John Spencer Davis

John Spencer Davis Jr., an interior designer, artist, and musician, died on March 25 in Alexandria, Va. Mr. Davis, whose last years were spent on Maidstone Lane, East Hampton, in a house owned by his parents for about 50 years, was 64. He had been ill for a long time, his family said.

Known as Jock, he was born in Washington, D.C., on Oct. 24, 1949, to Spencer Davis and the former Sarah Kimball. He attended the Landon School in Bethesda, Md., until ninth grade, and graduated in 1968 from the Salisbury School in Connecticut.

A year later he became a professional recording artist. With his band, Swamp Gas, he made two albums that were produced by Buddha Records in conjunction with Artie Kornfeld, who produced the Woodstock Festival that same year. Mr. Davis and the band members lived at the time on a farm in upstate New York, and often appeared on the same stage as the Grateful Dead.

He also lived for a while in Aspen, Colo., but by the early 1970s he was in New York City, working as a studio musician and songwriter for both radio and television. Throughout his life, his family said, he never stopped playing music, later contributing the song “Tell Me” to “Metropolitan,” a film directed by Whit Stillman that received an Academy Award nomination in 1990.

On Sept. 18, 1982, he married Denise Wilburn Davis in Alexandria, where the couple made their home. The next year, with his mother, he opened Living Well, an interior design business in Washington, where they frequently worked with East Hampton-based clients. The name of the business was later changed to Jock Davis Design Group.

Mr. Davis’s work was published in Southern Accents magazine, The Washington Post, and American City and Country, which featured the Bridgehampton house he decorated for the late Peter Jennings. He retired from the business in 2008.

He was an accomplished artist as well, with his design clients often commissioning his paintings.

His parents were longtime members of the Maidstone Club. Though their main residence was in Bethesda, the family spent as much time as possible in East Hampton, summers, weekends, and holidays, and Mr. Davis had many friends here. He knew a number of resident artists, Willem de Kooning among them.

In 2003 Mr. Davis, his wife, and his mother came to live on Maidstone Lane year round. Sarah K. Davis died in November at the age of 87.

Mr. Davis is survived by Denise Wilburn Davis, his wife of 31 years. He also leaves a brother, Christopher Kimball Davis of Moss Beach, Calif., and a sister, Tracy Tucker Davis, of East Hampton.

A memorial service will be held on May 3 in Virginia.