Question 1: Are you afraid of your chest voice?
Question 2: Are you afraid of your lower break (passagio)?
There are times I find when I have trouble getting good, rich chest tones, and those times are usually when I'm afraid of that sensation I feel when I make the transition over the lower "break". So instead of getting into full chest, I find myself "waffling", trying to bring head voice down farther than it can really go, and the result is a very pallid, uninteresting, "pure" low note that has no depth, warmth, or carrying power.
The opposite problem occurs sometimes when I find that I've "plummeted" into chest - and the resulting sound is loud and harsh to my ears. I've discovered that this occurs when I not only go into chest rather suddenly, but also unconsciously "cover" the chest note - the way I can tell I'm doing this is that I feel the resonance almost entirely in the back of my mouth and throat. If, by contrast, I go into full chest but concentrate on resonating the sound forward, I feel some of that vibration under my hard palate and even in my front teeth. It's certainly easy enough to adjust the placement - usually the "covered" placement happens if I let the back of my tongue drop too much, so it's almost like it's being pulled down into the throat, rather than keeping the back of the tongue up and "facing forward" (it doesn't literally face forward - that's just the image I use to keep it from pulling down too much).
Mainly, I remember that just because the resonating pharynx changes between middle and chest (from oral to laryngeal), the tongue position should not change, nor should the idea of placement.
Also, it helps greatly to keep the vowels very slim and as closed as possible (this means narrowing the mouth opening and keeping the back of the tongue "up", as I've described). It's particularly important on the "dark" vowel sounds - a and o and uh - to keep the vowels narrow and focused as you move into chest register. Not only will keeping the vowels narrow and "forward placed" help brighten the chest sound, it will also help minimise the obviousness of the lower "break" when you make the transition from lower middle register (voix mixte) to pure chest.
Hope some or all of these ideas help.
KM === On Neil Shicoff - http://www.radix.net/~dalila/shicoff/shicoff.html On yours truly - http://www.radix.net/~dalila/index.html
+-------------------------------------------------------+ | For what is your life? It is even a vapour, that | | appeareth for a little time, and then vanisheth away. | | - James 4:14 | +-------------------------------------------------------+
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