e was born in Buenos Aires, in the porteño neighborhood of Caballito. He began to study bandoneon at age nine with a teacher in his neighborhood, José Zacarnino. After 1945 he continued with the great maestro Francisco Requena. He began his public appearances with a juvenile orchestra led by Ramón Damp. Thereafter and for a year and a half, from January 1st, 1950, he played in the orchestra led by the Rosario woman, Ebe Bedrune, known as the Tango Woman (La Mujer Tango).

He reminds us that at that time there were three tango orchestras playing daily at downtown venues. Giannini succeeded in appearing at the Ebro Bar on Corrientes Street. His partners in that orchestra were the violinists Elías Garnik, Luis Straser and José Carli.

In his long career in tango, maestro Giannini played in the orchestras headed by Domingo Federico and by Lorenzo Barbero, whose orchestra was known as La Orquesta de la Argentinidad in which he stayed for nine years, and was lead bandoneon for five years.

He was also member of the Orquesta Símbolo «Osmar Maderna», conducted by Aquiles Roggero, and one year with the one fronted by maestro Miguel Caló with which he played in several recordings; later in the Francini-Pontier orchestra, when Julio Sosa was on vocals, and in the group led by José Colángelo.

Besides accompanying a large number of singers, for many years he was member of the Mariano Mores ensemble, with which he ended his career as bandoneon player in 2011.

He also appeared at the venue called La Ciudad, on Talcahuano Street.

From 1990 to 1995, he was guest player with the Sexteto Mayor, at the shows Tango Argentino and Tango Pasión. He made tours of the United States, Colombia, Panamá, Peru, Chile, Ecuador, Costa Rica.

Giannini recorded with Juan Sánchez Gorio and played from time to time with Orlando Trípodi, in 1963, 1966 and l972, and with Osvaldo Berlingieri. The bandoneon section of the Trípodi orchestra in 1966 was lined up by: José Libertella, Carmelo Gentiluomo, Felipe Ricciardi, José Riciardi and Tomás Giannini.

In 1972, with Miguel Caló until the leader’s death, the personnel was: Tomás Giannini, Héctor Lettera, Oscar Basil «El Turco» and Santos Maggi on bandoneons, Orlando Trípodi on piano; Juan Carlos Vallejos on double bass; Aquiles Aguilar, José Amitrain, Pedro Aguilar and Osvaldo Rodríguez on violins.

In 1996 he was with the dancer Julio Bocca on a tour of 19 cities of Spain, Egypt, Italy, England, teaming up as duo with the pianist Atilio Stampone at the respective openings of the finale of the show.