component break in

The recommended break in period for my speakers exceeds my life expectancy. I was not told this when I purchased them.

It really depends on the item. When I got my new original Dynaudio C1's I was told they need about 350 hrs to sound their best. I had never run into anything like that before. Anyhow out of the box they sounded great. BUT between 100 - 150 hrs they really sounded horrible. Highs were rolled off - bass was rolled off - mids got very shouty and I just wanted to cry. Magically just after 150 hrs they started to sound good again. At about 200 hrs they really sounded great and at 350 hrs finally settled down and sounded fantastic.

Now the only other things I have found to take a longer time to break in were new power cords and new vacuum tubes. Typically around 200 hrs. On the other hand my cdp only took about 25 hrs.

That has been my personal experience

I found only speakers really had noticeable breakin.

Pretty much no matter the component or wire I'll give it 10 straight days of it being on constantly and/or having some kind of music or signal being sent through it. Then I'll give it a critical listen. If it doesn't sound good after all that I'm selling it or returning it.

I came up with this from a lot of stuff I've read. Be it reviews on the net or the actual instructions that came with the item. Pretty much everything I've come across requires 150 to 200 hours of break in so I figure why bother with trying anything different. Just give it over 150 hours then give it a critical listen. When I had a short time to audition or return I'll do something along what Elizabeth said about giving it 3 days.

Everything in the I can ever remember buying usually sounded good enough when I brought it home from a dealer, to know I was happy. Any changes I heard were mostly subtle.
In other words, I knew whether I could keep it or not, at the beginning, or in a few days.

Equipment I've bought without hearing, still gave me an idea what I had to deal with, at the beginning. If it was too questionable, I usually let it go. When I heard that same equipment somewhere else, years later (well broken in), I recognized those same characteristics I didn't like years earlier.

I'm not saying it doesn't need broken in, just be careful if it bothers you that much. A few days should give you a good idea, and time for you (nerves and excitement), and the equipment to settle in. It may not be a keeper, if it still is questionable.