'Fifth Beatle' producer George Martin dies age 90.

Sir George Martin, the composer and producer dubbed “The Fifth Beatle” for the major role he played in bringing The Fab Four to global prominence in the 1960s, has died aged 90.

Beatles drummer Ringo Starr was first to mourn the producer’s passing on social media. The news was later confirmed by the Universal Music Group and Martin’s management firm.

“We can confirm that Sir George Martin passed away peacefully at home yesterday evening,” Adam Sharp, of CA Management, said in a statement.

“The family would like to thank everyone for their thoughts, prayers and messages of support.”

Founding member of the band Paul McCartney expressed his grief over Martin’s passing on Facebook, calling him a “second father”.

“From the day that he gave The Beatles our first recording contract, to the last time I saw him, he was the most generous, intelligent and musical person I’ve ever had the pleasure to know,” McCartney wrote.

"The world has lost a truly great man who left an indelible mark on my soul and the history of British music."

Originally a producer of comedy records, Martin was introduced to the work of The Beatles via their manager, Brian Epstein, in 1962, when the band was trying unsuccessfully to find a home for its earliest recordings.

"The recording, to put it kindly, was by no means a knockout," Martin wrote in his memoir, All You Need Is Ears, of those demos.

"I could well understand that people had turned it down. But there was an unusual quality of sound, a certain roughness that I hadn't encountered before."

After a meeting at Abbey Road studios in London, Martin found he liked the four young men, particularly for their quick wits, and thought they had a bright future.

But, he told Melody Maker magazine: "As composers, they didn't rate. They hadn't shown me that they could write anything at all."

In one of their earliest sessions, Martin convinced The Beatles to speed up the song Please Please Me, turning it from a ballad to an up-tempo rock and roll number. It became one of the Liverpool band's first hits.

Through his work with the band, Martin became one of the greatest producers in the history of popular music, snagging dozens of number-one hits in the UK and the US across a six-decade career.

The Beatles, thanks in part to Martin and engineers such as Geoff Emerick, were renowned for their use of studio techniques that were complex for the pre-digital age, for example in Strawberry Fields Forever, which saw Martin melding two different studio takes into one.

On In My Life, from the 1965 album Rubber Soul, the solo Martin performed was recorded at half-speed, meaning that when it was played back at full-speed, it was unusually high-pitched and fast.

The producer also experimented with tape loops and the double-tracking and reversing of sounds, techniques used widely on songs like Tomorrow Never Knows, from Revolver (1966).

Martin was also a capable musician, adding solos and arrangements on songs such as I Am The Walrus.

He also developed a reputation for his arrangements with the band. He convinced Paul McCartney to put a string quartet on Yesterday, and wrote the string arrangements for Eleanor Rigby, later saying it was based partly on the score for Alfred Hitchcock's Psycho.

After the band split, he built the Air Studios on the Caribbean island of Montserrat and went on to work with other artists including Bob Dylan, Sting and Elton John.

He also recorded two of McCartney's solo albums, Tug of War and Pipes of Peace.

Martin was inducted into the American Rock and Roll Hall of Fame in 1999 for his outstanding contribution to music.

Thank you for all your love and kindness George peace and love xx????? pic.twitter.com/um2hRFB7qF

— #RingoStarr (@ringostarrmusic) March 9, 2016

Sir George Martin. Gentleman and legend. R.I.P. — Boy George (@BoyGeorge) March 9, 2016

This post originally appeared on the ABC.

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