A spokeswoman for the company he founded said he passed away in Milton Keynes, southeast England, on Thursday morning. She could not confirm reports that he had been suffering from cancer and had a series of strokes.

"It is with profound sorrow that we announce the passing of our beloved founder and leader for the past 50 years, Jim Marshall," said a statement on his company's website.

"While mourning the Guv'nor though, we also salute a legendary man who led a full and truly remarkable life."

Tributes poured in for a man credited with helping to shape the sound of guitar rock.

"The news of Jim Marshall passing is deeply saddening," former Guns N' Roses guitarist Slash said in a message on Twitter. "R & R will never be the same w/out him. But, his amps will live on FOREVER!"

His company said in a written tribute: "Your memory, the music and joy your amps have brought to countless millions for the past five decades and that world-famous, omnipresent script logo that proudly bears your name will always live on."

TOWNSHEND, HENDRIX AMONG EARLY CLIENTS

Marshall is revered as one of the four forefathers of rock music equipment along with Leo Fender, Les Paul and Seth Lover.

Born in London in 1923, he started out as a drummer before going into business and founding Marshall Amplification in 1962.

In around 1960, a young Pete Townshend, later lead guitarist for The Who, first suggested to Marshall that he expand his music shop to sell guitars and amplifiers as well as drums.

According to an interview Marshall gave several years ago, the London store quickly turned into a "rock'n'roll labour exchange", and Marshall hired an engineer employed by a record label to help him build prototype amplifiers.

Marshall rejected the first five attempts but was happy with the sound of the 6th -- he received 23 orders for the new equipment on the first day alone.

Legendary musicians including Jimi Hendrix and Eric Clapton were among the early Marshall amp users.

When Hendrix walked into the store, Marshall recalled thinking to himself: "Bloody hell, here's another American guitarist wanting something for nothing."

But the guitarist paid the full price for everything he purchased without delay.

Marshall was awarded an OBE honor for services to the music industry and to charity, and he has donated millions of pounds to "worthy causes", according to his website.

They included the Royal National Orthopaedic Hospital in Stanmore where he was reportedly treated for tuberculosis as a child.

(Reporting by Mike Collett-White, Editing by Christine Kearney)

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