Frémaux worked with the orchestra of the Opéra de Monte-Carlo, after having been released from the French Foreign Legion (to which he had been recalled for service in Algeria) at the request of Prince Rainier. For ten years he helped build the reputation of the Monte Carlo orchestra, as well as conducting opera premieres there. He was the first music director of the Orchestre Philharmonique Rhône-Alpes (later the Orchestre National de Lyon), from 1969 to 1971.[2]
In the UK, Frémaux was principal conductor of the City of Birmingham Symphony Orchestra (CBSO) from 1969 to 1978. During his CBSO tenure, he formed the CBSO Chorus, with the baritone Gordon Clinton[3] as its chorus master.[4] In 1978 he was awarded an honorary DMus from Birmingham University; he also became a member of the Royal Academy of Music.[2] However, his CBSO tenure ended in controversy after the relationship between Frémaux and the orchestra players had broken down.[5]
In 1963, he recorded a world premiere, Marc-Antoine Charpentier’s, Dialogus inter angelos et pastores Judae in nativitatem Domini H.420, and In nativitatem Domini canticum H.314, with Marie-Claire Alain, organ, Ensemble Vocal Stéphane Caillat and the Orchestre Jean-François Paillard.
By the early 1980s Frémaux had recorded over fifty works, winning a special citation from the Koussevitsky Jury for the 'Nottuni ed Alba' and Second Symphony of John McCabe. Other recordings include Berlioz (Grande Messe des Morts, Symphonie Fantastique), Bizet (Symphony in C, Roma), Delalande (Psalms 12 and 144), Fauré (Requiem), Ibert (Bacchanale, Bostoniana, Louisville Concerto, Divertissement), Poulenc (Gloria, Piano Concerto), Saint-Saëns (Symphony No 3, works for cello and orchestra) and Walton (Gloria, Te Deum, Façade, The Wise Virgins).[2] He also conducted the London Symphony Orchestra in the Symphonie Fantastique (1988) and a Ravel programme of Daphnis et Chloé Suite No. 2, La Valse, the complete ballet Ma Mère l'Oye and Boléro (1989).