Question: Which British theatrical producer that appeared on the BBC's The Sound of Musicals, was considered  "the most successful, influential and powerful theatrical producer in the world" by the "New York Times?
Context: Kenny Wax is a British theatrical producer of musicals, plays, concerts and family entertainment. Adolph Klauber (29 April 1879 − 7 December 1933) was an American drama critic and theatrical producer.  He was born in Louisville, Kentucky to Edward and Caroline Brahms Klauber.  He left Louisville after high school to attend the University of Virginia, after which he moved to New York and took a position with the Empire Theatre Company.  In 1900 he began working as a reporter for the New York Commercial Advertiser.  From there he moved to the New York Tribune, and thence to the New York Times, where he became drama critic in 1906, a post he held for twelve years.  It was during this time that he married the actress and playwright Jane Cowl He then began working with Archibald and Edgar Selwyn, two of the founders of Goldwyn Pictures, later to become part of MGM, and worked for a while there as a casting director. Henry Moncrieff Tennent (18 February 1879 – 10 June 1941), commonly known as H.M. Tennent or Harry Tennent, was a British theatrical producer, impresario and songwriter.  From 1929 to 1933 he mentored Binkie Beaumont, having previously worked with him in Cardiff.  When Tennent, already the general manager at the Theatre Royal, Drury Lane, and assistant managing director of Moss Empires, persuaded the boards of Moss Empires and of Howard & Wyndham to amalgamate, in order the better to produce serious theatre, it was Tennent and Beaumont who became the new company's two chief executives. Herman Shumlin (December 6, 1898, Atwood, Colorado – June 4, 1979, New York City) was a prolific Broadway theatrical director and theatrical producer beginning in 1927 with the play "Celebrity" and continuing through 1974 with a short run of "As You Like It", notably with an all male cast.  He was also the director of two movies, including "Watch on the Rhine" (1943), which he first directed and produced on Broadway in 1941. Joseph "Joe" Papp (June 22, 1921 – October 31, 1991) was an American theatrical producer and director.  He established The Public Theater in what had been the Astor Library Building in lower Manhattan.  There, Papp created a year-round producing home to focus on new plays and musicals.  Among numerous examples of these were the works of David Rabe, Ntozake Shange's "For Colored Girls Who Have Considered Suicide When the Rainbow Is Enuf", Charles Gordone's "No Place to Be Somebody" (the first off-Broadway play to win the Pulitzer Prize), and Papp's production of Michael Bennett's Pulitzer Prize–winning musical, "A Chorus Line".  Papp also founded Shakespeare in the Park, helped to develop other off-Broadway theatres and worked to preserve the historic Broadway Theatre District. Sir Cameron Anthony Mackintosh (born 17 October 1946) is a British theatrical producer notable for his association with many commercially successful musicals.  At the height of his success in 1990, he was described as being "the most successful, influential and powerful theatrical producer in the world" by the "New York Times".  He is the producer of shows such as "Les Misérables", "The Phantom of the Opera", "Mary Poppins", "Oliver! ", "Miss Saigon" and "Cats. James Cundall is a British theatrical producer notable for his association with many commercially successful musicals and theatrical shows.  He is a founder of The Imperial Ice Stars and conceived York's annual Christmas ice-rink The Ice Factor. Eulalie Spence (June 11, 1894 – March 7, 1981) was a black writer, teacher, director, actress and playwright from the British West Indies.  She was an influential member of the Harlem Renaissance, writing fourteen plays, at least five of which were published.  Spence, who described herself as a "folk dramatist" who made plays for fun and entertainment, was considered one of the most experienced female playwrights before the 1950s, and received more recognition than other black playwrights of the Harlem Renaissance period, winning several competitions.  She presented several plays with W.E.B. Du Bois' Krigwa Players, of which she was a member from 1926 to 1928.  Spence was also a mentor to theatrical producer Joseph Papp, founder of The Public Theater and the accompanying festival currently known as Shakespeare in the Park. Cecil Arthur Broadhurst (May 8, 1908 - December 16, 1981) was a Canadian artist, songwriter, actor and playwright, who had a passionate interest in and love for all things Western.  At age 15 he began his lifelong commitment to painting, studying under LeMoine Fitzgerald and Frank Franz Johnston A.R.C.A. members of Canada's renowned Group of Seven (artists).  In 1932 he launched out on his own, but the Great Depression in the 1930s led him to other fields: among them flying as a Bush pilot, radio and theatre, followed by college and a year at the Detroit Art Academy.  A Canadian producer asked him to paint a stage set for him, which prompted Broadhurst, a relative of George Broadhurst, New York theatrical producer and founder of New York's famed Broadhurst Theatre, to focus his talents on the theatre and his gift for songwriting.  He subsequently wrote over a hundred cowboy songs, including ""There'll be a New World Beginning from Tonight"" which became an annual fixture as the rousing finale of the hugely popular Christmas concerts of Malcolm Sargent at London's Royal Albert Hall.  In 1940 He appeared singing one of his cowboy songs in the movie "Susan and God" starring Joan Crawford. The Sound of Musicals was a 2006 four part BBC series starring several different musical theatre actors and some other professional singers who performed acts from different musicals.  Each week the standard cast was joined by a celebrity guest host who also performed their favourite numbers.  The show also featured interviews with people involved in musical theatre such as Andrew Lloyd Webber, and Cameron Mackintosh.
Answer: Cameron Mackintosh