What's the ideal stereo mix?

I listen to CDs and some mixes are OK, some a bit irritating.I listen to some individual instruments, but never pay attention to exactly where that sound is , left or right or middle. Is there some kind of science to it? satan?

You put the singer near the middle and the other shit sprinkled around.

To expand on Richs’ answer: typically, you’ll find a solo instrument centered (voice, violin, whatever) along with the instruments at the lower end of the frequency spectrum (bass, kick drum, timpanies). The other “shit” should round out the mix as though you were standing in front of the band/orchestra.

The piano is usually stereo, gradually moving from left to right split at middle “C”. Drums, too, are mixed to both channels based on the placement of individual pieces placement on the stage.

Quite often these days, with the advent of chorus, reverb and delay effects, most instruments are actually overlayed in both channels but are more pronounced in one.

Of course, don’t tell this to (Beatles producer) George Martin. I can’t think of the song at the moment, but he placed the drums and vocals on one channel and everything else in the other. “Drive My Car”, maybe?

Anybody remember that fake stereo that some old songs originally in mono were remixed in? I seem to have a button on my stereo that does that.
Some stuff obviously does not work well on headphones, that Drive My car included.

I think I understand this but heres my ovbservation. In the music I listen to, I have come across songs that sounded like the mixer tried to give an effect of the sound going back and forth between speakers. Quite odd, but interesting. When I first heard this I thought it was a mistake, but couldn’t be because the song before and after was even between the speakers

You make me want to throw my pager out the window
tell MCI to cut the phone poles
break my lease so I can move
cause you’re a bugaboo, a bugaboo