Alexa: [00:00:00] What are we really talking about when we use the term tilt?

Well, for this episode, I'm joined by the wonderful voice researcher, Mathias Aaen to unpack the science behind thyroid tilt, exploring his latest studies, and what they reveal about pitch, physiology, vocal fold lengthening, and healthy singing.

We are talking about the common misconceptions of tilt; translating some of that research into studio ready language; and asking some of the big questions, from what the heck is tilt? To are our teaching prompts actually doing what we think they're doing physiologically?

So if you love a practical pedagogy grounded in science, then hang around for Mathias Aaen.

Mathias, welcome to the podcast. How are you doing? 

Mathias: I'm good. Thank you for having me. It's a pleasure. 

Alexa: As you sit there in lovely Copenhagen, how do you perceive scientific papers? You write them, so you are [00:01:00] obviously quite clever. 

Mathias: Thank you. That's very kind. 

Alexa: When you are writing them, how do you think singing teachers and people like me and the listeners will receive them and do you have any advice on how we can read some of these papers that we're gonna talk about a bit later and kind of really get our claws into them with good understanding?

Mathias: I think the first advice would be to be kind to yourself as a reader. If you haven't had formal training in the sciences or formal training in statistics or medical measurement types, I would say be kind. Read the things that make sense, the things you go, Hmm, what is that word? Throw it out, maybe not important.

And if it's important, go and check it out. You know, look it up, look it up. But in general, be kind, read through, get the gist of things. And mostly I would say the introductions are really cool 'cause you get this kind of layout of what's in the field. Then the methodology can be quite dense sometimes to get through in the papers.

But then you get results like kind, ooh, this is interesting. But a few bits and bobs of [00:02:00] statistics here and there. And then the discussion really tries to weave that together. So I think focusing on the introduction, getting things, you know, set up right. Then looking at the results and macro scheme of things.

And then the discussion really helps to weave that together hopefully. So we get that kind of, let's say we dive in without getting too deep into things necessarily. 

Alexa: Were you always interested in science? 

Mathias: Um, I think I've been interested in learning about how things function and how things work. Its components, the mechanisms of change.

I started off in a different part of, of the field not even related to voice at all, and then I always sang, so I got back to singing. And then I found having that curiosity, the natural instinct to want to dissect into the smaller components as well as the pedagogical kind of more sensitive or the more human touch is a really nice combination.

So these days I'm very fortunate to be working both in the institute but also in a hospital where we get to do both of those things.

Alexa: You are going to help us dissect this idea of tilt.

Anatomically [00:03:00] speaking, what does the term tilt usually reference, and physiologically what's actually moving in the body?

Mathias: So the term tilt usually refers to, at least in our work, a thyroid tilt. So that's the thyroid cartilage- it sits right here in the front if you're not that familiar with anatomy. And what happens when that tilts, it's a downwards and kind of forwards movement, um, of the thyroid cartilage towards the cricoid cartilage.

And because the vocal folds insert into the thyroid into what's called the anterior commisure, they get pulled upon when the cricothyroid muscle or CT muscle contracts, and that pulls the thyroid forwards and that lengthens the vocal folds. So we get this kind of tissue stretching or getting the, let's say, longer vocal folds all else in the vocal system being equal, which typically relates to getting higher notes or getting in this case, something along the lines of, of different weight in the sound. 

Alexa: Under observation, have you seen any particular tilt in any other directions?

Mathias: That's a fun [00:04:00] question.

So the larynx tends to want to move forth and back, but of course other structures can also move upon it by activations. I know that some like to think about, um, backwards tilting. Uh, we don't see much of that in our studies. Uh, we see more rotations or these kinds of of translations.

But the tilt specifically in this, um, what we're talking about today, two papers we're looking at today, those two papers deal with thyroid tilt only because we can really see that from above with the camera, nicely we see move movements happening. We can also see that from the side with MRI, for instance, so CT scans, allowing us to look at how structures are moving. And cartilages tend to look at that work quite easily.

Alexa: So just to get really into the nitty gritty, if we were all to observe now a singer's larynx during a tilting motion, what would we see happening and what are the surrounding structures doing?

Mathias: First of, let me say that there are many ways to observe a larynx move. Most of them, as you'll see in a lot of papers on singing do [00:05:00] what they're called nasalstroboscopy or laryngostroboscopy. These are cameras inserted through the nose and they go kind of down into the vocal tract hanging just below the, the nasal passage somewhere.

