Question: How does a vocalist raise or lower the pitch?
When I was a university student, I learned how my voice works in “vocal pedagogy” class. The most basic of functions is simply changing the pitch, so of course that was a big part of the first week of class. Like you, I was taught that to raise the pitch, my vocal folds need to stretch, and that it makes them vibrate faster. The problem with this answer is that it is not always true. For many classical singers, especially tenors, basses, and baritones, stretching the vocal folds to raise the pitch is the wrong answer 90% of the time. For other tenors, basses, and baritones, it’s the RIGHT answer almost 100% of the time.
So is there another way to change the pitch? Actually there are two more ways to change the pitch. The first one is called partial vibration. In partial vibration, a section of the vocal folds is prevented from participating, which causes the remaining section to behave as if the vocal folds are shorter to begin with, which causes them to vibrate faster.
The next method, the one you should be interested in if you want to make more robust “old school” sounds, doesn’t work like either of these first two methods. It involves putting tension on the vocal folds while RESISTING any stretching, and increasing breath pressure. This, like stretching the folds, increases the rate of vibration, which raises the pitch.
You can also mix these methods to get results that are somewhere in between. But any time you stretch the folds, keep in mind that the sound will be lighter, and you will use more air. Keeping them as short as possible and using a metallic sound will do the opposite: the volume will increase dramatically, but airflow drops to almost nothing. The effect can be a strange experience, and it led the “old school” singers to refer to it as “inalare la voce”. Authors like Manuel Garcia mention using a candle to help learn. In “Hints on Singing” he describes a “veiled” timbre and a “clear and ringing” timbre, and he points out that the clear and ringing sound “does not stir the flame”.
When a singer keeps the vocal folds short and tunes the vocal tract in a particular way, it can cause a nonlinear interaction (a feedback loop) that explains why this situation can feel “effortless” (but is actually the result of targeted effort). Although classical pedagogy is unable to discuss these qualities efficiently, it is possible to learn what they are and how they work by consulting the Complete Vocal Institute’s published descriptions. The name they have given to the vocal characteristic that classical singers associate with “chest voice” is “metal”, and the relative thickening or thinning of the vocal folds is called “density”.
If you’re trying to make a lighter sound, but still metallic, you’ll need to mix some stretch, some resistance, and adjust pressure to get the right pitch. If you want to make non-metallic sounds, that are very light, you’ll probably be stretching them a lot more, but maybe not depending on how much density you want (in either case, don’t expect to sing Puccini arias with a full orchestra like that). And finally, if you’ve attacked a note with short vocal folds and you want to gradually lower the volume but keep the same vocal mode, you will have to stretch the folds more as you decrease breath pressure. Back off the pressure without stretching the folds, and you will get quieter, but with a completely different character, and/or you’ll lose the pitch.
That which takes many pages of imagery and subjective description to express in an article about Franco Corelli or Enrico Caruso, can be said by someone conversant in Complete Vocal Technique using only three words: fuller density metallic.