"Wait a minute… Wait a minute… you ain't heard nothin' yet."
In 1927, Al Jolson spoke those words in The Jazz Singer, marking the end of the silent film age. (Of course, that film also featured Jolson in blackface which unfortunately was common at the time.) From The Guardian:
Just a year before (The Jazz Singer), Warners had made Don Juan, starring Douglas Fairbanks and Mary Astor, which didn't exactly set the Hudson river on fire, despite sound effects like the clash of swords or chairs being thrown – all to the accompaniment of the New York Philharmonic.
The reason Sam Warner, the technical genius of the brothers, thought that adding a human voice would make all the difference was a series of shorts brought in as a late addition to the Don Juan programme. Giovanni Martinelli, principal tenor at the Metropolitan Opera, sang Pagliacci. The leader of the Philharmonic played his violin and Al Jolson sang When the Red, Red Robin (Comes Bob, Bob, Bobbin' Along).
They were a secret success. The New York press hardly noticed, but audiences did – and loved them. What would be known as "the talkies" were coming out of the fairground.
It was Sam Warner's idea to team up with the Western Electric company to buy its Vitaphone synchronising system. He had the faith that few others possessed, but sadly died of a mastoid infection of the brain the day before the hugely successful premiere of The Jazz Singer.