Kiyoshi Koyama, widely regarded as Japan’s pre-eminent jazz journalist, who covered the music’s development throughout the 1960s and ’70s before becoming a producer of archival albums, died on Feb. 3 in Kashiwa, Japan. He was 82.

Katherine Whatley, a journalist and friend of Mr. Koyama, said the cause was stomach cancer.

As the editor of Swing Journal, the leading jazz magazine in one of the world’s most jazz-loving countries, Mr. Koyama rigorously covered the music being made on both sides of the Pacific Ocean, often traveling to the United States.

He went to New York in the summer of 1969 to report on the city’s avant-garde scene, which was abuzz with insurgent energy, and paid a consequential visit to the saxophonist Ornette Coleman, a creator of free jazz, who had recently moved into a loft space at 131 Prince Street in SoHo. Mr. Koyama watched Coleman’s band rehearsing and spent time with him in his living quarters above the rehearsal space.

“My style is to meet a musician and see his home, and find out how they live. That shows me another side of the musician. That’s interesting to me,” Mr. Koyama said in a 2015 interview with Ms. Whatley. “That’s why I visited Ornette’s place, too. You can find a different side of a musician from the one on stage.”