Why would there be secrets? Seriously. There are no secrets but there are things which are worse. There are myths about singing. They have been around for over a century, some of them. The bad thing about myths is that they are either worthless or possibly very harmful. The other thing about myths is that they are assumed to be true but have never been examined by those who use them to mislead singers (usually unknowingly).
There was a time in medical history that doctors believed that "bleeding" or "bloodletting" a person would help the person to get well or to get better. The practice could have caused infections or worse. This went on for two thousand years, so it is not unreasonable to assume that myths have a long survival rate.
Science will usually reveal myths--eventually.
The first secret to better singing is to see if you are holding on to any myths regarding singing. The most common, if not the most ubiquitous is that a singer should "sing from the diaphragm". This implies that your diaphragm is actively doing something as you sing. This is where we first step out of the looking glass of wonderland. Check the sources of authority and licensed practice, specifically a physician, rather than most singing or music teachers who never had to study basic anatomy. Since the 1700s, doctors have known some specific facts about the diaphragm:
1) It contracts downward, causing the lungs to draw in air.
2) It cannot be felt because it has no proprioceptive nerves in it. Your hand has proprioceptive nerves, meaning you can feel what position it is in and directly can control it.
3) The diaphragm is in a state of relaxation when you are singing a tone.
4) If you push out the air, you are using muscles of the abdomen and the chest.
Remember that doctors have known this since the 1700s. Somehow they do not laugh at people for spewing useless misinformation. Most singing teachers who tell you to sing from the diaphragm do not know where it is, how it is shaped, or its actual function. If you wish, ask the teacher to draw the diaphragm and to describe its function.
What other common myths are there? That you can place your tone somewhere: your sinuses, your eyes, on the floor, in your face, your forehead, etc. This is a myth. You cannot make the sound go in a special place in your head. There are no secret valves in your head to direct the air and you cannot will it to go somewhere anymore than you can teleport an object across a room by simply thinking it into action.
Myths do not solve anything or help you to sing better.
Some people say, "Do not sing from your throat." or "You are singing from your throat." This is usually followed by their patting their stomachs and saying, "sing from here!" WHAT?! Let's get real. Where are the vocal folds (used to be called vocal cords)? They are in your throat. We could say that the teacher doesn't literally mean to not sing from the throat. If that is true, then why not say what you do mean? What is the singing teacher looking for? A freer tone? A bigger sound? Instructing to not sing from the throat yields no change, no results. There are ways to get a bigger sound and a freer tone.
Some teachers pat the stomach and say," Fill up down here." Once again this is a blatant revelation of ignorance of the human anatomy. If a teacher truly cared about the students, wouldn't it make sense to crack open an anatomy book, such as the old reliable, Gray's Anatomy? It has some excellent drawings and clearly worded information about the lungs and about breathing, including the function of the diaphragm. Your lungs do not extend into your abdomen. They end around the bottom of your ribcage. The only way to fill up the abdomen is to eat something and it won't be mostly air that you eat.
Muscles work the "voice" mechanism and they are controlled by your mind.
Does that seem true? That is something which can be verified by any good ENT (ear, nose, and throat doctor). The great news is that there are some singing teachers and vocal coaches who do know and understand the function of the singing voice and can give a singer exercises which work specific muscles for strength, control, and coordination. The physical technique of singing is not the complete solution to being a great singer, though. There is more. You can read about it here.
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