A Stradivari violin dating from 1729 has been auctioned for $2.73m (£1.38m) at Christie's in New York, about twice the amount it was expected to fetch.
Buying agent Ric Heinl (right) said it was a "great" violin for concerts
Known as the "Solomon, Ex-Lambert", the instrument went to an anonymous bidder.
It was described as "a bargain" by Ric Heinl, the buying agent representing its new owner, who said it was worth "considerably more" than the sum paid.
Violins made by Italian Antonio Stradivari are highly sought-after and are rarely offered for sale.
This particular instrument took its name from its two most recent owners - Seymour Solomon, co-founder of Vanguard Records, and Murray Lambert, a British concert violinist in the 1920s and '30s.
Christie's said the instrument came from Stradivari's "mature period".
It retained "the bold outline, superb arching and quality materials which account for the power, sonority and tonal balance his work is recognised for", the auction house added.
Another Stradivari - "The Hammer" - set a world-record auction price for a musical instrument last May, when it was sold for $3.54m (£1.79m).