Richard Flanagan (pictured) is a substitute percussionist in the Boston Symphony. (He is a number of other things as well, as several thousand online entries for his name attest.) He's at Tanglewood whenever a piece on the concert program has huge festive orchestration, with triangle or gong or wind machine or drum set or slide whistle. In other words, when there's a musical party.
I have appointed myself his groupie, and when I can, I wave to him or hasten up with a breathless greeting. Pleasantly tolerant, he assures me that he's never had a groupie, and I assure him that there's no telling how many listeners I might represent, sitting blandly till a sparkling sound or crash or thud brings their eyes to stage left -- or stage rear -- to check what gave that hollow volume or crisp definition to the big cadence.
Flanagan's name doesn't appear on the list of orchestra members, but he gives essential spice to numerous classical and maybe all Pops concerts. Take a look for him the next time a concert moment turns into a musical party.