Bardic Blessing

You conjure a copy of your self playing the musical composition within range. Copy counts as an illusion and plays a melody or song that can be heard for 300 ft. Every creature that can hear the melody becomes influenced by it. If a target is friendly whenever it makes an attack roll or a saving throw before the spell ends, the target adds 1d4 to the attack roll or save, if a target is hostile It must succeed a saving throw of Charisma, on a fail whenever it makes an attack roll or a saving throw before the spell ends, the target subtract 1d4 from the attack roll or save

Using a Higher-Level Spell Slot. You can create one additional copy, for it each spell slot must be 2 higher than the previous one, effects from different copies stack, but each copy must use a different musical instrument.