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There are two quite different instruments translated as trumpet or trumpets. The 'Sopar', or 'Sophar', a ram's horn, is translated trumpet (singular), except for in Joshua and Judges. It is not really a musical instrument. It sounds only the second and third harmonic. It was used for signaling in battle and in the Temple. The 'sophar' is mentioned 72 times in the OT. You can view the references here.
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Trumpets (Kasoserah)
The 'kasoserah' was a straight metal bugle about two feet long. It was always used in pairs, if not more. It is translated trumpets (plural). The 'kasoserah' has 29 references.
In the New Testament, only one Greek word 'salpinx' is translated trumpet, always the singular. Was this a 'sophar' or a 'kasoserah'? In the NT, 'Salpinx' and the verb form 'salpizo' are mentioned 23 times. A few key verses are:
The Lord said to Moses: "Make two trumpets (kasoserah) of hammered silver, and use them for calling the community together and for having the camps set out." Num 10:1-2
So all Israel brought up the ark of the covenant of the Lord with shouts, with the sounding of rams' horns (Shophar) and trumpets (kasoserah), and of cymbals, and the playing of lyres and harps. I Chr 15:28.
Picture Credit: The Interpreter's Dictionary of the Bible, Vol. 3, ** p 473, plate 88; * page 472, plate 85; *** page 473, plate 87, Abington Press.
Created 9/14/97, Last Revised 09/08/01