The final judging for the £30,000 Orange Prize for Fiction starts on Monday.
There were no votes at stake but the authors met the reading public for a sort of literary hustings on the final day of the Hay Festival on Sunday.
The 10th award, for women authors only, will be presented on Tuesday night.
Half the six shortlisted authors this year are American, the others include a writer from Yorkshire who rode with an "outlaw biker gang" in the 1970s.
The judging panel chaired by broadcaster Jenni Murray, including comedienne Jo Brand and newsreader Moira Stuart, waded through 120 novels to reach this point.
Murray admitted the task would be "extremely difficult".
Joolz Denby's Billie Morgan is a long way from an 'aga saga,' drawing on her own experiences of a biker gang. She also has years as a punk poet and has attracted attention for her collection of tattoos.
"It's a novel about the dark power of secrets," said the 49-year-old, set in her home Bradford, "one of the most beautiful cities in the country... people don't think that".
Old Filth is a "book full of horrors," says Jane Gardam, who is in her 70s and has won the Whitbread Novel of the Year award twice.
Set in the Far East, it tells from birth to death, the story of lawyer Eddie Feathers. He never knows his mother, and later suffers everything from venereal disease to breakdown.
Sheri Holman's The Mammoth Cheese is set in rural America and the media circus surrounding a woman who gives birth to 11 children.
Holman, who learnt how to milk a cow to help her with the detail of farming practises in her book, found life imitating art - she had twins after writing the novel. She said: "My husband says my next novel must be about winning the lottery."
Marina Lewycka's reading from A Short History of Tractors in Ukrainian brought widespread laughter from the Hay audience.
Her debut novel relates the family tensions as an 84-year-old widower marries a much younger woman "with superior Botticelli breasts", who arrives from his native Ukraine in search of a passport.
The shortlisted authors signed their books at Hay on Sunday
Lewycka, now a lecturer in Sheffield, was born in a German refugee camp to Ukrainian parents.
Maile Meloy's Liars And Saints is another first novel (originally started as two short stories) on events leading from a chance meeting with a photographer while her husband is at war in Korea.
"It's about the secrets we keep from each other and how that pans out over 60 years" said the California-based writer.
We Need To Talk About Kevin by Lionel Shriver was written "before high school shooting books became a genre." It is the voice of a mother as she tries to understand why her son killed seven fellow pupils, a teacher and canteen worker.
Lionel explained that her name change at 15 was to lose 'Margaret-Ann'. "I wanted to be a boy, but I have to add - it didn't work".
Andrea Levy won last year's prize for Small Island, which became a best seller. Past winners include Carol Shields and Helen Dunmore.