What is "tonkunstler-societat"

The Tonkünstler-Societät ("Society of Musicians") was a benevolent society for musicians in Vienna, which lasted from the mid 18th century to the mid 20th. Its purpose (New Grove) was "to support retired musicians and their families". Beginning in 1772, the Society mounted a series of benefit concerts, often with large forces of performers, at which were performed works by leading Classical-period composers, including Joseph Haydn, Wolfgang Amadeus Mozart, and Ludwig van Beethoven.