I've just been standing on Millenium Bridge, listening to this brass band. I can still hear them as I write, in fact, as the kitchen door is open and the notes are drifting across on the breeze. This event takes place every year apparently and is called "Praise on the Bridge," organised by York Churches Together. It's a half hour service, constisting mainly of favourite, traditional hymns.
I've missed seeing brass bands around the place.