- Gerhard Pechner, Richard Holm, Clifford Harvuot, Joseph Folmer, The Metropolitan Opera Orchestra, Josef Greindl, Osie Hawkins, Lawrence Davidson, Algerd Brazis, Hertha Glaz, Hans Hopf, Thomas Hayward, Emery Darcy, Lorenzo Alvary, Mack Harrell, Alessio De Paolis, Paul Schöffler, Victoria de los Ángeles
- Hans Clemens, Giovanni Martinelli, Charles Kullman, Risë Stevens, Francesco Valentino, Beniamino Gigli, Kirsten Flagstad, Eleanor Steber, Friedrich Schorr, Elisabeth Rethberg, Charlotte Boerner, Raoul Jobin, Lorenzo Alvary, Lotte Lehmann, Mack Harrell, Licia Albanese, Nadine Conner