When you listen to stereo speakers, you always hear both channels with your two ears. Headphones don't have that problem; the left channel is only heard by the left ear, and the right channel only by the right ear. That's why stereo sounds smaller over headphones, and of course it's all, or mostly, in your head.
And once the sound is there, the headphones' job is done, but with speakers you're always hearing the speakers' sound, plus the sound bouncing around the room. The closer you are to the speakers, the more direct sound you'll … Read more