Abal - any piece of gear sounds better after few minutes but sometimes it is combined effect of, for instance, speakers sounding better (tweeters' ferrofluid getting warmer etc). In case of the class D it probably achieves full temperature of output transistors faster than class A (smaller mass to heat-up) but it is not even relevant here since time (duty cycle) and not the voltage is important parameter here (before passive low-pass filter). Output Mosfets, if anything are slower (less accurate) with temperature.
Your fast is your amp f rom 0-60 .?
I have noticed that there is a very noticeable delay in my DA-60 Jadis integrated before it will utter even a muted distorted mumble never mind sound good. The time always seems too long. There is no doubt that the automatic biasing mechanism which I see as being a single voltage delivered to the filaments of each tube and does not employ any noticeable feedback regulation. This type of biasing is not true bias but an automatic voltage level delivery system circuit.
The true turn it on and watch the amps bias based on the output for any given input level can be seen in Woolcotts and Audio Valvle for instance.
The Slow/soft start my amps go through is merely a protection circuit as best I can tell, to ensure that electrical inrush is muted and it must go through a slow, stepped up, variac like start.
My other amps Cyber 800 Consonance monoblocks again declare it a self biasing amps but the tubes this time warm up from that ice cold distorted sound to tolerable in less than a minute the Jadis is about 2 minutes. I am not going to touch the optimal time to good sound. In terms of plain old listenable sonics how fast do your amps get up and smell the coffee.
(this is not a comment on slew rate)
The true turn it on and watch the amps bias based on the output for any given input level can be seen in Woolcotts and Audio Valvle for instance.
The Slow/soft start my amps go through is merely a protection circuit as best I can tell, to ensure that electrical inrush is muted and it must go through a slow, stepped up, variac like start.
My other amps Cyber 800 Consonance monoblocks again declare it a self biasing amps but the tubes this time warm up from that ice cold distorted sound to tolerable in less than a minute the Jadis is about 2 minutes. I am not going to touch the optimal time to good sound. In terms of plain old listenable sonics how fast do your amps get up and smell the coffee.
(this is not a comment on slew rate)