Karl has held bass trombone positions with the Calgary Philharmonic Orchestra, New World Symphony, Colorado Springs Symphony Orchestra, and he has performed as a substitute with the Baltimore Symphony Orchestra.  Karl's doubling experience includes work on euphonium, tenor trombone, contrabass trombone and bass trumpet with ensembles including the Wolf Trap Opera, New World Symphony, and National Gallery Orchestra.  Karl has enjoyed performing under many notable conductors including Michael Tilson Thomas, Franz Welser-Möst and Osmo Vänskä. He has also recorded for television, and performed popular music with luminaries including Idina Menzel.

While earning his Doctor of Musical Arts degree from the University of Maryland, Karl became an avid marathoner, ultramarathoner, and Ironman Triathlete.  He believes that mental and physical challenges–both artistic and athletic–can help shape us into mindful citizens who make unique contributions through healthy self-expression.