'Trumpet' in the Bible

I was in the Spirit on the Lord's-day, and I heard behind me a great voice, as of a trumpet, saying,

After these things I saw, and lo, a door opened in the heaven, and the first voice that I heard is as of a trumpet speaking with me, saying, 'Come up hither, and I will shew thee what it behoveth to come to pass after these things;'

And I saw, and I heard one messenger, flying in the mid-heaven, saying with a great voice, 'Woe, woe, woe, to those dwelling upon the land from the rest of the voices of the trumpet of the three messengers who are about to sound.'

saying to the sixth messenger who had the trumpet, 'Loose the four messengers who are bound at the great river Euphrates;'