Debate: Class D amps need 48 hours of warmup

@erik_squires +1  "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."

My tube pre-amp has a one-minute soft-start.  My Class D does not.

Hard to definitively answer... Both sound fine as soon as they are 'on'.  Both sound a little better after a few hours of use, which is usually at night, which is confounding...

I do not leave my four Pass Labs amps on all the time due to the high bias they are always in class A.  Although I expect the input stage is still idling and the heat sinks are cold.

When turned on the heat sinks start "tinking" and when they are done with that I'm good to go.  But it does get better after that warmup and continues to get better. I believe its my ears/brain just settling in to the groove.

As an aside, although subjectively they sound better I have put sensitive thermometers on the heat sinks and after no more tinking the temperature remains stable at ~109 degrees.

Regards,

barts 

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.