Deep Purple's Jon Lord, shown in September 1969, died after a battle with pancreatic cancer. (PA Wire/AP)

Jon Lord, the keyboardist for Deep Purple, the band whose hard rock anthems laid the groundwork for heavy metal music, died July 16 at a hospital in London. The British musician, who had pancreatic cancer, died of a pulmonary embolism. He was 71.

“One of the biggest, baddest, heaviest sounds in heavy metal,” Slash, the former Guns N’ Roses guitarist, tweeted after the death was confirmed on Mr. Lord’s Web site.

In a career spanning four decades, Mr. Lord recorded 16 albums with Deep Purple, played with groups ranging from the Kinks to Whitesnake, and toured extensively as a solo artist, even after his cancer diagnosis.

Mr. Lord rose to prominence in the 1970s as a member of Deep Purple, and he co-wrote many of the band’s biggest hits, including “Smoke on the Water,” “Black Night” and “Strange Kind of Woman.” The band sold tens of millions of albums, and Mr. Lord backed up his rock star swagger with the driving sound of the Hammond electric organ, popularly used on jazz tracks of the era.

Mr. Lord, a classical music aficionado, boasted in a 1973 interview, “We’re as valid as anything by Beethoven.”

The Guinness Book of World Records awarded Deep Purple the distinction of “world’s loudest band.” Many reviewers found it hard to disagree. In a 1972 review of the album “Machine Head,” Rolling Stone music critic Lester Bangs wrote that the band delivered “the Sound, the rushing, grating crunch of the hard attack” with a pace that is “blistering, almost too fast for comfort.”

Jonathan Douglas Lord was born June 9, 1941, in Leicester, England. He described his childhood to his hometown newspaper, the Leicester Mercury, as “perfect.” His father, it was reported, “packed socks by day and played sax by night,” and Mr. Lord began playing classical piano as a child.

“It was always homework and piano lessons,” he said. “Something had to give – and it was usually homework.”

Mr. Lord moved to London in the early 1960s to study acting at the Central School of Speech and Drama, a move that coincided with London’s blues boom. He was swept up by the sounds of blues, jazz, rock-and-roll, and rhythm and blues, and he was particularly drawn to the music of two American musicians, the soul-jazz organist Jimmy McGriff and rock pianist-singer Jerry Lee Lewis.

Mr. Lord began playing with blues and rock acts. As a studio musician, he said, he contributed a keyboard part on the Kinks’ 1964 recording of “You Really Got Me.”

“All I did was plink, plink, plink,” he said of the recording. “It wasn’t hard.”

In 1968, he founded Deep Purple with bassist Nick Simper, guitarist Ritchie Blackmore, drummer Ian Paice and singer Rod Evans. The group found initial success covering songs such as Neil Diamond’s “Kentucky Woman.” A year later, Evans was replaced by singer Ian Gillan, and Deep Purple veered into the hard rock phase that would come to define the band.

At the center of Deep Purple’s sound was the acoustic battle between Blackmore’s searing guitar and Mr. Lord’s Hammond organ, fortified with the power of an amplifier. Initially, Mr. Lord tried using a Leslie amp, but it wasn’t loud enough to compete with Blackmore’s intensity.

Next, he tried tapping straight into the amplifier in the back of the organ and took the line into 200-watt Marshall speakers.

“The sound was astonishing,” he said in a 2011 interview with “It was like a huge beast leapt out of these Marshall cabinets. . . . What I was getting was more of the tap and the click and the kind of raw internal sound of the Hammond organ.”

In addition to his rock compositions, Mr. Lord wrote numerous classical and orchestral works. Deep Purple performed his “Concerto for Group and Orchestra” with the Royal Philharmonic Orchestra at London’s Royal Albert Hall in 1969. Music critic Don Heckman applauded Mr. Lord’s ambition but not his execution.

In a New York Times review of a recording of the 1969 concert, Heckman wrote that while Mr. Lord was “surprisingly competent,” the piece sounded “like a crazy quilt of rock music, Benjamin Britten, Ralph Vaughan Williams and, I’m afraid, Malcolm Arnold.”

Dave Simpson, music critic for the London Guardian, more recently described the Lord concerto as “either an innovative fusion of rock and classical music, or an epic, pretentious folly: one of the key inspirations behind Spinal Tap.” Spinal Tap, a fictional heavy metal band, is the subject of a 1984 mock documentary satirizing hard rock groups of the 1970s and 1980s.

For eight years, Deep Purple topped the charts and toured the world, filling stadiums with the sound of Blackmore’s guitar and Mr. Lord’s grinding organ. Mr. Lord was a mainstay of the band, which went through several lineups before splitting in 1976.

Mr. Lord started his own ensemble, Paice, Ashton and Lord, which released one album, “Malice in Wonderland.” In 1978, he joined the band Whitesnake, founded by former Deep Purple singer David Cloverdale. The group played what Mr. Lord described as “white R&B” in the middle of the punk revolution.

Mr. Lord left Whitesnake in 1983 — before the band’s sound turned from bluesy soul to “hair metal” — and joined a reunited Deep Purple the next year. Mr. Lord remained with Deep Purple until 2002. The band still tours today.

His first marriage, to Judith Feldman, ended in divorce. Survivors include his wife, Vickie Gibbs, a daughter from his first marriage, and a daughter from his second marriage.

Most recently, Mr. Lord was the composer-in-residence at the philharmonic orchestra of Haden, Germany.

“I have this bee in my bonnet about trying to combine different ways of looking at music,” Mr. Lord said in an interview for German television. “To me, it seems the most natural thing in the world.”