Numbers 10:10
Also in the day of your gladness, and in your solemn days, and in the beginnings of your months, you 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.
Torrey's Topical Textbook—AKJV

Psalm 81:3
Blow up the trumpet in the new moon, in the time appointed, on our solemn feast day.
Torrey's Topical Textbook—AKJV