How to Crossfade One Song into Another in iTunes
iTunes let you crossfade one song into another. DJs in clubs and on the radio often make a smooth transition from the ending of one song to the beginning of the next one. This is called a cross-fade. Ordinarily, iTunes is set to have a short cross-fade of one second (the time after the fade-out of the first song to the fade-in of the second), but you can adjust that if you like.
You can change the cross-fade by choosing iTunes→Preferences on a Mac or Edit→Preferences in Windows and clicking the Playback icon. The Playback preferences appear.
Select the Crossfade Songs preference and then increase or decrease the cross-fade by dragging the slider. Each notch in the slider represents 1 second. The maximum amount of cross-fade is 12 seconds. With a longer cross-fade, you get more overlap from one song to the next; that is, the second song starts before the first one ends. To turn off the cross-fade, deselect Crossfade Songs.