Watson put wah wah wow into R&B

Wah Wah Watson played on some of the biggest hits of the 70s as funk met psychedelia. Photo / Echoes/Redferns

Wah Wah Watson, aka guitarist Melvin Ragin, who died aged 67 last month, was the little-known name behind some of the best-loved, most-hummed R&B music ever recorded; among the songs that he played on were Let's Get It On by Marvin Gaye, Papa Was a Rolling Stone by the Temptations, and Rose Royce's disco classic, Car Wash.

The last two were produced by Norman Whitfield, the presiding genius in Motown's studios as the label engaged with psychedelia, and it was he who in 1971 gave the 21-year-old Ragin his break on a session accompanying Edwin Starr. Adjudged a success, Ragin became a regular sideman with the Funk Brothers, Motown's in-house backing group in Detroit.

There, Ragin heard the unusual effects that guitarist Dennis Coffey was fashioning with a wah wah pedal for the Temptations on tracks such as Ball of Confusion. The effect was akin to that of crying - hence the name, which Ragin then adopted as his musical persona.

Jimi Hendrix had been an early proponent of the pedal, for instance on Voodoo Chile, and its rhythmic potential was soon to become familiar (and much imitated) through Charles Pitts' playing on the theme from Shaft. Yet Ragin was frustrated at first by its limitations and became adept at producing a wider, more subtle range of sounds with it.

These were heard first in 1972 on Papa Was a Rolling Stone, with Ragin's prowling guitar creating a template for urban soul. He also played on Marvin Gaye's masterpiece, the album What's Going On, before adorning the singer's paeans to desire, Let's Get It On, and I Want You.

Ragin was born at Richmond, Virginia, on December 8, 1950. His father was a preacher; his mother bought him his first guitar - for $15 - on condition that he learned to play it.

During the 1970s, he featured on records such as ABC by the Jacksons, I Will Survive by Gloria Gaynor and Michael Jackson's Off the Wall. He also appeared on Blondie's album Autoamerican (1980).

In 1977, he released a solo LP, Elementary. Although the advent of the synthesiser led to less demand for his skills in the decade that followed, he became a much-liked member of Herbie Hancock's ensemble, despite a reputation for making particularly cutting jokes about other musicians.

Following the resurgence of urban soul at the turn of the millennium, Ragin worked with many of the new generation of R&B singers, including Angie Stone, Maxwell and Alicia Keys.

Ragin died on October 24 and his wife, Itsuku Aono, survives him.