Maag was the student of a true Ravel-admirer such as Ernest Ansermet, and his recordings by RAI reflect his exceptional feel for this music. In the 1950's and 1960's, RAI organised great concerts with all of the most important soloists and conductors performing at the time. The Diptychon of the two small Ravel-operas was entrusted to Maag, who at the time could already look back on an extensive collaboration with the orchestras of the Italian broadcasting company. The chorale of singers included the best which French opera had to offer at the time...

Two events occurred which were truly unique and became unrepeatable due to the combination of this stroke of good fortune. Voices were included which at the time were already well-known from Ravel's music, such as Michel Sénéchal, Colette Herzog and Philippe Mollet; furthermore, there were other singers who stood at the beginning of a brilliant career, such as Mady Mesplé (in three parts of Enfant et les Sortilèges) as well as Eric Tappy (Gonzalve in L’Heure espagnole); and there were voices who had arisen through the world of French opera like a comet, such as Andrée Aubery Luchini, who at that particular moment fitted into their parts perfectly.

That the Italian radio placed great importance on these recordings is reflected by the fact that a special stereophonic recording technique was used both for L’Heure espagnole in Turin, as well as for L’enfant et les Sortilèges in Rome. Particularly in Turin, new tape machines and tube-microphones were tested on this occasion, which, after restoration of the original tape, presented quite surprising sonic results for a recording of that time. No listener would believe this recording is 40 years old! The recording is without a doubt one of the most beautiful and accomplished.