This most likely means you are singing the low end (normally vocalis dominant) without any balancing muscular activity from the CT and vice versa for the top. This is common of coloraturas of your age who have easy high notes that have not been balanced yet. The fact that you can get to the top easily probably means it is a little fluty. Many professionals get away with this kind of sound, so it is difficult these days to know that it is incomplete. The usable range requires an ever-changing balance between the two main muscle groups and when the balance is off (like singing a fluty top or a too chesty low) then one part of the range is lost for the sake of the other. There must be some chest in the high range and some head in the low range (simplification). When a balance is reached the quality of the sound is homogeneous from low to high. That balance is also responsible for the squillo in part. Develop full high notes over time so that the low is not lost and develop buoyant low notes as not to lose the top.
TS
Be not the slave of your own past. Plunge into the sublime seas, dive deep and swim far, so you shall come back with self-respect, with new power, with an advanced experience that shall explain and overlook the old.
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