The singers reply with the opening notes of their own parts, and then the song begins immediately.

The opening notes were removed and the work was re-arranged in 2010.

The tentative opening notes of the music suddenly flowed through the hall.

The busy signal became the opening notes of the song.

McGuire smiled as if the sounds were the opening notes of a favorite symphony.

The Simpsons has used the opening notes of this theme in multiple episodes over the years.

When a man and woman enter, the symphony's opening notes are heard.

In music, it can also refer to the opening notes of a musical composition.

The arraignment of the two struck the opening note in what promises to be a spectacular trial.

That sounds like the opening notes of a con song, Sergeant.