Joab blew the trumpet and restrained his troops after killing Absalom to end the battle between David's servants and Absalom and all Israel. (2 Samuel 18:16)
Sheba blew the trumpet to lead Israel and Bichrites away from David after he was brought back to Jerusalem after Absalom's conspiracy. (2 Samuel 20:1-2, 2 Samuel 20:14)
Joab blew the trumpet to end the siege against Abel of Beth-maacah once he had received the head of Sheba, the son of Bichri, who led a rebellion against David. (2 Samuel 20:22)
Jesus will return with the sound of the trumpet of God
Through Jesus, God will bring with him those who are asleep. The Lord will descend from heaven with a cry of command, the voice of an archangel, and the sound of the trumpet of God, and the dead in Christ will rise first. Then the living will be caught up together with them in the clouds to meet the Lord in the air and will always be with the Lord. (1 Thessalonians 4:13-18)