ipod sound separation on headphones

[CubaTBird]

I notice when i listen to old songs on my ipod, like the beatles or frank sinatra, there voices come out of one ear bud while the instruments come out the other, why is this?

 

[AliensAreFuzzy]

That's just how some songs are made. The right channel contains all of the vocal while the left has the intrumentals. or vise-versa.
I know that some of my new songs do that too.

 

[applemacdude]

Its fun trying to listen to pink floyd on one headphone...