Music in Paris

 I'm in Paris at the moment, came up on the Eurostar this afternoon.

I'm staying in the same hotel I stayed in the last two times I visited Paris, near the Gare de Lyon.  I went out for a meal and when I got back there appeared to be a crowd gathered outside my hotel, and somebody addressing them with a microphone.  They were actually outside the bar next door and what was immediately obvious was three large sousaphones being carried.  A closer look and I noticed other brass instruments.

The receptionist in the hotel had no idea what's going on, but they are currently playing music outside my window.