Here is my experience: If a component does not sound good "out of the box" I do not believe any amount of break in will change my mind. However, I notice components open up a bit more after some hours of playback. Now, I'm not into the 500-800 (or whatever) hour deal, but I think things slightly improve with a few hours of playback. The rough edges (floabt) smooth out.
In my original post I was wondering if volume has an effect on break in or is turning on the component with low volume sound enough.
Correct. As I have noted many times- if its good then its good right out of the box. Everything will of course change and improve over time. But the essential character heard from zero will always be there. If not, if you don't like it right away, don't waste your time.
There really is no debate about break-in. There are only people who have never bothered to either develop the listening skills to hear it, or even taken the time to try. (You can for that matter replace "break-in" with power cord, interconnect, any number of things, and then write the exact same sentence.) The debate is settled as far as "does it happen" and only "can you hear it" remains.
The biggest challenge for most is just learning to listen and hear it. For those who wonder, here's what happens: the first few minutes running the essential character is there but grainy and harsh and lacking fine harmonic structure, subtle nuance or detail. Within minutes this etched skeletal quality begins transforming becoming much more smooth and filled out and liquid. Dynamic shadings nowhere to be found in the beginning become plainly evident later on. Eventually if the component is good enough it gets to palpable presence, that eerie feeling where there are so many subtle details coming through so effortlessly its like you are feeling it more than just hearing it.
For people like zarathu who find this impossible, well isn't it odd that I am able to explain so clearly and in such detail what you think I am not even able to hear? The simplest explanation is I know what I'm talking about, however hard that may be to believe.
But hey, another thing I'm constantly saying: DON'T TAKE MY WORD FOR IT! Go hear for yourself.
Take whatever fuse you have that is easily replaced and swap out it out for one that is brand new. The brand new fuse will have zero hours on it. First make sure everything in your whole system is on and thoroughly warmed up. The same crappy sound you are going to hear from the new fuse is the same crappy sound you are going to hear from cold anything. So warm it up. Sit back and listen. Then swap the fuse and listen again.
Then when you get to where you can easily hear such things, repeatedly and reliably, then you will be in a position to say that no, the volume level does not matter. What matters more than anything else is time. The vast majority of burn-in improvement occurs in the first few minutes to hours. Beyond that many components continue to improve some of them yes for a hundred hours or more. But the vast majority occurs right away, and so fast you will if you are a good listener be able to hear it on the fly as it happens.
Then once you get past the first few dozen hours or so, somewhere in there, the warm-up factor starts to come into play. You can think of this as whenever anything is turned off more than a short time, overnight say, it is almost as if it goes back to being like new again. That is to say, when you first turn it on it is not going to sound very good. But then within a fairly short time, could be 10 minutes, could be an hour, its going to stabilize and sound great again. Instead of burned-in we say warmed-up but it is the same only different, as they say.
