- Alessandro Bonci, Giuseppe Anselmi, Lina Cavalieri, John McCormack, Rosa Ponselle, Giovanni Zentella, Maria Sammarca, Ferdinand Ansseaau, Mattia Battistini, Claudia Muzio, Enrico Caruso, Elisabeth Rethberg, Richard Tauber, Rosa Raisa, Aureliano Pertile, Emmy Destinn, Alfred Piccaver, Florence Easton, Antonio Cortis, Dmitri Smirnov, Anne Roselle & Giovanni Martinelli
- Giacomo Lauri-Volpi, The Metropolitan Opera, Professori d'Orchestra Del Teatro Alla Scala, Grande Orchestra, Rosario Bourdon, Giulio Setti & Franco Ghione\Mario Cordone
- San Francisco Opera & Gaetano Merola
- Bertil Alstergård, Stockholm Royal Opera Orchestra, Erik Saeden, Kerstin Meyer, Stockholm Royal Opera Chorus, Sture Ingebretzen, Herbert Sandberg, Hjordis Schymberg, Jussi Björling, Hugo Hasslo, Olle Sivall & Ingeborg Kjellgren
- NBC Symphony Orchestra, Robert Merrill, Arturo Toscanini, Arthur Newman, Johanne Morland, Maxine Stellman, John Garris, Paul Dennis, Licia Albanese, George Cehanovsky & Jan Peerce
- Beniamino Gigli, Franco Ghione, Lawrence Collingwood, Umberto Berretoni, Tullio Serafin, Orchestra of the Rome Opera House, Orchestra del Teatro alla Scala di Milano, Crino Bechi, Ugo Novelli, Tancredi Pasero, Fedora Barbieri, Elda Riberri, Maria Caniglia & Ebe Stignani
- Aureliano Pertile, Tino Pattiera, Fernando De Lucia, Enrico Caruso, Tito Schipa, Giacomo Lauri-Volpi, Nino Piccaluga, Enzo De Muto Lomanto & Alessandro Bonci