The pop music industry has lost one of its most colourful characters, and accountancy one of the few who could make that trade seem glamorous.

Allen Klein, the brash and occasionally brilliant entrepreneur who was once one of the most powerful men in music, has died in New York at the age of 77, after complications from Alzheimer’s. Famed as a shark in the murky waters of the music business, blamed for the break-up of the Beatles and self-proclaimed as a wheeler-dealer who never let ethics get in the way of a good deal, Klein rose to prominence in the 1960s by assiduous application of accounting methods to the music industry.

As audits of record company books revealed gaping holes, musicians appointed Klein as their accountant and others soon turned to him as a manager, for his abrasive but effective negotiating style.

His appeal to the Rolling Stones was as a “gangster figure” who appeared to be outside the establishment. Renegotiating the Stones’ contract with Decca, Klein told the company’s chairman that he hoped his record executives could sing, “because you’ve just lost the Stones”. Decca eventually payed a far higher price to retain their services.

John Lennon persuaded his fellow Beatles to appoint Klein as their manager because he wanted “a real shark, someone to keep the other sharks away.” Recalling his career in 2002, Klein said: “I never wanted to be a manager. It was going over the books that I loved.”

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