עֲשֵׂ֣ה לְךָ֗ שְׁתֵּי֙ חֲצֽוֹצְרֹ֣ת כֶּ֔סֶף מִקְשָׁ֖ה תַּעֲשֶׂ֣ה אֹתָ֑ם וְהָי֤וּ לְךָ֙ לְמִקְרָ֣א הָֽעֵדָ֔ה וּלְמַסַּ֖ע אֶת־הַֽמַּחֲנֽוֹת׃
’Make thee two trumpets of silver; of beaten work shalt thou make them; and they shall be unto thee for the calling of the congregation, and for causing the camps to set forward.
Read kabbalistic (mystical) interpretation of Numbers 10:2: and classical mystical sources.