Curious to discover the activity of professional musicians, he escaped from the work of manufacturer of crates where his parents had sent him and managed to become second violin in a street orchestra.

He had to wait until 1834 to win the Grand Prix with L'Entrée en loge, a cantata composed on a text by Jean François Gail.

He presented an Ouverture on 20 October 1838, badly received by a skeptical jury and against possible innovations: the three voices of men on the second motif in E minor probably left a bitter taste.

Among his pupils were Louis-Aimé Maillart, Georges Bousquet [fr], Théodore Gouvy, Jean-Baptiste Weckerlin, Émile Prudent, Olivier Métra, Edmond Hocmelle, Adolphe Blanc, Albert Gisarn, Victor Frédéric Verrimst and Oscar Comettant who described him as "an ingenious and witty scholar".

In parallel with his classes, Antoine Elwart was a prolific composer: he wrote a Messe solennelle in 1838 for the baptism of the Comte de Paris (future pretender "Philippe VII"), and presented on 24 August.

It means knowing how to enjoy all kinds of styles, without renouncing the sincere and unprejudiced admiration which such and such a master, this or that virtuoso, with whom our organization makes us willingly enter into a community of ideas