Does Equipment Break In, or Does Our Hearing Adjust?

I’ve read many comments about how the sound quality of equipment improves after so many hours of use.  I don’t doubt what people are saying.

About a year ago, my wife and I were tired of not being able to hear dialog while watching TV.  Especially when there was background music or noise, we had a hard time hearing dialog.  Turning up the sound helped, but not very much.  The sound of the TV sounded normal to other people visiting us.

We bought a Zvox sound bar.  Setting it up, we could hear the dialog, but it sounded very tinny, almost irritating.  But that disadvantage was outweighed by being able to watch TV and hear what was being said.

Now, a year later, we can still hear the dialog, BUT, it doesn’t sound tinny anymore.  The voices sound normal, like people we talk to in real life.  It’s not irritating in the slightest.  This happened gradually over a year, so we didn’t notice it until we thought back to what it first sounded like.

My impression is that our hearing adjusted or became used to the new tinny sound.    Or, maybe the sound bar broke in to sound normal. But if it broke in to sound more like normal, I would have thought that it would lose the special effects that enabled us to hear it better.

Or even, maybe it was a bit of both?  Any thoughts?