Double Bass Concerto in A major (2) Domenico Dragonetti
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Music's greatest inventions: amazing, mad and brilliant instruments
The invention of the clarinet by Johann Christoph Denner (though it's rumoured his son was involved in the process too) was significant, as it was the first Western single-reed instrument. Thanks to popularisation by Mozart among others, the clarinet fell into regular orchestral use and has been used ever since.