Piero was a native of the Pisa region and taught himself violin making from the age of 16. After the second WW he became associated with the Soderci family. His output is small, probably less than 100 instruments. His violas are highly regarded, winning the gold medal for viola in the 1976 International Triennal Competition.
Badalassi had a personal and classical model; his instruments are known to be well finished. He was highly respected as a repairer and restorer. His other awards include at Cremona 1937, 1965, 1973. Piero Badalassi in Pisa / Faceva l’Anno 1946 Piero Badalassi-fece / in Pisa l’Anno 1952.