William Warfield: When the spirit is willing

When the standing ovation for the bass-baritone William Warfield finally dies down in Sanders Hall, Harvard, the audience's hearts have all but been wrung out. The Boston Philharmonic Orchestra programme includes Aaron Copland and Joseph Schwantner's setting of Martin Luther King Jr texts, New Morning for the World (Daybreak of Freedom). One of their sold-out Bose Discovery Concerts, the theme is "The search for the possibility of a better world".

In terms of possibility, Warfield, now 82, is a triumphant example of the human spirit's refusal to be diminished by the physical challenges of old age. "Music will always be a healing refuge," he says, "a refuge to which man retreats whenever he needs something beyond himself."

Warfield's interpretation of Old American Songs leaves the audience in no doubt as to what Copland's folk-song arrangements must have sounded like when this charismatic son of a Baptist minister first sang them over 50 years ago. For an encore, he turned to "Ol' Man River" – a song with which he has a long association. In Warfield's voice, that most poignant phrase, "I'm tired of living and scared of dying'", sounds frighteningly honest.

A professor at Northwestern University since 1994 and chairman of the Illinois Voice Department, Warfield also tours with the Jim Cullum Jazz Band as narrator in their concert presentations of Porgy and Bess, Showboat and Harlem Rhapsody. When I ask him why he can still be bothered to jump on a plane to sing somewhere, instead of sitting in an armchair at home in Chicago, he tells me a story. He sets the scene in a melting voice of perfect clarity. "When I reached 60 and was professor of music at the University of Illinois, I sort of half retired from singing, thinking maybe the time had come for me to give it up completely and just do masterclasses. One night, lying in bed, something came over me that I still can't quite describe. I guess it must have been a message from God. What I heard was this. 'I gave you that voice. I'll tell you when to quit.' I thought I'd better listen. And you know something? Singing still continues to fill my life with joy. If it didn't, I wouldn't be doing it."

Listening to the man who won a Grammy in the Spoken Word category for his narration of Aaron Copeland's Lincoln Portrait, I feel as if I'm sitting in church, captivated by a great preacher. William Warfield has that effect on a lot of people. For decades, critics have commented that his superiority as a recitalist stems from his unusual ability as an actor. "Singers," he modestly suggests, "unlike other musicians, are very lucky. Beauty by itself isn't enough to touch people. You also need ideas and emotions. For that, we have words to work with – the poetry of Schiller, Heine and so many others." Tonight, that poetry includes some of Martin Luther King's most resonant phrases, which Warfield delivers in a profoundly moving dramatic narration. The pianist Kevin Cole, another regular guest artist with the Boston PO, says afterwards, "When I leave this earth, I hope I'm fortunate enough to meet my creator, and that he sounds like William Warfield."

Born into a family of Arkansas sharecroppers, Warfield is an American musical legend. One of the foremost interpreters of the role of Porgy in Gershwin's Porgy and Bess, he has sung everything from grand opera to Broadway shows, and is one of the first African-American male singers to make an international career in classical music. His passion, though, has always been German lieder and their US counterpart, the African-American spiritual. "I was introduced to the spiritual in my father's church. I grew up with it. For me, the spiritual is as necessary as eating and sleeping. I've been singing Schubert since high school. In my fifties, things came out in Schubert's songs that never occurred to me at 30. Now, if I sing Die Schöne Müllerin or Winterreise, other things come to me – to do with the experiences of life. Singing is an opportunity to share those experiences with others."

Warfield's career has taken him around the globe several times. He hasn't sung in the UK since 1974 (when he narrated Aaron Copland's Lincoln Portrait with the New York Philharmonic and Leonard Bernstein). When the Boston Philharmonic's conductor, Benjamin Zander, was invited to conduct an all-American programme with the Philharmonia Orchestra at Birmingham's Symphony Hall this month, he wondered if Warfield, with whom he had worked many times, would consider crossing the Atlantic one more time. "Well, yes, I would," came the reply. "But I don't think it's going to be possible. I'm very busy." Warfield had a long-standing concert engagement in Atlanta over the Independence Day weekend. "But," he smiled, "perhaps I might ask them to reschedule."

Atlanta was happy to oblige, so Zander got his dream team for Symphony Hall – William Warfield and the Chicago-based pianist Kevin Cole. In 1996 and 1997, Cole was piano soloist for the Boston Philharmonic's Gershwin tribute concerts. "I'm of the William Warfield school, which is all about struggle, possibility and joy in music. That's why we both love working with Ben and the BPO. For most soloists, there are three concert landscapes – Conductor Land, Soloist Land and Orchestra Land. Somewhere you have to come to a peace agreement. With Ben, all those territorial lines are wiped away. It's total collaboration."

For his UK debut, Cole promises that audiences in Birmingham will hear a very different performance of Rhapsody in Blue to the "German Romantic" style most of us are used to. "Gershwin should crackle, caress and shock."

Cole, 43, grew up in Bay City, Michigan. Gershwin has been a theme running through his life since he saw the movie Rhapsody in Blue on TV when he was seven years old. "I wanted to know more. The local librarian gave me Edward Jablonski's The Gershwin Years. Ed was from my home town. I promised myself that one day I'd go to New York and meet him." At 15, in New York for the first time, Cole looked him up in the telephone book, explained that he was mad about Gershwin and was invited for dinner to his apartment. "Ed asked me to play something. I'd never actually heard Gershwin play but I knew 'Embraceable You', 'I Got Rhythm' and a couple of preludes. When I'd finished he put on some tapes of Gershwin radio broadcasts, saying, 'Doesn't he sound familiar?'"

Jablonski asked Cole to play for the lyricist EY Harburg, a boyhood friend of the Gershwins, who told him that he'd never heard anyone play piano like that since George. Harold Arlen and Irving Berlin were also astonished when they listened to Cole. "Maybe my style of playing is more akin to the styles of the day. It's always best to go to the source or the people who knew them well, because there's an unspoken emotional connection that is transferred to you."

Jablonski says simply, "Kevin is the best Gershwin pianist since Gershwin himself – no one can touch him." Which is why Benjamin Zander is so excited about bringing him to the UK. "Sometimes, when Kevin starts to play, you would swear it was George Gershwin at the keyboard. You can't teach anybody to play that way – they just do it."

The Philharmonia Orchestra's American concert is at Birmingham Symphony Hall tomorrow at 8pm (0121-780 3333)