warmup.