What is it.........

Mom's home cooking.

I have experienced that many times, and I believe that it is for 2 reasons. First, I have read over the years that car acoustics are good in general, and second, I think car listening supresses the bass and treble, and brings the midrange very close so that you feel that you can hear things very clearly that you don't normally hear in the singers voice and other midrange details. It isn't as smooth, lifelike, textured or well balanced and dynamic as your home system, but yes, it can really communicate emotion at times! 

Sorry, I cannot relate to this post. I cannot think of a single instance where any music played on an inferior system, much less a radio, was more moving, compelling, soulful, etc. than on my finest system. 

Imo, emotion or soul of the song is not conveyed well on poor audio systems. YMMV 

There are songs that sound great in the car that I will never listen to at home.Black Sabbath,Ted Nugent,the Cars(ha!),etc.

Cranking tunes in the car is just fun in a way home listening isn't neither is better or worse just different. I always sing in the car I rarely sing along at home. Plus fewer distractions in the car, except for when there are more.