At his most active as a pianist in the 1920s and 1930s, Seitz also accompanied Arthur Blight, Ferdinand Fillion, and Luigi von Kunits and was a member of the Five Piano Ensemble. He made his New York recital debut 4 Dec 1922, having performed there in April of that year as a soloist with the Toronto Mendelssohn Choir. Other US engagements included those with the New York Philharmonic, the Boston SO, and the Philadelphia Orchestra. He also performed twice (1922, 1924) in Toronto with the New York SO. After a Seitz recital, Hector Charlesworth wrote (Globe and Mail, 6 Nov 1942): 'Mr. Seitz in technical equipment and musical inspiration ranks among the foremost contemporary pianists... As an interpreter [he] has dignity and authority that arouse the confidence and expectation of listeners... His touch combines both tenderness and nobility, and is unique in its variety of emotional colour... Especially in Liszt numbers, he revealed a superb quality with the left hand that sets him apart from most pianists, but he unites with this asset a beautiful balance of style.'
Seitz taught 1916-46 at the TCM, where his pupils included Naomi Adaskin, André Asselin, Ewart Bartley, Muriel Gidley, Reginald Godden, Scott Malcolm, Adelmo Melecci, Earle Moss, Harold Packer, Charles Peaker, and Lorne Watson. Despite his prominence as a concert pianist and his success as a teacher, Seitz was known best as the composer of the melody of the 1918 ballad 'The World Is Waiting for the Sunrise' (words by Gene Lockhart). Other Seitz songs included 'Laddie Boy' (1932), 'When Moonbeams Softly Fall' (1935; words by Donald Heins), and 'The Sky's the Limit' (1943; words by G.L. Creed). Seitz retired from performance in 1945 and became president of the family business, an automobile dealership in Toronto. In 1984 Ernest Seitz Park was opened in Toronto.
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Author Marjorie Hale, Patricia Wardrop
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Hunter, Carl. 'Conservatory portrait gallery no. 2 - Mr. Ernest Seitz,' CQR, vol 10, Winter 1928
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Hutton, Jack. The World is Waiting for the Sunrise: An Affectionate Tribute to the Two Young Canadians Who Wrote the Tune in 1916, Ernest Seitz and Gene Lockhart (Bala 2000)