Rudolph Isley, who held twin roles within the influential vocal group the Isley Brothers as a mellifluous concord singer and co-writer of lots of their best hits, died on Wednesday at his house in Chicago. He was 84.

He died in his sleep, his brother Ernie mentioned, including that he was unaware of any well being points his brother may need had.

Mr. Isley spent a lot of his three a long time with the Isley Brothers harmonizing together with his brother O’Kelly in assist of Ronald Isley’s lead vocals. However he additionally sang lead on some notable tracks. On “I’ve Bought to Get Myself Collectively,” recorded in 1969, his gentlemanly tone gave the tune a contact of grace. He additionally lent a suave result in the group’s fleeting entry into the disco area, “It’s a Disco Night time (Rock Don’t Cease),” which was a membership hit in america in 1979 and reached the Prime 20 in Britain.

The Isley Brothers have been at all times modern, and within the Seventies and ’80s Mr. Isley made a style assertion of his personal by carrying hats and furs and carrying a bejeweled cane, giving the Isleys added panache.

He and his brothers wrote a variety of pivotal hits, starting with “Shout,” the group’s 1959 breakthrough, which utilized the dynamic of gospel music’s call-and-response to a pop context. Additionally they wrote the enduring political anthem “Combat the Energy,” a Prime 5 Billboard hit, in addition to the Prime 10 pop hits “It’s Your Factor” and “That Girl.”

Sixteen of the Isley Brothers’ albums cracked the Billboard Prime 40, 13 have been licensed gold and 9 went platinum or multiplatinum.

In 1989, Mr. Isley retired from the mainstream music business to pursue his long-deferred dream of a profession within the ministry, though he continued to sing in church. He additionally recorded some gospel songs, and in 1996 launched a non secular album titled “Shouting for Jesus: A Loud Joyful Noise.” He and his brothers have been inducted into the Rock & Roll Corridor of Fame in 1992.

Rudolph Bernard Isley was born on April 1, 1939, in Cincinnati, the second of six sons of Sallye (Bell) and O’Kelly Isley. He started singing in church as a toddler, and through his teen years he and three of the opposite older Isleys carried out collectively and toured regionally.

”I’ve some very particular reminiscences of listening to music with my brothers after we have been younger,” Mr. Isley instructed the music journalist Leo Sacks for the liner notes to a 1999 boxed set that Mr. Sacks produced, “It’s Your Factor: The Story of the Isley Brothers.” He added: “Billy Ward and the Dominoes, now that was a gaggle. We idolized them. We obtained our personal factor collectively as a result of we by no means misplaced that concord group dynamic.”

Within the group’s early days, the eldest brother, Vernon, sang lead. He was killed at age 13 when the bicycle he was using was struck by a automobile, and Ronald grew to become the lead singer.

The Isleys have been nonetheless fairly younger when Rudolph, O’Kelly and Ronald moved to New York to pursue a document deal. Contracts with small labels led to 1 with RCA, one of many largest within the enterprise, in 1959, and shortly after that the Isleys wrote and recorded “Shout.” It bought over one million copies and got here to be acknowledged as a rock ’n’ roll basic, spawning covers by Dion, Bruce Springsteen, Garth Brooks and lots of others. (It was additionally heard in “Nationwide Lampoon’s Animal Home” and different films.)

In 1962, the Isleys had a Prime 40 hit with their cowl of “Twist and Shout,” written by Bert Berns and Phil Medley and initially recorded a yr earlier by the Prime Notes. Their recording supplied a template for the way more widespread model recorded by the Beatles in 1963.

For a quick time in 1964, the Isley Brothers’ band included a younger guitarist named Jimmy James, who would later be often known as Jimi Hendrix.

The Isleys signed with Motown in 1965. However regardless of the label’s popularity for producing hits, that they had only one of their temporary tenure there, “This Previous Coronary heart of Mine (Is Weak for You),” written by the label’s prime songwriting staff, Lamont Dozier and Brian and Eddie Holland (with Sylvia Moy). It reached No. 12 on the Billboard chart and No. 3 in Britain. Pissed off by Motown’s controlling strategy, the brothers, in an uncommon transfer for an African American act on the time, left the label to type their very own, T-Neck Data, named after Teaneck, N.J., the place they have been primarily based.

Switching to a rawer and funkier model influenced by James Brown and Sly Stone, the trio discovered a brand new métier, and a brand new business connection. Their 1969 single “It’s Your Factor” rose to No. 2 on Billboard’s pop chart and No. 1 on the journal’s R&B record.

In the beginning of the Seventies, the group expanded to incorporate the 2 youngest siblings, Ernie and Marvin, together with Rudolph’s brother-in-law, Chris Jasper; all three contributed instrumental work, and Mr. Jasper additionally sang. The outcome was a largely self-contained band, one other rarity for Black artists of the day. Collectively, they pioneered a novel rock ’n’ roll-tinged model of funk and soul. Over time, their music lined a variety of genres, from doo-wop to gospel to quiet-storm ballads.

From 1973 by 1981, all of the group’s albums went gold, platinum or multiplatinum. Many of the tracks on these albums have been co-written by Mr. Isley and the opposite members.

The group additionally scored a platinum album in 1986 with “Between the Sheets,” whose title observe supplied their sensual reply to Marvin Gaye’s “Sexual Therapeutic.” Rudolph Isley shared lead vocals together with his brother Ronald on two tracks of that album, the spacey funk quantity “Means Out Love” and the sensual grind “Gradual Down Youngsters.”

With the rise of hip-hop, the Isleys’ basic materials supplied the supply for extra samples than any act aside from James Brown and George Clinton’s Parliament-Funkadelic.

The dying of O’Kelly Isley from a coronary heart assault in 1986 hit Rudolph notably exhausting. The group’s subsequent album, “Clean Sailin’” (1987), featured simply him and Ronald on the duvet and was devoted to O’Kelly. Two years later, Rudolph stop the music enterprise.

Nonetheless, the ever-resourceful, forward-looking group endured and made a profitable comeback in 1996 with the album “Mission to Please,” buoyed by manufacturing and writing from R. Kelly. Rudolph Isley reunited together with his brothers for one evening in 2004, when the group was given a lifetime achievement honor on the BET Awards.

In March, Rudolph sued his brother Ronald, claiming that he had sought to safe a trademark for the group underneath his personal identify completely. The go well with claimed that the founding members have been “always” a “common-law partnership.”

Marvin Isley died in 2010 from issues of diabetes.

Along with his brother Ernie, Rudolph Isley’s survivors embody his spouse, Elaine Jasper, whom he married in 1958; their kids, Rudy Jr., Elizabeth, Valerie and Elaine; his brother Ronald; and a number of other grandchildren.

“Music and religion, they simply run by our blood,” Mr. Isley was quoted as saying within the “It’s Your Factor” liner notes. “I’ll have stopped singing pop music, however I’ll at all times be an Isley Brother.”

Bernard Mokam contributed reporting.