[1][2] Playing the Crystal Cathedral organ on the weekly Hour of Power television program, he was seen by an estimated audience of twenty million viewers in 165 countries.

[1][3] Swann lived in Palm Desert, California, where he was Artist-in-residence at St. Margaret's Episcopal Church from 2001 until his death in 2022.

His oldest brother, Edgar, an organist and ordained clergyman, was killed in a glider accident while serving as a World War II Army chaplain on February 19, 1944, and is buried at Arlington National Cemetery.

[5][6][7] Swann began taking piano lessons as a 5-year old from the organist at Market Street Methodist Church in Winchester, Virginia.

[5] When he was ten years old, the organist at Braddock Street Methodist Church in Winchester, where his father was pastor (1937–1943), died suddenly.

[3][8] Madeline W. Riley, the church's Minister of Music, was of significant influence in helping him develop the service playing skills for which he has become so well known.

[9] He chose the college on the shores of Lake Michigan, he would say years later, because "... my childhood was not the happiest, and at that point in my life, the farthest place away that I had heard of was Chicago.

[9][11] Swann was associated with the music ministry of the famed Riverside Church in New York City from 1952 through 1982, first as a substitute organist for Virgil Fox and then appointed Organist in 1957, when Fox's appearances at Riverside became infrequent until his departure in 1965 to pursue a full-time career as a concert performer.

[15] He directed the 75-voice paid choir from the organ bench for Sunday services and oratorios, such as Ralph Vaughan Williams's Hodie and Stabat Mater by Polish composer Karol Szymanowski.

[15] Beginning in June 1982, Swann was appointed Director of Music and Organist at the Crystal Cathedral (now Christ Cathedral) in Garden Grove, California, where he conducted the choir and presided over the 5-manual, 265-rank Hazel Wright organ of 16,000 pipes, appearing weekly on the internationally televised Hour of Power worship services.

[16] Swann told the Los Angeles Times years later that he was initially criticized in some professional organist quarters for leaving the prestigious, Gothic cathedral-like Riverside Church in New York for the Crystal Cathedral, saying he was "practically blackballed", but that he felt quite comfortable with his decision and found the Christian theology at both churches differing only in emphasis.

[18] At age 85 in 2016, Swann announced his retirement as a concert organist with a series of programs beginning in August of that year at the Kotzschmar Organ in Portland, Maine.

His performance was praised by music critic Allan Kozinn of the Portland Press Herald as possessing a "commanding sense of pace and color".

[25] At the AGO's July 2010, national convention in Washington, D.C., Swann was presented with the Edward A. Hansen Leadership Award by the organization's vice president, John Walker.

[28][29] In receiving the award, conferred biennially for outstanding leadership, Swann said to the thousands of delegates in the audience: "I am also grateful beyond expression for the friendship and support of a veritable host of AGO members over the years.

[16] The New York Times said his performance at a Riverside Church recital in 2006, "demonstrated that organists are complete athletes, needing both lightning-fast fingers and the fleet footwork of a dancer".

[33] In 2019, George C. Baker composed Berceuse sur le nom de SWANN, an organ work honoring its namesake.

[2] Of his choral anthems, composed while he was at the Crystal Cathedral, he said they were written "because I couldn’t find what I wanted to fit with the service of the day or they were not the right length.

They all had to be written in major keys, had to be loud, and had to end with the sopranos on high C, so there isn’t a great deal of variety.