Revelation 8:6

So the seven angels who had the seven trumpets prepared themselves to sound.

Leviticus 23:24 Speak to the children of Israel, saying:  in the seventh month, on the first day of the month, you shall have a Sabbath-rest, a memorial of blowing of trumpets, a holy convocation.

Hebrews 12:19  and the sound of a trumpet and the voice of words, so that those who heard it begged that the word should not be spoken to them anymore