He later studied with Michael Chertock of the Cincinnati Symphony Orchestra and participated in master classes by George Crumb, Seymour Lipkin, Emanuel Ax and James Tocco.
[9] Their latest one-act opera, The Ghosts of Gatsby was commissioned by Samford University under the direction of Kristin Kenning.
Currently, Mack & McGuire and director Christopher Mirto are composing a musical comedy called, The World Still Needs You, Boris Yeltsin!
Mack's choral suite, Langston Hughes’ Dream of Freedom was a Selection Winner of the National Association of Composers, San Francisco and the UCM New Music Festival.
Mack's work for two pianos, American Groove, was performed by the Westhuizen Duo across the United States and South Africa throughout 2011.