Here, listen to what a $45 million Stradivari viola sounds like

If you're an exceedingly rich person who's also very good at the viola, you're definitely psyched about an upcoming auction at Sotheby's.

A rare Stradivari viola, named the "Macdonald" viola for a nineteenth-century owner, is up for sale and it's expected to fetch $45 million.

You might be thinking something along the lines of, "What?!" That's an understandable reaction. Nothing played on this instrument will ever sell as many copies — or provide you with the deep satisfaction — of Ke$ha and Pitbull's "Timber." The thing doesn't even have bluetooth connectivity.

There is a reason the viola is so coveted, beyond the obvious one, which is that very rich people like to buy rare things that cost shocking amounts of money.

In this case, it all comes down to the maker and the instrument.

This viola was made by Antonio Stradivari. Stradivari, an Italian instrument maker born in 1644, established himself as the world's premier maker of violins and violas over a 70-year career. Six hundred Stradivari violins exist, but only 10 violas. And the "Macdonald" viola, made in 1719, is the crown jewel of that bunch. It sounds great, it's in great shape, and until 1987, it featured in the Amadeus Quartet, where it was played by one of the greatest violists of the 20th century, Peter Schidlof.

The record sale price of a musical instrument stands at $15.9 million, set in 2011 by another Stradivari: the "Lady Blunt" violin. Whether or not the "Macdonald" viola hits its target of $45 million, that record is going down.