`THIS is going to be the most difficult interview of your life," a harassed-looking radio journalist hissed at me as I approached Nina Simone. "The most difficult by far." It was, I confess, an alarming moment. Miss Simone, who performs at the Albert Hall tonight, has earned and maintained huge popularity as a singer and pianist over four decades, but she has a daunting reputation. Among divas - a group of performers noted for their ability to be awkward - she stands alone in show-business legend. On a Richter temperament scale from one to 10, she is said to hit at least 50 from time to time. There have been times when she has walked off stage, or not appeared - as on a famous occasion at Ronnie Scott's Club - until one o'clock in the morning. At other times she has not turned up at all, or chewed off the audience's collective ear. At least one writer has suggested that she is especially tough on white male journalists writing for broadsheet newspapers. There are other incidents in the cuttings file - such as the news report a couple of years ago of her discharging buckshot across her hedge in response to noisy neighbours - which also tend to unsettle the would-be interviewer. It looked as if the radio journalist had a point. 

Actually, as it transpired, the interview wasn't difficult at all. Unusual, certainly, in some ways disconcerting, but I couldn't honestly say it was difficult. Nina Simone, it is true, has a presence for which "formidable" is a weak, inadequate word, and a manner calculated to rattle the timid. Her remarks tend to be brief, to the point, and delivered at triple forte volume in a declarative fashion as if she were addressing a sermon to a large church (one remembers that she comes from a line of preachers, 15 of whom were numbered in her mother's immediate family). But she answered my questions civilly, if not at great length, and even offered me a cup of tea. 

In fact, the conversation began with tea. Miss Simone ordered a large cup of African tea - which she strongly recommends - from her assistant, a young man with elaborate dreadlocks. She then proceeded to add a couple of heaped spoonfuls of cayenne pepper. She regards this fiery spice as extremely good for the health, and consumes large quantities of it as part of her daily routine. "Cayenne is good for everything. If you have heart failure and you eat raw cayenne, it rekindles the heart and makes it beat again. I eat just raw pepper if I can't get anything else." I said I must try it, and expressed a liking for hot curries. 

So far, we seemed to be in agreement. At that point, leaving the tea to cool, in terms of temperature at least, she wheeled in her chair and said, "SHOOT!" so I started asking questions. 

But where to begin? She was born Eunice Waymon in North Carolina 65 years ago (Nina Simone is a stage name, the "Nina" supplied by a Hispanic boyfriend, "Simone" from Simone Signoret, an actress she admired). An infant prodigy, Simone was playing the piano by ear at three and studied classical piano from the age of five. Her mother was a Methodist minister - and still is, she told me. "Ninety-six on November 20. GOOD GENES." 

As a performer, her repertoire is extremely eclectic - jazz, folk, blues, pop, classical, Jacques Brel, Bob Dylan, you name it - but the secret of her delivery has always seemed to me to lie in that background in the gospel church. She can muster the vocal majesty and electrifying force of a Southern preacher, or a singer such as Mahalia Jackson. But she has applied this vocal and spiritual power to all manner of songs (as did, once upon a time, Bessie Smith, another singer with a reputation for being difficult). 

The effect she wanted to produce on her audiences, she wrote in her autobiography, I Put a Spell on You, was "to make people feel on a deep level. It's difficult to describe because it's not something you can analyse; to get near what it's about you have to play it. And when you've caught it, when you've got the audience hooked, you always know because it's like electricity hanging in the air." 

So, I suggested, she wanted to work on the audience like a preacher on a congregation? "EX-ACT-LY. You got that right. Give them courage." As an answer, it could have been fuller, but we seemed to be on the right lines. The other element in her art, and her career, was her training as a classical pianist. This came to an abrupt halt when she was rejected by the Curtis Institute of Music in Philadelphia, a rebuff she has always attributed to racism. Does she still regret that she did not become a classical pianist? 

"I have never gotten over it, after all these years, although I'm more famous now than the Curtis Institute of Music, or Juilliard. Never. I play classical music in my room. It soothes me. Being a classical musician wouldn't be so hard, classical people know how to treat you. They know how to pull the red carpet out for you, they know how to rehearse, they know how to get it perfect." 

Here we get to the nub of why divas are difficult. It is very clear from her book that she bitterly resents the sheer, wearing grind of show business - the travelling, the messed-up arrangements, the battles over contracts, the emotional drain of turning on a thousand-watt performance night after night. And, you must admit, she has a point. Performers of her kind are artists, but the club and concert-hall treadmill is not an easy situation in which to create art. 

The other part of it is political. In the Sixties she lined up with militant black figures such as Stokely Carmichael and Malcolm X. And she has not mellowed on this point. I asked her whether she thought that things had improved for Afro-Americans since those days. "It's worse, they killed all our leaders except Louis Farrakhan. I don't go back to the States. I went this year and it was very hard and I'm not going back there any more." 

ON the other hand, she doesn't much like Europe, where she has been living for most of the past two decades. "Europe, I find, is like a graveyard. No one speaks, no one is friendly, no one talks, they ignore me completely. I don't find that true in Africa. Everyone's friendly, everybody's warm and intuitive." 

Africa, where she lived in the Seventies and where she recently returned to attend President Nelson Mandela's 80th birthday celebrations, is clearly her perfect place. But how about France, where she now lives? "In France they don't bother me, but they are not very friendly at all. The French are terrible. In England people are much more polite and enthusiastic than the French." On which flattering note, she took a large gulp of cayenne tea. "Woo," she remarked approvingly, "that's HOT." 

(Copyright 1998 (c) The Telegraph plc, London)