How does singing volume affect vocal range?

Question

I saw mentioned in passing in another answer:

As a rule, the more air you are forcing** through your throat, the higher (also louder) you can sing in a given register

I only recently noticed this myself, that higher notes sound fuller when I am "going for it" but hadn't realised this was because I was singing notes (say C4) in my chest voice when singing loudly, but head voice when singing more timidly.

How big an effect is this as a rule, and does it continue to become more significant the louder you get? Does it apply to head voice & falsetto as well as chest voice?

This is all in the context of singing higher notes, does volume also have any effect on your lower limit?

The term forcing here should be read in the physical sense NOT the musical sense i.e. straining. Air moving across/through the vocal chords makes them vibrate, if you have more air you get more volume. At least, that's the focus of my question. Please don't get side-tracked discussing "forced singing" because that is not what I'm discussing here, but changes in volume with good technique i.e. quiet singing versus singing with power and gusto.

Answer 1

Okay - so here is an answer to your edited question where you made it clear that you want to know about why you get more volume with more air and why it requires more air to hit the higher notes.

First let's talk about volume. As you know, the vocal chords produce sound by vibrating - much the same way as a guitar string does. Like a guitar string, the sound does not emanate entirely from the vocal chords but from all the resonators in the head and vocal tract. A guitar string vibrates the top (soundboard) which is were most of the sound comes from.

In order to cause the vocal chords (aka vocal folds) to vibrate, we must force (there's that word again but in a new context) air across them by exhaling. The process of forcing air across the vocal chords causes them to vibrate and using the muscles that control the vocal chords to change their shape, allows us to alter the pitch of the sound produced by air passing over our vocal chords.

In order to get more volume, it is necessary to increase the intensity of the vibration of the vocal chords. This requires a larger and more powerful burst of air to be passed across the vocal chords by exhaling more forcefully.

Again using the analogy of a guitar string, to get more volume you must pluck the string more forcefully to cause it to oscillate in a wider pattern. Plucking the string with more force does not change the note, only the volume.

Now to explain why more air is required to sing high notes - whether in head voice or falsetto. To sing higher notes, your vocal chords must be stretched tighter. Think of what happens as you tighten a guitar string. As you turn the tuning peg to tighten the string, the pitch continues to rise. This is because the tighter string will vibrate more rapidly - thus producing a higher frequency sound wave.

Vocal chords work similarly (tighter = faster vibration). Tighter vocal chords naturally will require more air pressure to cause them to vibrate because - well they are tighter. So to belt out the high notes, you must force a more powerful burst of air across the vocal chords than will be required to sing a lower note at the same volume.

... does it continue to become more significant the louder you get? Does it apply to head voice & falsetto as well as chest voice?

The main difference between chest/mixed/head voice and falsetto, is that in falsetto - the vocal folds are not pulled together so they are touching. So the air is more easily passed between the chords and that's why falsetto sounds more "breathy". It's also why you can hit the high notes in falsetto without quite as much air pressure.

However regarding singing high notes at a louder volume - since it requires a larger burst of air to both increase volume and vibrate the tighter vocal chords, it is difficult to sing high notes quietly - UNLESS you use falsetto. The larger burst of air required to vibrate the tighter vocal chords will simultaneously serve to increase the volume. That's why you see many professional singers pull away from the microphone when they are hitting the highest notes. They can't sing them at the same moderate volume as the midrange and lower notes. Thus hitting the highest notes in your non falsetto range may also require you to sing with maximum volume as well. Low notes can be sung with less volume using less air, but more air can be added to increase volume if desired.

Since falsetto involves passing air across vocal folds that are not tightly touching, it's easier to cause them to vibrate because you are not forcing air between vocal folds that are pulled together. So you can actually sing the high notes rather quietly when using falsetto. But you will notice that you won't be able to produce quite as much volume with falsetto.

