So, as you're no doubt aware, we trumpeters can take advantage of a mute - a little doodad that fits into the bell of the trumpet to make what is normally an extremely in-your-face sound and mellows it out and quiets it, at the cost of greater backpressure for the player and requiring specific jazz music to sound -good-.
Do they make those for euphonia or baritones?
In Xanadu did Kubla Khan A stately pleasure-dome decree Where Alph, the sacred river, ran Through caverns measureless to man Down to a sunless sea