The Roman Legions employed a number of trumpeters called 'tubae' and played by selected soldier/ musicians to signal particular troop movements in battle such as 'advance, attack and retreat' as well as at different times when guards in camp should mount, sleep or change posts.
36-38 'Tubicenes' (soldier/players) would be assigned to each Legion.
These early military musicians would also take part in the 'Triumphs' with some or indeed all of the Legion's complement marching in the parade on those days.
Here are our set of 4.