And you can kind of then see the structures from above. Um, it allows us to film the larynx with some flashing lights like in a club that looks like slow motion of the tissues, which is really nice. But there are many other ways of looking at the the larynx as well. We could use, for instance, MRI, CT, other types of medical imaging.

In the papers that we are talking about today, we used this kind of camera through the nose. That means we're looking at the larynx from above. And so when we see tilting of structures, it mainly looks like a kind of forward rocking of the larynx as if it shifts plane forward and kind of downwards at the front.

Um, and we see also stretching of the mucosa that are attached to it. Uh, and that means, for instance, increased distance between the arytenoids and the posterior pharyngeal wall and those mucosa are getting stretched out. It might be that we see if the larynx is open [00:06:00] enough, also vocal folds being lengthened or even stretched out a little bit.

But the camera's so close to the larynx and it sits in a way where we can't really reliably measure vocal fold length from this type of data. So while we do see it, uh, and we do see the, let's say the the structures moving, we can't really see the thyroid cartilage itself. We see the consequence of it moving. We can't really measure some of these distances because the camera really distorts the view. So we need, let's say, different methodologies to kind of observe this. So we've done our studies and these two papers are endoscopy based. We've also seen some of these motions on MRI and on CT.

Alexa: Your studies were based on the CVT methodology by Catherine Sadolin, which uses language like metal and modes and I think density as well.

Could you just define these for the non CVT trained listeners? 

Mathias: Yeah, of course. So the CVT framework, let's say, as a, as a whole, is a way to organize and categorize the sounds that the [00:07:00] human voice can make with teaching techniques to make these sounds in a healthy way. So it's a really huge framework with tons of possible sounds.

And the underlying principles to get to all those variations are these concepts of metal, density and what we call vocal modes. And metal is the kind of, let's say, sharp contour in the note. It's like a brassy or bright or brilliant percept we can hear. And we know from research that metal can be made all the way from 0% to none of it at all to 100% in a continuous scale.

Um, is produced by interactions between how the vocal folds are vibrating, creating certain narrowings in the vocal tract that favor specific resonances. And there some specific formant tuning patterns related to specific vowel choices. And we can think of singers like, uh, Pavarotti where he sings dramatic high notes they have this kind of ringy brassy feeling to them, or Whitney Houston, Jennifer Holiday, Tina Turner. When they sing these powerful, uh, loud notes, or even Maria Callas singing some of her [00:08:00] beautiful middle and low notes dramatically, they have this kind of directness or hardness or rawness to them. And of course we layer with other stylistic and genre choices, but that kind of note contour is always there.

I think we can play some examples of that. We can actually hear it. And I've got some examples with me so we can have a little check what that sounds like for those of you listening in.

So if we think something that's more metallic, somewhat more brassy or bright, something like, for instance, this sound...

really cool singing. Thank you Ella. Um, and if you take the same voice just to contrast that with uh, something that's non-metallic, something like this ..

You can hear that one of them is much more brassy or, let's say more direct, more [00:09:00] compact. One is much softer. Of course, also loudness differences and other things are changing. But just to give you the example in the same voice.

And the same thing can happen in the male voice. We can think about, for instance, um, Jonas Kaufman did a very nice example here of very soft classical singing...

um, and the same voice here. So you, Jonas Kaufman obviously doesn't sing always softly. So the same voice with more metal, we can hear the metallic brassiness.

Now, contrast that softer sound with [00:10:00] this more direct or compact sound...

 so it obviously it has more loudness, it's louder, but it's also a different kind of wanna say raw or direct or compact contour in there. That's what we call metal. And we can imagine that that goes in a, in one direction, like a horizontal direction.

Then density, the other term we used, is mapped in a vertical direction, so the other direction. And density refers to the perceived weightiness of the note or the filling in if you have like a, like a circle of filling in on the board, or the compactness of the sound, that also ranges from zero to a hundred percent with 0% being a falsetto or a kind of head voicey to use that term, uh, kind of sound. And a hundred percent density being the heaviest or the fullest we can produce.

And at least from what we know so far from our own studies and other studies from from around the world, the degree of density is based on the degree of forward thyroid [00:11:00] tilt with a minimal amount of thyroid tilt creating the least weighty or dense note we can think of. And the, the more we tilt the less density we get basically.

So you can think of singers like Bruno Mars or Peter Gabriel or Laura Fabian singing and many more, they sing in a way that's kind of held in or held back. That's a reduced density sound with more forward thyroid tilt. Could sound something like this in a male voice...

still soft is not metallic, right? So it's still soft, but it has a bit of holding back a little bit. If we now think about going on full density, so it has, let's say more weightiness to it, less thyroid tilt, at least assumed for now it sounds more like this.

