Concise Bible Dictionary:

These were made of rams’ horns and perhaps of the horns of other animals. They were used on joyful occasions, and at the wars. There were two trumpets made of silver which the priests used, and instructions were given as to blowing different sounds for calling the princes together, or for summoning all the congregation, or as an alarm for war (Num. 10:1-101And the Lord spake unto Moses, saying, 2Make thee two trumpets of silver; of a whole piece shalt thou make them: that thou mayest use them for the calling of the assembly, and for the journeying of the camps. 3And when they shall blow with them, all the assembly shall assemble themselves to thee at the door of the tabernacle of the congregation. 4And if they blow but with one trumpet, then the princes, which are heads of the thousands of Israel, shall gather themselves unto thee. 5When ye blow an alarm, then the camps that lie on the east parts shall go forward. 6When ye blow an alarm the second time, then the camps that lie on the south side shall take their journey: they shall blow an alarm for their journeys. 7But when the congregation is to be gathered together, ye shall blow, but ye shall not sound an alarm. 8And the sons of Aaron, the priests, shall blow with the trumpets; and they shall be to you for an ordinance for ever throughout your generations. 9And if ye go to war in your land against the enemy that oppresseth you, then ye shall blow an alarm with the trumpets; and ye shall be remembered before the Lord your God, and ye shall be saved from your enemies. 10Also in the day of your gladness, and in your solemn days, and in the beginnings of your months, ye shall blow with the trumpets over your burnt offerings, and over the sacrifices of your peace offerings; that they may be to you for a memorial before your God: I am the Lord your God. (Numbers 10:1‑10): Compare 1 Cor. 14:88For if the trumpet give an uncertain sound, who shall prepare himself to the battle? (1 Corinthians 14:8)). At the dedication of the temple Solomon had a hundred and twenty priests sounding with trumpets (2 Chron. 5:1212Also the Levites which were the singers, all of them of Asaph, of Heman, of Jeduthun, with their sons and their brethren, being arrayed in white linen, having cymbals and psalteries and harps, stood at the east end of the altar, and with them an hundred and twenty priests sounding with trumpets:) (2 Chronicles 5:12)).
The use of trumpets set forth the public proclamation of God’s rights in His people, whether in their direction or in their relationship with Him.
When the Lord Jesus comes to fetch His saints it will be with the voice of the archangel and with the trump of God (1 Thess. 4:1616For the Lord himself shall descend from heaven with a shout, with the voice of the archangel, and with the trump of God: and the dead in Christ shall rise first: (1 Thessalonians 4:16)). The “last trump” will sound at the resurrection of the saints (1 Cor. 15:5252In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed. (1 Corinthians 15:52)). In the Roman army, when it was about to start, the trumpet sounded three times: at the first trumpet they pulled down their tents: at the second they put themselves in order; and when the last sounded they started.
In the judgments that are to fall upon the earth, as foretold in the Revelation, the Seven Seals introduce the Seven Trumpets: the first four fall upon the Roman earth, and refer to the state and circumstances of men; the latter three trumpets refer to the East, and fall upon the persons themselves. The Trumpets come in between the Seals and the Vials (Rev. 8:22And I saw the seven angels which stood before God; and to them were given seven trumpets. (Revelation 8:2)Rev. 9:1414Saying to the sixth angel which had the trumpet, Loose the four angels which are bound in the great river Euphrates. (Revelation 9:14)).

Strong’s Dictionary of Hebrew Words:

from 8628 (in the musical sense); a trumpet
KJV Usage: