Mute alters the sound of a trumpet (and other brass instruments as well) in a very interesting way. The sound it produces is both pleasant & pretty nasty. It stings like a bee that feels really nice in your chest.
Of course mutes also damp the sound, hence the word “mute”.
Brass instruments without mutes might as well be called “deafs”, ‘cos they are loud! You wouldn’t wanna share a prison cell with a guy who practices trumpet with a passion (and who is also doing time for an assault with a deadly labrophone).
So, today we got jazz with strings & a vibraphone and it’s mellotron buddy, starring muted trumpet: NO FLAX.