At the beginning of the semester, Professor Manning gave me a link to the group the Brass Liberation Orchestra. This brass group is on the go in a few different ways. They go to places and move around while they play. The main thing, however, is that the BLO uses their music to support their views on various subjects. They are using their brass playing to start a movement. The pieces they play are specifically chosen because of the meaning of the lyrics or the context in which they were composed. On their website, you can find recordings and sheet music. You can also read the BLO's views on gentrification and immigrant rights.
Here is a video from an event where they participated