In this case, it’s the Shades of Leonard Cohen’s musicians, the way past cool Roscoe Beck (Musical Director and Bass) and Rafael Bernardo Gayol (Drums and Percussion), shown here at the Wiesbaden concert in a photo by N Kloeppel. (Thanks to Christine for finding this shot)

Same concert, different musicians behind those sunglasses - see Shades of Leonard Cohen #23 - Javier & Dino

A gallery comprising all items previously published in the photo series, Shades of Leonard Cohen, can be viewed at Collected Shades Of Leonard Cohen.