Last week, maestro David Fanning and the National String Symphonia brought my piece, Retablos, to life for the first time at the Kennedy Center’s Terrace Theater. The piece features a fiendishly difficult percussion part that requires the percussionist to leap from the bass drum to the vibraphone, to various temple blocks, and back to ten other instruments. For the soloist, Mark Carson, it was an exercise in choreography and stamina as much as it was in musicality. Mark and I (but mostly Mark) worked off and on for months to make sure that this percussion part was playable. The result was a fluid and, honestly, gorgeous performance. The NSS will perform it again in Baltimore on March 11.