Sony, which 25 years ago changed the way the world listened to music with the Walkman, said it would release a product by the end of the year in hopes of dethroning Apple's hot-selling iPod.

"We are confident of being able to offer by the end of the year a product that is much more competitive than the iPod," Sony president Kunitake Ando said.

Ando said Apple's success was in developing a product that is simple to use.

"We have to develop software that makes use of our products more intuitive and simple," he told reporters.

Apple jumped back into profit through the iPod, which allows users to carry a song library in their pocket and which hit the stores in October 2001.

It was a continuation of the revolution launched in 1979 by Sony, which created a new culture of portable music with the Walkman.

Ando dismissed rumors of Sony buying Apple, saying it "has become too expensive because of the success of iPod."

"We have put in place a very aggressive plan to become number one again" in portable music, said Nobuyuki Idei, Sony chairman and chief executive officer