This is still [00:12:00] soft, right? It's still not loud singing, but it has much more weightiness to it. So this, that's a different dimension than metal. It's not the loudness or the compact directness. It's more how weighty is the sound.

And we know that singers in genres like RnB or world music, or even female western operatic singing in the middle parts of their range will use this to kind of sing with less weight or to bridge between the lower, more fuller metallic sounding notes and the higher non-metallic sounding notes.

And we combine these two dimensions. So one is horizontal, one is vertical. We kind of get this map where we can form an overview, where we can place any note and a singer's technical choices or wishes that they might have by their amount of metal and the degree of density. For instance, we can say, I would like 80% metal as a hundred percent density. That would be a loud and powerful sound, right? It's bright, it's full feeling. We can think of those loud money notes and power palettes or rock singing. Or we could [00:13:00] choose to sing with 0% metal and 20% density. That's like a soft or held back sound that feels more intimate or close. Something like jazzy or poppy or female musical theater, we're wanting softer volumes.

And having these two dimensions gives us then the foundation of talking about vocal modes. So this is, let's say we layer on top of these the physiology dimensions of the vocal tract and the vocal behavior of the larynx, and how we form and tune or resonance tune. And we can think of the vocal modes as the easiest way to organize super efficient and super effective sounds in the voice.

We use that as a basis to explore more complex expressions from a healthy basis. And they are sometimes called, like, let's say, nickname the gears of the voice. And we'll talk about four neutral- non-metallic usually. Overdrive and edge- more metallic. And curbing let's say reduced metallic, so it's in the middle of them.

So, we can then use density or this idea of tilting on all of these to create even further [00:14:00] subdivisions or variations of them. That's what we looked into these studies is how do we look at this? What happens in the larynx? How can singers control these? And we can kind of think of the vocal modes as the basic setup, we can then play around with amount of tilt to change the density of them, and we can even call them differently by shaping the size of the vocal tract, we can add vocal effects to that, like audible air, vibrato, distortions. We do step by step, so that's the CVT let's say the, the fly in really easily is the density and metal as the perceptual things we can hear.

We know what they come from in physiology, but they are easy to pick up with our ears. And then we overlay that with resonance or formant tuning patterns or vowel shapes and specific laryngeal setups. And we use that as the basis to train a sound to then get to the expression in a fast and efficient way.

Alexa: And just so I understand and other people understand, and if they're coming from a different methodology or no methodology at all, is this referring to things like thick fold, thin fold, or chest voice, head voice, M1, M2, the kind of [00:15:00] buzzy versus the non-buzzy.

Is that kind of the same? It's just different language?

Mathias: I think that buzzy versus non-buzzy from Ian Howell's work is very closely related to metallic percept. When we talk about registration, that's a whole different beehive. Um, but we could say that, uh, density and metal are mainly variations within what we can call M1. Or chest if you wanna talk about that terminology, modal voice in speech and language, um, pathology.

Um, so the, these are all variations within that box of M1. They come with different vocal fold patterns or vibrate vibratory patterns. But they're really defined by a combination of vocal tract and vocal fold behavior, um, and vocal fold tension, vocal fold mass, uh, differences.

Um, so it's, it's a more nuanced way of looking at registration, for instance, or more nuanced way of looking at vocal function. I, I think the chest- head separation, for instance, is very dichotomous. It's either or typically. Um, and so looking at nuances within all of them requires then more language. [00:16:00] So these models really try to cut... It really tries to cut across this by saying, okay, what are the underlying dimensions we can look at and how do they then interact with, let's say, pitch for instance or volume or other choices we can make as singers?

Alexa: How would you compare the results from the study that came from that paper 'investigating laryngeal tilt on the same pitch phonation', and then the later study that resulted in the paper 'correlating degree of thyroid tilt independent of fundamental frequency control as a mechanism for phonatory density?'

Mathias: Those two studies really kind of tie as a pipeline from one to the other nicely. Um, the first one was the pilot? So it's a smaller study to explore these notions around mixed voice without opening up that can of worms. But the idea of, okay, what happens when we make these kinds of sounds? Um, and is there really only one mixed voice? And if there is what happens with these types of, of physiologies? Um, and that [00:17:00] first pilot was really interested in variations that we saw and heard in singers using or wanting sounds that required specificity towards this kind of weightiness dimension that we now call density.

And the study also responded to this vocal pedagogy idea that was going around that all vocal fold lengthening results in the higher pitch. This really did not correspond to what our data was looking like and what we saw in other studies from around the world.