Answer 2

I saw that too and have a problem with the term "forcing". FORCING air through your throat implies tension either in your throat or other parts of your body. I did not want any future visitors to the site to read that and get the wrong idea so I want to put this concept into a more proper perspective.

It does require more air being exhaled to sing high notes than low notes because the vocal chords are stretched tighter to sing higher notes (like stretching a rubber band). Tighter vocal chords require more air to vibrate them than looser ones.

But I believe it is better to discuss how to allow the body to more naturally and effortlessly push more air across your vocal chords instead of "forcing" air "through your throat".

You never want to tense your throat muscles in a way that constricts your throat at all and particularly don't want to tense them to the point where you feel you are needing to "force" air through your throat. Tightening or restricting the the throat is not required to tighten the vocal chords. Without going into a discourse on physiology, the lengthening and shortening of the vocal folds (aka vocal chords) is controlled by the cricothyroid muscle and thyroarytenoid muscle.

Breath support is a very important part of singing. Proper training to build the muscles that support the diaphragm and proper technique developed through specific vocal exercises and practice - will give you the ability to push more air across your vocal chords with less effort, force or tension.

I used to constrict my throat and force air through it in an attempt to hit the higher notes. Many singers have a tendency to do that in the mistaken belief that it helps tighten the vocal folds for the high notes. I found that I was straining and damaging my voice by doing this and losing some tone and control. I have learned that relaxing the throat while singing the high notes prevents damaging stress on my vocal chords and the rest of my body - and improves the quality of my singing.

I also notice that if I am singing in head voice or falsetto and constricting my throat, I have less volume. If I relax my throat to allow more air to flow across my vocal chords with less resistance from a constricted throat, the volume goes up. Try it yourself. Start singing a high note in falsetto while tightening your throat and then consciously relax your throat as you sustain the note and watch the volume increase.

With the proper vocal exercises, you can learn to tighten your vocal folds to sing high notes without straining or constricting your throat.

It is true that in order to increase volume produced by your voice at either end of your range, you will need to exhale a greater amount of air to pass across your vocal chords and into the resonators in your head. But this does not mean you should feel as if you are forcing anything.

Again the key is learning proper technique and developing better breath support to train and enable your body to push more air across your vocal chords with less effort. This is best accomplished with lessons or with a qualified vocal coach. There are also many good lessons for free on YouTube.

Answer 3

Yes and no. The more air you use, the louder you are, but falsetto and chest voice are two different techniques. More air means more volume when using proper singing technique and is required to make your voice sound full. The deeper you get, the more air you need. When going below your "natural range" to the deeper notes you can sing, your voice sounds very airy, but not necessarily loud. However, going up to falsetto requires little air and sounds very loud. But why?

Frequency is one possible answer. High frequencies are perceived louder than low frequencies by the human ear.

So in order to become louder when singing deep notes, more air is required. The deeper you get, the quieter you become, the more air you need. Singing loudly does not affect your range on the deepest notes, but it does in fact have a huge impact on high notes. High notes require a lot of pressure and your chest voice can be expanded to the top when "going all in".

When singing timidly, less air is used to sing and it can become very difficult to reach a high note with your chest-voice if the needed air is not given. However, when using falsetto (which is one of the techniques that requires the least air amount), singing timidly already provides the needed air, which makes it possible to sing.

Singing in general doesn't require a lot of air. More air does make your singing louder, but can make it sound bad, when used at the wrong place. A falsetto with too much air would sound very transparent and thin, as well as deep tones with only a little amount of air.

Forcing yourself into singing loudly is not always the best option. If you're singing in the middle of your range, the "the louder the better"-rule fully applies, high notes require the most power. But when rumbling very deep notes, loudness becomes very tricky due to the needed air and needs a lot of practice. Falsetto on the other hand is very loud with little effort, due to its high frequency.

Short answer to your question: Yes, more air means more volume, but the higher you go, the lesser air you need to go loud.