How to evaluate amps that are not broken in?

I'm expecting to demo Belles and JoLida amps next week at home, and both units are new. Can I assume that if I like the sound of an amp now, I will like it just as much after it's broken in? How does one account for this variable when trying to decide if a new piece of gear will be synergistic with one's system? Thanks!
there is no reason to assume that if you like the sound of a component when it is fresh out of the box, that you will still like it after 400 hours.

i have had experiences in which i initially liked a component but then did not like it after 300 hours.

very rarely have i had the experience of initially disliking the sound of a component and then liked it after 400 hours.

if amplifiers are not broken in , it is wise to wait until the amps have been played for at least 300 hours before making a purchasing decision.
Sure Mrtennis.
But it is more of the search for the new adventures and boredom with the old then anything else.
However, IMO, our current state of mind i.e. a good (bad) day at work, an argument with the spouse, a good game of golf, a lousy meal, time of day, etc. etc. play a much larger role in our evaluation of any listening session than minor changes in the components.

Break in is mostly due to our ears acclimating to the new component not the component undergoing some incredible transformation.

Ommmm, yes. This is certainly my opinion. Never mind changes in your AC line, your air condition or water heater being on or off etc. The variables are endless, and if you believe all of these things make a difference in the sound-- which would only be logical if you believe in break in-- than you seem to be in a catch 22. How do you prove it with when the environment is constantly changing.

You may think you hear something, you may even be sure you hear something. But the real world variables combined with all the psycological variables, combined with standard EE knowledge that NOTHING has changed should be enough convince a normal person that this is all BS.

Dont you think that the industry might have an interest in saying you have to spend some time with a component before it sounds its best? They are probably right, you should. But their reasoning behind it is fabricated.

I wasted a lot of time over the years on this kind of crap, unfortunately.


Well, I have to admit that I'm totally confused at this point. All of this disagreement re: breaking-in would seem insignificant if it weren't for the fact that audio gear is so expensive. Perhaps the safest route is simply to only purchase used gear, so the breaking in factor is a moot point.
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