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Friedrich Grützmacher, a German cellist and composer of the 19th century, is renowned for his significant alterations to Luigi Boccherini's B flat Major Cello Concerto. Grützmacher's modifications aimed to enhance the technical and musical aspects of the concerto, making it more challenging and appealing to both performers and audiences. His revised version became widely known and performed, contributing to the enduring popularity of Boccherini's composition in the cello repertoire.