Voice science can make your voice go BOOM!

Voice science for singers

Those of you who are interested in voice science may have heard of the terms ‘harmonic’ and ‘formant’ before. These guys are making a bit of a name for themselves, and so we want to give you a basic outline of what they mean and why on earth you, as a singer, might want to get to know them.

From the outset we want to warn you that this is likely to get a bit heavy. It’s tricky to explain a complex subject like formants without an understanding of the other complex words we use to actually explain it. For that reason, we’re going to break this down piece by piece.

In every walk of life, increasing the understanding of the ‘how’ and ‘why’ we do things will helps us to figure out the best ways to do them. Singing is a deceivingly complex skill, influenced by the laws of physics, so this is where the scientific stuff comes in. In the past, singing has had a whimsical aura attached to it. Some think of it as magical unexplained energy that emanates from the human body. The problem with unexplained theories is that there is little guidance or measurement for creating excellence…and we all want to be excellent, right?

For centuries teachers have guided students based on their own personal experiences, feelings, and beliefs in how it works for them. Although this has some value, by understanding the mechanical and acoustical workings of the voice, singers, and their teachers, can start to identify some logical tools and clear actions to help voices develop.

Who really needs to know this stuff?

We admit it is a certain “type” of person who actually enjoys voice science. It can get quite, um, confusing. But any person can be gleeful at the result of a good adjustment even if it is scientifically-based. So, as we see it, this means this subject is for everyone! However, the folks who are going to find applying this subject particularly beneficial are the more advanced singers and the teachers of singing.

The Advanced Singer

Picture this…

You have been singing seriously for quite a few years, say 5 or more years. You have had some singing lessons, know your voice, and picked up some decent tips along the way. Your range is pretty good, and you can deal with most things without wearing your voice out like you did at the start. Maybe you are a professional, singing well with a lot of training in a particular technique? Either way, you have come far in your singing but still desire something more. More power, more ease, more stamina, more punch all round! If this is you, then understanding formants and harmonics could be your saviour. You see, it takes a sensitive and controlled vocalist to get the most out of this approach. Because you’re only a whisker away from the big hitter it takes only a tiny adjustment to get where you need to be. That’s where experience is crucial, and a familiarity with your vocal anatomy is also extremely beneficial.

The Vocal Coach

I know this is probably obvious, but singing teachers need some background in this subject to make the best decisions for their students. Formants and harmonics are at the very root of singing.

They are all or largely responsible for:

• Tone and power
• Why singers crack, flip, or can’t transition
• Range development
• Stamina
• Reducing strain and vocal damage

There’s probably more. But, the above is any singer’s wish list, right? So if you are a coach, it’s your duty to understand voice science a little deeper. It can, and will, help get you to the bottom of an issue more rapidly. And this is great for both student and teacher, i.e., they will be elated, and your reputation will be stellar!

Imagine a world where your singing is ridiculously easy, where it feels like the less effort you make, the more output you get, where you can just adjust your lip slightly, or edge your tongue forward and BOOM! The people in the front row are picking their faces up off the floor. Need I say more? Anyway, on to the meaty stuff!

Acoustic energy, sound waves, and vowels. Pardon?

In order to dig into voice science, it’s worth outlining a few simple things first. As singers, we are constantly making lots of different noises. We do this by, firstly, releasing air through our vocal folds. The clever bit is that as this air passes through the vocal folds it’s converted into acoustic energy, in other words, a ‘sound wave’.

The main way that we alter the noises is by changing the way this sound wave behaves once it enters the vocal tract. Quite simply we can do this by moving our lips, tongue, jaw, and larynx into different positions. This alters the space in our mouth and throat. The sound wave then bounces around in this new space resulting in a new noise emanating from our mouth. Cool, huh? In society, we have named some of these resulting noises: ‘vowels’. Try it yourself! Say ‘AA’ (as in the word ‘cat’) quickly followed by ‘OO’ (as in the word ‘food’), and notice how much your lips, tongue, jaw, and larynx move to change the vowels. (To feel the larynx find your Adams Apple)

A Pitch Went To A Party

We can change the actual vowel, and it’s tone and colour, by making silly faces, but this leads us to the question: what is a sound wave and how can we use that information to help us sing? This is when we introduce our good friends ‘formant’ and ‘harmonic’.

