Break in period

Cycling on and off actually helps to form the electrolytic in the power capacitors. I have never had any problems as a result of turning off equipment when finished listening to it. This on/off fear thing is way out of control. Save electricity, reduce the chances that something will hit the power grid and fry your stuff, and turn your gear off when left unattended.

The CT5 will take at least 400 hours for it to sound its best. The folks at cj will say 200 hours, but both the dealer's and my experience showed it to be longer. It is true that it will start to sound better at 200 but the best is yet to come.

advice of fellow a'goners regd optimal break in period and is the break in period dependent on playback volume or amount of
gain.

I will re-iterate what I normally say to these threads; well designed audio electronics equipment and cables should NOT drift significantly (i.e. audibly) between the time you plug it in and a few hundred hours. Of course, things age with time, heat, stress etc. but useful product lives are usually measured in numbers of years...

As to reported vast differences after a few hundred hours => either this is perception as the ears/brain are more familiar with the "sound" (it is well known that musical hearing ability can be improved with training/repetition) or it implies a badly designed piece of gear...(linearity, stability and reliability of ouput signal over time is a primary requirement of an audio product)

"I will re-iterate what I normally say to these threads; well designed audio electronics equipment and cables should NOT drift significantly (i.e. audibly)
between the time you plug it in and a few hundred hours."

laudable belief. Unfortunately reality is impervious to our wishes, beliefs, opinions or otherwise. Things either are or are not, regardless of what we believe they 'should' truly be. I have no beliefs on the subject, but only modest experience with just a few components. My ARC Ref 3 improved dramatically from 0 to 150 hrs, significantly up to 400 hrs, and subtly up to 550 HRS; its 6550 rectifier tube started to deteriorate at approx 1300 hrs and I replaced it at 1900 hrs; its replacement stabilized at 70 or 80 hrs. My X-01 Limited became listenable only after 200 hrs, was quite good at about 400 hrs, excellent at about 800, but kept improving subtly until about 1200 hrs. Different equipment may behave differently. . . or even worse, I may be totally delusional.

Buy some cheap output tubes and run the system a lot, not continuously. Keep the cheap tubes for emergencies later. For $50 to $100 bucks, you will get a piece of mind.