Haynes was a master
silversmith. He was the son of a
sea captain and a school teacher. Haynes established his flute-making shop, Wm S Haynes Co., in Boston. It remained in Boston until 2010, when it moved to Acton, Massachusetts. Haynes
patented his distinctive flute design in 1914, and the company has since become a provider of
silver and
gold instruments to many of the world's most prominent
orchestral,
chamber and
jazz musicians. High-profile
soloists to have performed on a Haynes flute include
Georges Barrère and
Jean-Pierre Rampal. Most notably, the company made silver, gold, and 90/10 platinum-iridium alloy flutes for Barrère.
Edgard Varèse's piece,
Density 21.5, was composed for Barrère's debut on his platinum Haynes flute; 21.5 was a reference to the density of platinum. At US$3,750 in 1935, it cost about four times more than his gold one purchased in 1927 (in real dollars: US $1,250 in 1927 and US$3,750 in 1935 are about US $16,000 and US$65,000, respectively, in 2014 dollars). ==Death and legacy==