The classic book is Lilli Lehmann. It's out of copyright, and there's a free copy off of project gutenberg (Get the one with images).
http://www.gutenberg.org/ebooks/19116
I'll warn you, it gets technical rather quickly, since her goal is a physiological, scientific explanation of "resonance" "placement" "open" "covered" "dark" "nasal" and all the other indefinite terms still generally used today. Her focus is on singing but the physiology is the same for speaking as well.
The first problem with improving your voice is that improving your bicep is easy --it's there on your arm, you can plainly see when it's flexed or not. All the muscles involved with singing are internal, hidden underneath bones, deep in the center of the body, and can't be seen. Is your palate lifted or not? Without an X-ray machine, you can't see. It's a process of learning all these hidden muscles deep within you, and it takes time to become aware of them, feel them, and consciously control them. Because just like any other muscle exercise, it's all done by feel.
The second problem is the very production of sound removes your ability to hear it. You're too in the middle of it, and the sounds from your mouth, nose, and nasal resonance cavity overwhelms your own ears ability to hear how it sounds from the outside. Is the palate lifted the right amount? Is the placement correct? Without someone listening to you from outside your head or using a tape recorder, you can't hear. You do learn how good voice feels. It sounds very different inside your body where you make it than it does outside where people hear it. You can not trust your own ears. Beginners who try to go by what sounds good to themself always end up with "internal focused head voice". All their voice gets focused at their own inner ear canal, and never leaves their head. They sound great to themselves. To everyone outside, they sound like they've got a permanent head cold.
Improving your voice will maybe make a 5% difference in your approach rate success. Plus it's fun. But don't procrastinate from doing approaches while you work on voice.
http://www.gutenberg.org/ebooks/19116
I'll warn you, it gets technical rather quickly, since her goal is a physiological, scientific explanation of "resonance" "placement" "open" "covered" "dark" "nasal" and all the other indefinite terms still generally used today. Her focus is on singing but the physiology is the same for speaking as well.
The first problem with improving your voice is that improving your bicep is easy --it's there on your arm, you can plainly see when it's flexed or not. All the muscles involved with singing are internal, hidden underneath bones, deep in the center of the body, and can't be seen. Is your palate lifted or not? Without an X-ray machine, you can't see. It's a process of learning all these hidden muscles deep within you, and it takes time to become aware of them, feel them, and consciously control them. Because just like any other muscle exercise, it's all done by feel.
The second problem is the very production of sound removes your ability to hear it. You're too in the middle of it, and the sounds from your mouth, nose, and nasal resonance cavity overwhelms your own ears ability to hear how it sounds from the outside. Is the palate lifted the right amount? Is the placement correct? Without someone listening to you from outside your head or using a tape recorder, you can't hear. You do learn how good voice feels. It sounds very different inside your body where you make it than it does outside where people hear it. You can not trust your own ears. Beginners who try to go by what sounds good to themself always end up with "internal focused head voice". All their voice gets focused at their own inner ear canal, and never leaves their head. They sound great to themselves. To everyone outside, they sound like they've got a permanent head cold.
Improving your voice will maybe make a 5% difference in your approach rate success. Plus it's fun. But don't procrastinate from doing approaches while you work on voice.
"Alpha children wear grey. They work much harder than we do, because they're so frightfully clever. I'm awfully glad I'm a Beta, because I don't work so hard. And then we are much better than the Gammas and Deltas. Gammas are stupid. They all wear green, and Delta children wear khaki. Oh no, I don't want to play with Delta children. And Epsilons are still worse. They're too stupid to be able to read or write. Besides they wear black, which is such a beastly color. I'm so glad I'm a Beta."
--Aldous Huxley, Brave New World