Scientists have worked out that the sound waves that knock about in our mouth and throat are quite complex. Although not visible there is a lot of information contained in every vowel we hear.

In case you didn’t know, clever people measure the pitches we sing by how many times the vocal folds vibrate per second. Just for example a ‘high’ C (C5) is produced by the vocal folds vibrating 523.25 times per second or 523.25 Hz. Hz is short for Hertz, after German physicist Heinrich Hertz. This pitch-determining frequency is also known as the fundamental frequency (F0).

Now things begin to get crazy. It’s not just the energy from the high C that we hear when the note is sung out. According to the scientists and researchers that study this, within each vowel sound wave there are ‘extra’ sound waves produced. These are called ‘harmonics’. These harmonics actually have the power to change the sound that comes out of our mouth! Yes, that’s right, the pitch is still high C but the strongest harmonics in the pack will dictate the tone and quality of the vowel that is sung.

We like to compare this to the times when we were at school and we held a house party. There was normally one girl that we’d have our eye on and we’d obviously pick her to come to the party! We’ll call her ‘Fundamental’ for the purposes of this article. ‘Fundamental’ was kinda ‘Fun’, but not so ‘mental’. She was actually pretty quiet. However, she would always turn up with her crazy friends (the ‘Harmonics’) to every party. The great thing was that, even though she was the leader of the group, some of her ‘Harmonics’ were louder and funnier than she was. This got the group noticed and labeled as ‘The Mental Bunch’! Even though Miss ‘Fundamental’ was quite timid, the perception of her group as a whole raised her reputation to being rather loud and brash, boosting her visibility at the party, when without her friends she would normally go unnoticed! So, harmonics can help to boost the fundamental sound wave as a whole and give it more energy.

Harmonics are best shown in a spectrogram. A spectrogram is a graph that scientists use to analyse and display harmonics easily. The peaks are the harmonics within the sound wave and the first peak is the pitch being sung:

You can choose harmonics

We spoke earlier about controlling the sound wave with our throat and mouth shape. Now that we have outlined what harmonics are, we can tell you that certain harmonics respond better in particular mouth and throat postures. Certain harmonics will be boosted or reduced depending on the shape of the vocal tract, i.e. mouth and throat. In turn this will have a positive or negative effect on the sound produced. The resonance of the vocal tract can also be measured as a frequency (Hz). This type of resonance is known in scientific circles as a formant.

If we go back to our house party analogy, it’s the same as saying that all the friends at the party became more excitable, louder, quieter or dull (aka formants) depending on which size room (aka vocal tract) they were in. If the room was too big or small it would ruin the atmosphere and the party would quickly fizzle out. Just the right size however, and the party went OFF THE HOOK!

One of our jobs as singers is to try and find the most responsive throat and mouth shapes (formants/room sizes/etc.) to boost the most influential harmonics and give us the most exciting sound and expressions. If we find these places, we have lined up harmonics with formants = party time!!

The Practical Stuff

Now that we have seen how much fun can go on in our vocal tract, we can try and put it into practice on the high notes. Let’s start with the larynx, because it’s this piece of cartilage that can influence our throat size the most. We have to be in control of it and maintain a generally neutral larynx position during the higher notes. At the very least we need to have the ability to adjust tone or larynx position when going into the middle and upper range. If you happen to be someone who strains (yells) when you sing, then this will be something you need to sort out before you can fully maximise the formant/harmonic relationship. Strain or lack of tone control indicate we are not in control of the larynx. If it is moving around or in the wrong position this interferes with the size of the throat and mouth ‘rooms’ too much.

Presuming your larynx is mostly under your control, it’s time to think of a vowel will to keep it neutral and shape your vocal tract to be ready for a party. That vowel is…UH (as in ‘mum’).

