Booms
The fireworks last for around 35 minutes and feature over 15,000 fireworks shells.
Starting in the late '90s, howitzers from the nearby Wisconsin Army National Guard have been used in the finale, which features Tchaikovsky's 1812 Overture. The howitzers fire blanks along with the recording, filling in the cannon shots called for in the score. Although the howitzers make a different sound than the exploding fireworks, it can be difficult to hear them due to the continuous noise of fireworks overhead throughout the finale.
The fireworks' mortars are fired by computer, ensuring synchronization of the fireworks and music.
Read more about this topic: Rhythm And Booms