TOKYO (AP)- As a young man, aspiring opera singer Norio Ohga wrote to Sony to complain about the quality of its tape recorders.

That move changed the course of his life, as the company promptly recruited the man whose love of music would shape the development of the compact disc and transform the Japanese electronics maker into a global software and entertainment empire.

Sony's president and chairman from 1982 to 1995, Ohga died Saturday in Tokyo of multiple organ failure, the company said. He was 81.

Ohga's connection to music steered his work. The flamboyant music connoisseur insisted the CD be designed at 12 centimeters (4.8 inches) in diameter to hold 75 minutes worth of music - in order to store Beethoven's Ninth Symphony in its entirety.

From the start, Ohga recognized the potential of the CD's superior sound quality. In the 1970s, when Ohga insisted CDs would eventually replace record albums, skeptics scoffed. Herbert von Karajan, Stevie Wonder and Herbie Hancock spoke up in defense of Sony's digital sound.

Sony sold the world's first CD in 1982 and CDs overtook LP record sales in Japan five years later. The specifications are still used today and fostered the devices developed since.

``It is no exaggeration to attribute Sony's evolution beyond audio and video products into music, movies and game, and subsequent transformation into a global entertainment leader to Ohga-san's foresight and vision,'' Sony Corp. Chairman and CEO Howard Stringer said Saturday, using the Japanese honorific.

Some decisions made during Ohga's presidency, such as the $3.4 billion purchase of Hollywood studio Columbia Pictures, were criticized as unwise and costly at the time. But Ohga's focus on music, films and video games as a way to enrich the electronics business helped create Sony's success in his era.

``We are always chasing after things that other companies won't touch,'' Ohga said in a 1998 interview with The Associated Press.

``That is a big secret to our success.''

Shattering the stereotype of the staid Japanese executive, the debonair Ohga was never shy, his hair neatly slicked back, his boisterous manner exuding the fiery yet naive air of an artist. His persona added a touch of glamour to Sony's image at a time when Japan had global ambitions.

An experienced pilot, Ohga at times flew the company plane himself for business trips. A gourmet, he boasted about his roast beef. His hobby was cruising on his yacht.

Joey Carbone, a Los Angeles-based composer and producer of dozens of Japanese pop songs, met Ohga in 1986 after Carbone wrote several hits for commercials for everything from cassette tapes to Honda scooters on Sony's music label.

He remembers Ohga as an outgoing, international-minded executive who could talk about business and a wide variety of music with equal aplomb. Ohga's office was covered with photos of himself with different artists, both Japanese and international.

``He looked like an actor. He was very outgoing,'' Carbone said Saturday. ``He was very, how can I say it _ not introverted. He was always talking, always smiling and laughing. He seemed to have a real love of life and music. He seemed to really love what he was doing.''

Chairman of the Tokyo Philharmonic Orchestra since 1999, he continued to conduct there a few times a year. In 1993, he conducted the Metropolitan Opera Orchestra at Lincoln Center's Avery Fisher Hall in a charity event funded by Sony.

Ohga often compared leading a company to conducting an orchestra.

``Just as a conductor must work to bring out the best in the members of his orchestra, a company president must draw on the talents of the people in his organization,'' Ohga said in a 1996 Sony publication.

Sony started amid the destruction and poverty after World War II and built itself on the popularity of transistor radios, the Walkman, the Trinitron TV, the CD _ shaping the history of modern electronics.

Ohga had graduated from Tokyo National University of Fine Arts and Music in 1953 and Berlin University of the Arts in 1957. He was set to pursue a career as a baritone opera singer when Sony co-founders Masaru Ibuka and Akio Morita, intrigued by his complaints about the sound quality of Sony tape recorders, recruited him to the company.

He was a Sony executive by his 30s, a rarity in a Japanese company. He was appointed president of CBS Sony Records in 1970, chairman of what later became Sony Corp. of America in 1988, and chief executive of Sony in 1989. He left the day-to-day business in about 2000.

The company says he was key in building the Sony brand, especially working on design, as well as quality, to make products that looked attractive to consumers.

``Norio Ohga was a brilliant and innovative businessman whose visionary leadership had a profound impact on the way people experience entertainment throughout the world,'' Sony Pictures Entertainment Chairman and CEO Michael Lynton and Co-Chairman Amy Pascal said in a statement.

Ohga had tried to lead a double life of artist and Sony man.

One day, he dozed off from exhaustion in the stage wings while waiting to go on in the ``The Marriage of Figaro,'' rushed in from the wrong direction and watched his embarrassed co-stars stifling giggles.

He gave up his opera career but still promoted classical music in Japan by supporting young musicians and concerts.

Sony has encountered difficulty in recent years, falling behind in flat-panel TVs to rivals like Samsung Electronics Co. of South Korea, as well as in digital music players to Apple Inc. It remains unique in having a Hollywood studio, a music recording business, and the blockbuster PlayStation video-game unit that Ohga helped create, though critics note it has never fully realized the benefits of owning both electronics and entertainment divisions.

Ohga is survived by his wife, Midori. Sony said a private wake will be held later.