He began his artistic career by accompanying great singing stars: Georges Guétary, Lucienne Delyle, Suzy Delair, Charles Trenet.
He conducted the orchestras of radio, television and many theaters (Mogador, Chatelet Theatre in Paris and province).
But his two most successful hits were dedicated to the couple Marcel Merkès and Paulette Merval [fr], Michael Strogoff (1964) and Vienne chante et danse (1967).
Most of his career continued essentially in the province: C'est pas l'Pérou (1976), Quadrille Viennois where he mingled tunes by Franz von Suppé and his own compositions, and La peur des coups after Courteline, played in Tours in 1977.
Ledru's 1953 song "Téléphonez-moi chérie", co-composed with Rene Denoncin and Maria Veldi, was recorded by Tino Rossi and others.