Aside from getting the larynx into an optimal position that will excite any harmonics that are in our 1st formant (throat room), the UH vowel also has another useful property.

So, we’re back at the party. All of the most excited harmonics are having a great time in the first room (throat). It’s just the right size to boost their energy. But there comes a time when the party must move to another room to maintain their excitement. This time is known as the ‘passaggio’, or the change in register at the top of chest voice (male Eb4/E4 – G4, female Ab4/A4 – C5). This new, smaller room is the second formant (the mouth). At the right time, certain harmonics need to move smoothly between rooms or they will lose their energy and fall asleep. The correct shaping of the vocal tract and hence the vowel helps to create an open doorway to the next room. This allows the harmonics to pass through easily and keep on jiving until the high C. The UH vowel is one which creates a natural doorway. It is used frequently in singing by voice teachers and singers who understand this concept for all genres.

The Man Himself – Pavarotti

The idea is to blend these vowels into everything. An element of these vowels shapes everything we sing and gives every lyric a shade of that vowel shape and tone. Take UH for example, and listen to Pavarotti in Nessun Dorma. It’s easy to use opera singers because they sing on top of these vowels really clearly, and in this case Pavarotti sounds like he’s singing everything with a shade of UH compared to the actual pronunciation. See our video for a comparison. Now take someone completely different… Whitney Houston. Whether consciously or not, she’s singing the chorus of I Will Always Love You, particularly the vowel AH from the lyric ‘I’, on an ‘UH’ sound. It’s subtler in contemporary music, but it’s the same principle. Check out the video for a comparison.

Once you have got the hang of allowing harmonics to move between formants at the passaggio and your larynx is stable in the UH position, you can then play around with the mouth and tongue to get the most out of the harmonics that are now present in the mouth. Typically through the first few notes of the passaggio we need to start to lower the jaw. The lips can’t be too wide or we’ll disrupt the boost. However, when we’re coming out the other side of the transition, the mouth can be opened more and the tongue can come further forward with each step up. This is how we can continue to tune in to the harmonics, making sure they still carry the most energy possible by shaping the rooms they’re in. If we do this effectively then hey presto! We have great presence of voice with minimal effort. Your vocal system will support itself through aerodynamics and resonance, making it sound like a breeze. If you want to alter the tone, however, you can either close the lips a little more for a darker sound, or widen them for a brighter sound. Very experienced singers can choose different larynx and tongue positions giving them a type of EQ control of their tone.

Confused still?

We are hoping you know a little bit more about formants and harmonics, but you may be asking, “what can I do with all this voice science?”.

Aside from flaunting your new found knowledge amongst friends, we believe that this knowledge could help you in your next practice. You will be able to consider the manipulation of the vocal tract and vowels to help you take your voice to that next level. Although the art of singing is, for most contemporary singers, intuitive, these considerations can act as a guide when vocalising. Ask questions such as, “What is my mouth doing on this pitch?”, “Why is my tongue so far forward?”, and “Why does this shape sound and feel like that?”. These are questions great teachers have been asking for years. You can begin to embrace them too, either with help from a knowledgeable teacher or by experimenting with your own vocal tract shapes and the UH vowel.

Our good friend and vocal coach, Ryan Luchuck, has been studying with world-renowned voice scientist, Dr Ingo Titze. He is very clear on the power of this knowledge telling us, “If you are a singer, understanding formants and harmonics not only instills confidence in your training approach, it empowers by allowing you to precisely fine-tune problem spots with confidence. Teachers owe it to their students (and themselves) to understand the voice as much as possible. I can’t overemphasize how much it’s helped in my voice studio!”.


Chris Johnson and Steve Giles are both experienced vocal coaches working in Southampton and London. They are with the Vocology In Practice teacher network and specialise in training clients in advanced vocal technique, style and improvisation. They are co-founders and presenters of the popular iTunes singer’s interest podcast The Naked Vocalist. As well as coaching and podcasting they are also in-demand performers and manage their own successful soul acts.