The “Kux, Castelbarco” Stradivari Viola Sells for £2.5 Million

Sold by the Tarisio auction house in London, the c.1720 viola is one of only twelve violas that Antonio Stradivari made across six decades 

On October 31, 2022, the “Kux, Castelbarco” Stradivari viola was sold to a private owner at London’s Tarisio auction house for £2,520,000, after receiving 26 bids and one extension.

“Bidding was active and competitive,” Tarisio posted on Instagram. “We are proud to have represented this historic instrument!”

The “Kux, Castelbarco” viola was initially a viola d’amore — a six-stringed viol that fell out of fashion during the 18th century in Stradivari’s lifetime, when violins, violas, and cellos drew popularity, according to Tarisio. 

Around 100 years later, when viola d’amore instruments were less valuable, French luthier Jean-Baptiste Vuillaume came across the “Kux” and transformed it into a viola after noticing the original was built more like it with its viola-shaped corners, sound holes, and edges that Stradivari similarly used for his contralto violas.

Due to the instrument’s original back being lost, a replacement was made by Vuillaume c.1850, when he reconstructed parts of the viola around the same time and selected a head for it crafted by Nicolo Amati c.1620. The top and ribs of the “Kux” are Stradivari’s originals c.1720.

Further, the instrument’s original twelve-string head was gifted to Conservatoire de Paris’s instrument museum by Vuillaume in 1873 and is now part of the collection at Musée de la Musique.

The viola is named for one of Vuillaume’s best customers, Milanese nobleman, violinist, and composer Don Cesare Pompeo Castelbarco, who was its owner, along with at least seven Stradivari instruments. After Castelbarco died in 1860, the viola was bought and sold several times until it landed with Wilhelm Kux in 1914. Kux was a Viennese banker, amateur musician, and music patron.  

The viola has been played by Adolf Busch and Bronisław Huberman. In 2009, violist Pavlo Beznosiuk performed on the “Kux” in a recording of Mozart's Sinfonia Concertante with violinist Rachel Podger, who described it as having “the most amazing resonance.

The “Kux” is one of 12 violas that Antonio Stradivari created during his lifetime from his twenties until his late eighties. All except two of the 12 violas are currently in the possession of foundations or state-owned collections.