Younger brother of Riccardo Antoniazzi and son of Gaetano, he was born in Cremona in 1862. He had a rather disorderly and wandering life, working alternately with his brother, independently, and also for the workshops of Leandro Bisiach, Monzino and the Barlassina company.
His violin making recalls that of his brother, even if Romeo often preferred to leave his corners and edges decidedly more massive and, in a similar way, his heads are also heavier and with a larger eye, while with his brother he shares the oval shape of the back of the peg-box and the deep fluting of the volute, especially when viewed from the front. Generally his lutherie is coarser and less refined than Riccardo's. Romeo used classical Cremonese models interpreted personally, especially those of Guarneri del Gesù towards the end of his career. He died in Milan in 1925.
