It is not mere sound that crowd is attracted to. 

A certain charisma and more importantly an extraordinary ability to transmit and arouse the sexual energy like a loop between the audience and male/ female performer. 

I asked a friend once why don't you listen music in the phone or radio than buyng expensive concert tickets. He said the energy in the concert is way amplified than what we listen in speakers or in radios. 

The energy in the concert penetrates every cell in the body and mind of the listener, and it is amplified million times by concentrated and synchronized energy vibrations of hundreds and thousands of people and the performer. The electronics is last minor tool to be blamed, even before the sophisticated electronics invention, this psychic mechanism was going on, electronics made this effect even more pronounced. 

Some people change the flavor to religious music and use the power of music or sound addiction towards their respective missionary goals, however gross or subtle or sweet or bitter the music is, the end result is strengthening the music addiction. As long as the sound does not neutralize the mind like silence or naad, the sensual music will keep demoting the mind to grosser and grosser levels.