Voice teachers

Florence Gillam Birdwell (September 3, 1924 – February 15, 2021), sometimes referred to as Flo Birdwell, was an American educator, musician, and singer. She taught musical theater and opera singing for more than six decades. She served as a professor of voice at the Bass School of Music at Oklahoma City University from 1946 to 2013, and afterwards periodically teaching master classes as a professor emerita.
In 2024, the National Association of Teachers of Singers honored Birdwell's career and contributions by naming the first prize of its annual National Musical Theatre Competition "The Florence Birdwell Award." The competition, held in New York City and featuring O'Hara as honorary host, took place on Jan. 8, 2024.

Mac Morgan (June 25, 1917 – June 12, 2007) was an American bass-baritone who had an active performance career in concerts and operas from the early 1940s until the mid-1970s. The Boston Globe described him as a singer "known for his rich tone and enviable diction". After retiring from the stage, he embarked on a second successful career as a voice teacher.

Hertha Töpper (German: ['hɛrta 'tœpər]; 19 April 1924 – 28 March 2020) was an Austrian contralto in opera and concert, and an academic voice teacher. A member of the Bavarian State Opera, she appeared in leading roles at major international opera houses and festivals.

Benita Valente (born October 19, 1934) is an American soprano whose career has encompassed the operatic stage as well as performance of lieder, chamber music and oratorio. She is especially lauded for her interpretations of Mozart and Handel, but she also excelled in certain Verdi roles. The New York Times once referred to her as "as gifted a singer as we have today, worldwide."