I can hardly make my warning against the voice producers strong enough…Each of them teaches his fad. Walk through the passages of fashionable teaching studios and listen to the exercises and the quality of tone you hear through the green baize doors. A walk in the Zoo is more soothing to the ear and mind.
You can make a list of pet fads: excessive nasal resonance, the placing of the tone in the mask, over-blowing and violent forcing, learning to sing like Caruso, low diaphragmatic breathing, sucking air quickly through the nose, bleating vowels, a three-inch tremolo, placing favourite notes in the head, no registers – as if a one stringed fiddle could ever be a success! If you open a green door you will be introduced to a thousand other little fancies, too numerous to mention…
…I cannot recall one singer who has devoted the best years of his student life only to voice production and has taken any position in the operatic or concert world. All these voice producers’ pupils sing off the pitch.
Wood, Sir Henry Joseph. The gentle art of singing. Oxford University Press, Humphrey Milford, 1930.