Francesco Lamperti (1811-1892) 

Practice breathing slowly at first, then quickly. Now see how nearly you can approach the yawn without yawning. Now, put your finger far back on the tongue to the point of gagging. This position of the mouth and throat is favorable to good tone by opening the throat in all directions. 

All these exercises practiced carefully in a strong whisper will be of great value in disciplining, strengthening and controlling the vocal organs, and if the emotions, feelings and expressions are practiced intelligently, they will enable you to assume any character, mood or expression desired at once, but each must be mastered separately. 

When we have acquired control of the breath, the next step is to open the back part of the mouth. Think of the singer's throne at the back and top of the pharynx and raise the soft palate and head muscles without effort, widen the whole pharynx.The very thought will do it. You will observe at once the change even in the speaking voice; always support the tone with balanced ease. 

This exercises will not only make a musical singing, speaking and reading voice, but it will banish clergyman's sore throat and many other forms of throat trouble, which come from wrong placing. Placing means simply adjusting, balancing all points with ease. If we open the back part of the mouth, the front will take care of itself. Take the Italian ah and aw broad, and be sure that you open  the throat, for you can say them without opening the throat. 

Open the throat as much as possible without fatigue or strain and you will be astonished at the volume of voice developed at once, without effort. 

In singing songs and operas, the attention must be given to expression and there is not time to think of a favorable position for the voice, but if you have acquired the habit of keeping the throat open it will adjust itself in according with natural law. The secret of rapid improvement in voice lies in mastering each particular essential, before taking up the next. 

We are supposed now to be building or restoring a voice, but the best voices will be improved by correct practice. If nature has given you a fine voice, well placed, then the right practice will give it expansion, and bring possibilities before you of which, perhaps, you have never dreamed. If your voice is small and thin, you can take comfort yourself with the knowledge that all things are brought about by condition and practice, and if you understand the laws of acoustics and the adjustment of the vocal apparatus, a small voice may be increased greatly in power and extent, and, what it lacks in power it may make up in intensity and sweetness for the softest tones, when controlled rightly, may be heard as distinctly as the loudest, and with far more pleasing effect. Intensity comes through control at the throne of the pharynx. 

—Student of Fransceso Lamperti, Manuel García, and Antonio Sangiovanni, c. 1890.