Born in Novara around 1660, Carlo Giuseppe Testore had already moved to Milan in the last decades of the seventeenth century, probably coming into contact with the main luthier active in the city, Giovanni Grancino. Shortly thereafter he began to sign his instruments, working in Contrada Larga "under the sign of the eagle" as his labels reported. His production extended to the beginning of the eighteenth century and was continued by his sons Carlo Antonio and Paolo Antonio Testore.
The style of Carlo Giuseppe was thus influenced by the work of Grancino in his elegant, compact body model and in the F-hole pattern, which have a tilted positioning, wide stems and rather horizontal wings. The most recognizable element is the volute, which has a very typical oblique flattening. Similarly to the other members of the family, Carlo Giuseppe Testore's cellos are particularly appreciated.