"You do know it's only a guest spot, don't you?" her own press officer stresses. Some of Irish music's greatest names are taking part in the "From the Heart" series of concerts which started on Thursday and ends on 17 April, among them Mary Black, who outsells everybody but U2 in her native country, and Sharon Shannon, "who is to the accordion what Jimi Hendrix was to the guitar". But, as usual, it will be O'Connor who makes the headlines.
Estimable as the others are, none of them ever made a single that was No 1 in 17 countries, as O'Connor did with "Nothing Compares 2 U". None of them ever tore up a picture of the Pope live on American television, or endured a tabloid feeding frenzy to match the one provoked by the young Sinead's support for the IRA (since withdrawn). Neither did they speak openly about being abused as a child.
It has been an extraordinary life, chronicled in detail. The woman the Sun called a "she-devil" for her views on the Gulf War has also had to read lurid accounts of her own nervous breakdown and suicide attempts, not to mention several miscarriages and at least one abortion. Yet she seems to have achieved a measure of stability after making the decision to drop out of public life in 1995. Since then Sinead has lived quietly in west London with her 10-year-old son Jake and his sister Roisin, born just over a year ago. She enrolled to study theology at a local college, but found it "too tricky" to combine with motherhood and music. She stopped giving interviews, except for one in October to promote the Childwatch campaign. "Two years ago I was in a major depression," she said at the time. "I feel safer now."
Safe enough to release a four-track EP later this month, and return tentatively return to live performance as a guest of Donal Lunny, the virtuoso musician and producer known as the Quincy Jones of Ireland. Lunny first worked with O'Connor in 1991 on "My Special Child", a single she recorded in aid of Kurdish refugees. He has also produced and appeared on records by Kate Bush, Elvis Costello and Rod Stewart, among many others, and was a member of the seminal Irish bands Planxty and Moving Hearts, who revolutionised traditional music in their country by applying rock sensibilities to dance tunes and ballads.
Lunny, the musical director of "From the Heart", sees Sinead as a key figure in the regeneration of Irish music. "She is somebody that young Irish people can relate to. You must reinvent, restructure what the music is, and what the art is, to each succeeding generation."
Her emotionally direct interpretation of the ballad "On Raglan Road" was a highlight of Common Ground, a compilation of new recordings inspired by traditional music that Lunny made last year. She sang it with him in Belfast in February, and may do so again this week. Despite her reputation as a troubled soul, Lunny says O'Connor is easy to work with. "She is quite determined - she will follow her own path - but I find her extremely agreeable."
O'Connor has chosen to make her comeback in an intimate setting, very different from the stadia she once filled. She will be among friends; Lunny and his musicians are veterans of the traditional circuit, impressed more by talent than tabloid infamy. Her new recordings make more use of traditional instruments than before, and Lunny believes her work "taps into the same emotional centre" as the oldest Irish music. "Sinead is an exquisite singer. Any chance I get to say it, I will. Her talent as a singer has been overshadowed by the media frenzy that has accompanied some of her ... statements. But I would say that she is one of the big singers, a performer who can bring a tear to your eye, and put a chill down the back of your neck."
Tears changed Sinead O'Connor's life. Her first album, The Lion And The Cobra, established her as a cult figure, a wailing banshee notable for her savage skinhead crop. Her second, I Do Not Want What I Haven't Got, included in "Nothing Compares 2 U" a version of one of Prince's lesser- known songs. She made an ordinary ballad sound like a confessional, and had a huge hit. But it was the video that really grabbed attention. In the middle of the song, with the camera up close to her face, O'Connor began to cry. The tears seemed real. They were real, according to rumour. Was this some private grief from which our eyes should be turned away? Were we being manipulated? It was an uncomfortable moment: O'Connor had blurred the boundaries between the public and the personal, a confusion that would define her career.
Alerted to the girl they called "Bambi in bovver boots", the tabloids didn't have to look far for a story. She had already told the music press about her early days as a waitress, a kissogram girl and, most graphically, as a victim of child abuse. "I thought they [the journalists] were really interested and were going to help, so I began exposing myself in stupid ways," she said later.
They discovered that she was the daughter of a barrister, and had been born in December 1967. Sean and Marie O'Connor separated in 1975, when their daughter was eight years old, although divorce was then illegal in Ireland. He became a prominent campaigner for a change of the law, and she took refuge in religion, drink and tranquillisers.
