Dear Michael,

I discovered your website only a couple of days ago, and it’s already starting to become one of my favorites on vocal technique. Keep up the great work!

One thing that has always puzzled me (and to some degree still does), is the subject of vocal registers and the ambiguous terminology used by different people. I’ve spent quite some time searching the web for information on this topic, and found that it basically falls into two categories.

The first would be scientific information, coming mostly from speech scientists, which is accurate in terms of physiology and acoustics, but lacks the connection to the art of singing (e.g. how different registers feel and sound in different voice types). The “application factor” is missing.

The other type of information, typically from vocal instructors, is “application only” but completely neglects the science behind it and thus fails to make the connection to the correct physiological and acoustic phenomena.

So it would be great if you added a thorough discussion on vocal registers to your website. I know that for myself (and probably a lot of other singers), the different definitions of head voice, mixed voice, and falsetto are especially confusing. Discussing these terms in particular would be very helpful.

As for “non-scientific” information, I’m not sure which school to buy into. For myself, I have adopted the idea of dividing the modal (or full, connected) register into chest and head voice, based on either dominance of thyroarytenoid (chest voice) or cricothyroid (head voice) muscles. So each “voice” is a set of many different TA/CT configurations. The falsetto register is detached or disconnected from the modal register and uses only CT muscles, leaving the TA completely slack, using only minimal vibrating mass and thus being airy and lacking overtones. I think that this definition is in line with the classical approach to the tenor voice, although some may use the term head voice to refer to my definition of falsetto, and call the “full” head voice, full or robust, or voce piena in testa.

Being a tenor myself (or at least having been classified as one), I am curious to learn about the ways to access the connected head voice, which is the full and big sound I associate with male operatic tenors singing above the second passaggio (e.g. the sustained A4 in Nessun Dorma). This has always been a challenge for me, it seems to be a non-intuitive coordination and only slowly am I starting to get a grasp of it. If you added information on this topic to your website, that would be great as well. I think there are a lot of tenors out there who have somehow mastered the first passaggio but are stuck at the second, not being able to release into their upper head voice and add strength and beauty to their top notes.


Thanks for writing. It’s good to hear that you have found my information useful.

I can certainly empathize with your question. The concept of registers can be the most important thing we learn. Unfortunately, there are many different descriptions of them. Which can make figuring things out difficult.

The ideas you describe are basically accurate. I define falsetto in a slightly different way. But I don’t bother using scientific terms. (I would call a light high voice sound that is still a true vibration “pure head voice”) For me falsetto is the attempt at pure head voice with a lack of necessary balanced muscular activity. If you were to increase air pressure in an attempt at full voice falsetto would break.

Actually, for me falsetto can happen in any register. So it isn’t really a register but a condition, one of a lack of proper register activity. I don’t know if science would recognize my definition. But I can demonstrate it and show how it fits with other conditions of registration, so it works for me.

I guess in a way I approach things in a combination of the two that you describe. I always look at things based on how they actually function. Which is part science, since we are dealing with the physiological mechanism. But it isn’t important to me to think in terms of the names we read in the books.

For me it is enough to recognize that there is some kind of adjustment that happens when we cross the transition around the top of the staff. This is all we really need to know so we don’t avoid the change that needs to happen.

But the reason this is important isn’t so much because we need to “do” the change, it’s so we allow it to happen. What we need to do is keep the mechanism stable as we rise in pitch. If we don’t do this then the mechanism won’t be able to function correctly and the change won’t happen.

The thing is, I don’t really think about the science anymore. It might tell us what happened, but it doesn’t tell us what to do. Science looks at things after the fact, behavior and function are looking at things as they happen.

Another aspect that I want to avoid with the science-based approach is the fixation with terms and names of muscles and ligaments and cartilages. We don’t experience names, we experience conditions.

So it doesn’t do us much good to think of the TA/CT relationship other than to give us some kind of context. But we certainly don’t deliberately adjust this ratio.

We experience our voice through sensation. We have sensation of muscular activity, we have sensation of vibrations and resonance and we have sensations of the character of the sounds coming out of the instrument.

All of these are part of our experience and contribute to how we coordinate the instrument. So from a certain perspective the way I work could be called scientific because we are concerning ourselves only with what is actually happening in the instrument versus images that try to influence the result.

I have called it the science of reality. In contrast to the science of books. The difference is in the science of books all voices are the same. It is true that all voices have the same muscles and cartilages, but that doesn’t take into consideration the unique condition each voice is in. The history of how the voice has been used, habitual tensions or lack of muscular activity. The one-size-fits-all scientific approach can’t really consider that.

What matters isn’t what each part is, what matters is the relationship between those parts. So even if we assume that the science-based explanation is accurate, it is describing the mechanical pieces and not the way we stimulate that machinery.

And stimulation is the real answer to our problems. Learning how to simulate the natural responses of the vocal mechanism is essentially behavior modification. So voice training more accurately falls into that scientific field than voice science. I suppose it would be most accurate to consider it a combination of the two.

So I guess the key idea to take away is the most important thing for us to do is keep the structural integrity of the instrument as we ascend the scale. If we do this we will allow the voice to behave naturally, which means at some point around the top of the staff it will alter to a smaller vibration. If we avoid the change we will break the structural integrity of the instrument in order to force the lower voice higher.

The best way I have found to develop this is to exercise it on longer arpeggios (like 1-3-5-8-10) starting full on the bottom and diminuendo towards the top. This allows the vibration of the voice to diminish as it ascends the scale, which is what registration is. (Just the vibration gets smaller, the resonance actually gets bigger)

If we don’t allow the voice to diminish we will just be staying in the current register, which will require effort to get into the high range. This is why I don’t recommend supporting more as we ascend. At least at first while the coordination is being learned. Because if we just support more we are likely to be just forcing the lower voice higher.

It is important to recognize the relationship between air pressure (support) and the vibration (registration). The more air pressure there is the bigger the vibration. What this means is if we support more as we go up, or crescendo, the vibration will stay big.

This is why I recommend we decrease intensity/air pressure as we ascend so we allow the vibration to get smaller. At least at first so we can develop the coordination. Then when we have this down so it is familiar we can keep the air pressure higher and still coordinate the shrinking of the vibration. This is then the full intensity high voice with the proper adjustment rather than the forced lower voice.

There is actually a sensation of an increase of air pressure inside us because as the vibration gets smaller less air is releasing with each vibration. So it feels like the air has to stop and wait its turn to get out. A little like a backup when a drain is clogged.

The specific details of how to actually do this obviously can’t be communicated through writing. We pretty much need to be guided through this process. But hopefully this gives you a little more clarity on what we are after.

Thanks again for your interest. Please let me know if this makes sense for you.