Opus 76 for Duke University and Opus 76A for Westminster Choir College were built at the same time and are essentially identical. Slight differences include the Duke instrument's flat pedalboard, whereas the Westminster organ's pedalboard is concave and radiating. Due to its location in a smaller room, the Duke organ is voiced more softly than Westminster.

These two-manual and pedal instruments, used primarily for teaching, each have a white painted case with mahogany trim, keydesk, and pipe shades. There are three hook-down pedals, which activate the couplers. The front pipes are hammered and polished lead, the naturals keys are grenadil and the accidentals are bone-topped rosewood.