A court broke with Irish custom and granted custody of the children to Sean, but Sinead begged to go back to her mother. She was rewarded with five more years of what she now says was torture: sexual and psychological abuse, and the periodic withdrawal of light, heat and clothes. "I was made to kneel on the floor and open my legs while my mother spat on my vagina and kicked me in my womb," she told Esther Rantzen on last year's Childwatch programme. "We were locked in our rooms and not fed ... the usual neglect stuff."
Having run back to her father at 13, O'Connor was sent to a college for girls with behavioural problems, and then to a more liberal, Quaker- run school. Neither could help her deal with the anger she felt inside, which was expressed instead through song. She quit school before taking her leaving certificate to sing with a band called Ton Ton Macoute, but record company scouts were only interested in the singer. So O'Connor moved to London in 1985 with her drummer and partner John Reynolds, and signed to Ensign Records. It was also the year her mother died in a car crash, leaving her "without any answers". Their son Jake was born in July 1987, and she married John soon afterwards; they are now divorced, but remain friends and musical collaborators.
Her internal struggles were exacerbated by fame. She boycotted awards ceremonies in protest at the Gulf War. There was the incident with the photograph of the Pope (His Holiness being a symbol of all that had created her mother and taken the Irish people away from God). She bought a house in Los Angeles, and then gave it away to the Red Cross after suffering "some sort of a breakdown". By the end of 1992 she had announced her retirement and moved back to Dublin, despite the success of her third album, Am I Not Your Girl, a collection of cover songs from her chidhood.
In 1993 she published a long poem in the Irish Times about her abuse as a child. Her brother Joseph, a novelist, responded by stressing that his father and other members of the family had offered as much support as they could. "For some time now I have been at a loss to square the public version of the life of our family with the facts as I know them," he said. He later suggested that his sister exaggerated her troubles. Her sister Eimear told Hello! that she had dealt with the same demons in private. "I don't dwell on the past."
O'Connor's usual themes of abuse, motherhood and the betrayal of the Irish people by Britain and the Catholic church were present in her fourth album, Universal Mother, but her performance was more controlled than ever, and the lyrics showed Sinead's growing fascination with pre-Christian spirituality and the concept of God as mother.
In 1995 she was interviewed for the Irish Times by a feature writer called John Waters. He understood that talking about her family history had been an essential part of her work. Her hair was growing out, and she told him that her shaved head had been a subliminal signal. "My sister told me for years, and I scoffed at it, that it was to do with sexual abuse. That I wasn't comfortable with my womanhood. I hardly ever wore dresses, or if I did I wore trousers underneath. I was uncomfortable when anyone was sexually attracted to me. Or when I was attracted to anyone else."
Such as her interviewer, for example. O'Connor found Waters "a beautiful human being", and by the end of the year she was pregnant with his child. She later admitted having "targeted" the 40-year-old as a potential father, and said that they were not a couple. In an article for the Irish Times last month, Waters wrote that men were being forced to find new expressions of fatherhood; Roisin's mother and he remained "on good terms" which meant he saw his daughter often.
As usual, O'Connor's attitude was attacked by the more conservative elements of the Irish press. Ireland is changing, and the legalisation of divorce in February showed the grip of church on society loosening. Those who resent such change see O'Connor as a symptom of all that is wrong. Others see her sustained assault on the oppressive Catholicism of her childhood as prophetic. They admire her for having questioned Ireland while retaining an identifiably Irish voice. Huge record sales can't be ignored, and the Irish Tourist Board has taken a pragmatic approach: its 'Rock 'n' Stroll' tour of places in Dublin where the greats of Irish music started out now includes the Bad Ass Cafe, a burger restaurant in Temple Bar where O'Connor once waited tables.
The new record is called Gospel Oak. Aside from being a railway station in north London, the name has spiritual connotations. "She feels the songs are like hymns or lullabies," said her press officer. "They are dedicated to the idea of God before 'religion' came along, and to the concept of God as the mother, which was symbolised in ancient times by the oak."
Her voice is more haunting than ever on the first track, "To Mother You". Listening to it, my eye fell on something she said to John Waters. "Those of us who have a voice are crying the grief on behalf of those who are afraid to cry it," she said, aligning herself with the ancient Irish custom of keening, in which certain women were invited to cry out the pain of mourners at a funeral, in wailing song. "Keeners were people who were always considered to be crazy, who lived on the outskirts of society. People were frightened by them." !