An anonymous bidder paid $1.2 million for a cello made by Antonio Stradivari about 1698 - a world record auction price for a musical instrument, the Sotheby's auction house said.

The cello, known as the Chol-mondeley after a previous owner, was auctioned Wednesday. The seller asked to remain anonymous.The previous record for a musical instrument was $890,000 paid by an anonymous South American in London on March 31 for a violin known as the Marie Hall that was also made by Stradivari, an Italian.

The previous record for a cello was $393,000 paid in 1984 by Robert Cohen, an eminent London cellist, for a Stradivari instrument known as the Bonjour.

Sotheby's said several people were bidding for the Cholmonde-ley "in a relaxed way." They said they were not surprised by the price.

"The Cholmondeley is so well made that it almost plays itself - as if it had cruise control," said Adam Watson, the cataloguer of Wednesday's auction.