Roman tuba

[3][4][5] They would signal troop movements such as retreating,[6] attacking, or charging,[7][8] as well as when guards should mount, sleep,[9] or change posts.

[7][10] Thirty-six or thirty-eight tubicines (tuba players; singular tubicen) were assigned to each Roman legion.

[11][12] The tuba would be blown twice each spring in military, governmental, or religious functions.

[2][5][19][20] They were typically made of metals such as silver,[21] bronze, or lead and measured around 4.33 ft or 1.31 meters.

[27] Ancient writers describe the tuba as invoking fear and terror in those who heard it.