A.R.T.: Debut. Walt Bostian, trombone, has played the national tours of The Lion King, Wicked, and other shows during their Boston runs. In addition he has performed with the Boston Ballet, Boston Modern Orchestra Project, The Rhode Island Philharmonic, and The Portland Symphony Orchestra, as well as touring with Bim Skala Bim and Roomful of Blues. He is an Honors graduate of the New England Conservatory.