He was an associate professor in the department of voice and opera at Temple's Boyer College of Music and Dance.
During summers since 2003, Mr. Douglas also had been head of the music staff, chorus master, and director of the apprentice program at the Lake George Opera in Saratoga Springs, N.Y.
Born in Morgantown, W. Va., Mr. Douglas graduated from Tates Creek High School in Lexington, Ky., in 1973, earned a bachelor's degree in music at Wittenberg University in Springfield, Ohio, in 1977, and a master's of music in piano performance at Bowling Green State University in 1979.
Mr. Douglas was an instructor of European diction in the voice department of the Boston Conservatory from 1980 to 1989. He had joined the New England Conservatory of Music in 1979 and headed the music staffs at both until 1989.
Besides his schoolwork, his summer assignments ranged widely.
In 1983 and 1989, he was assistant conductor of the Central City (Colo.) Opera Company.
In 1985 and 1986, he was an instructor and German diction and repertoire coach at the American Institute for Musical Studies in Graz, Austria.
From 1990 to 1993, he was music director of the Ash Lawn Opera Festival in Charlottesville, Va., and from 1996 to 2002, he was coach and teacher at the Chautauqua (N.Y.) Opera.
Mr. Douglas was also an accompanist over the years for, among others, Denyce Graves in a 2007 performance at Ohio State University.
His sister, Sara Douglas, wrote in biographical material that "in his 21 years at Temple, he conducted 50 productions of major operatic works from both the standard and contemporary repertoire."
Most recently at Temple, Mr. Douglas conducted Le Nozze di Figaro in 2009, La Boheme and Egisto in 2008, and Le Rossignol and L'enfant et les sortileges in 2007.
Since 2003, he had been a board member of the National Opera Association in Canyon, Texas. In 2006, he earned the Temple University Faculty Award for Creative Achievement.
Besides his sister, Mr. Douglas is survived by his wife of 33 years, Melissa; parents John and Marilyn Douglas; son Matthew; and daughter Willa Rose.
A life celebration took place at the Unitarian Society of Germantown on Sunday, July 18.
Contact staff writer Walter F. Naedele at 215-854-5607 or firstname.lastname@example.org.