And so we thought, Hmm , we should study this more systematically. And before we did that in a large scale, which costs a lot of money, we asked, okay, if we do it in the smaller pilot, we can see if it's even feasible. And if we do, what can we even see? So this pilot study found what appeared to be a forward thyroid tilt combined with the rotation actually of the arytenoid cartilages and that this movement that we saw related to sounds that we were perceived by listeners as having reduced density or having reduced weightiness.

Now, the second study was a much larger follow up, so we [00:18:00] took, instead of having just three people, we took 21 people. And so we had the same, let's say, methodology, the same idea, but now in a much bigger, uh, population, it's also much more diverse.

So we included singers from diverse training backgrounds, from different genres, different styles of varying sex and age characteristics. We also wanted a larger population to be able to look at some of the findings in a statistical way because the pilot, we just looked at what is there. We can't really do any statistics on that.

It's too small. Um, and we also wanted to build a systematic or scientifically valid and credible way of analyzing endoscopic data. 'cause when we took camera into someone's nose, we are looking at their larynxes. But that's really subjective looking at what's moving. It's dependent on the person looking at that image.

So we thought, hmm, is there a way to build a, a way of describing that that's actually scientific and gives you something you can analyze from ? So we did that as well. Um, and then we took all that data and we also combined it with perceptual [00:19:00] tests, uh, of can these sounds be heard, accurately. Do people agree on what they actually hear?

Because what good is it to know what something is moving in a particular way if we can't accurately hear it? Um, and that means if we can't hear, we can't use it in a teaching situation. So it has to kinda get that link as well established. So that paper really did all of that. So it's, it's quite big. Um, and what we found was that the only laryngeal gesture, the main significance statistically, um, between samples of more or less of this perceived density was the thyroid cartilage tilt for both the females and for the males.

We also found that there's more possible tilt in non-metallic sounds. So the sounds that have less of this ringy brassy feel, meaning sounds that most likely have a little less vocal fold contact or vocal fold adduction, little less firm adduction, which we can kind of assume means a little less thyroarytenoid or TA, muscle contraction.

Whereas in the sounds that are more metallic, so they have more of that antagonistic TA muscle [00:20:00] involved, we get a little less available CT contraction.

We also find that when singers use more tilt, they tended to lower the SPL. So the volume that they're trying to sing with, which we have both, we actually thought we didn't study we hypothesized in the paper that that relates to maintaining vocal health, that we do not want to increase subglottal pressure too high on tissue that are stretched, thereby have more tension.

We also looked at the perceptual tests. So could these 33 people actually hear what we would call density and nicely they had high accuracy so they could hear it. Um, and they also agreed on what they heard, which is really nice, meaning that the teachers were able to recognize correctly conditions in the study and they agreed with each other on those ratings. So density or thyroid tilt as an extension, perceptually can be recognized. 

Alexa: If the singers in this study weren't CVT trained, but came from another style [00:21:00] or from another methodology, or was a punk rock singer, what might you expect to see, or how might the tilt be described in, in this setup?

Mathias: It is a really interesting question, and it's one we also asked ourselves after the study, because we were, is this something that we've caused by teaching it in a particular way or is this something that's innate to human beings as a function that we have? And so luckily we have a, a collaboration with, uh, Dr Mark Tempesta from UNT, so North Texas University in the US. And he was doing his dissertation at the time at New England Conservatory interested in how to apply CVT to the classical teaching frameworks in general. And he recruited singers from the Royal Opera of London, singers who perform at the Met, singers who've been really internationally acclaimed opera houses.

And these singers had really no exposure to CVT whatsoever. They'd never met anything about this, like, what is this thing you're talking about? Um, so they were just kind of naive in that sense. They had plenty of training [00:22:00] singing in those places, but not CVT. And so when we had them scoped with the same measurement equipment that we had for our own study in the same clinical setup with the same doctor doing it, actually, lo and behold, the same tilt observations that we saw in our populations came through across the singer's vocal ranges, even up to the high C's in one of the tenors who did not really use tilt at all, who's singing very dramatic roles.

Another one, much more tilted because he's singing much, uh, software repertoire. So thyroid tilt or at least density and an extension and assume, assume a thyroid tilt, does appear to be a basic human voice function that can be taught and trained with techniques that target it if we know how to work with it.

Alexa: And what about if we are perceiving something to be tilt? How do we know that it is physiologically tilt? Are there any discrepancies between what we hear and what's actually happening and how [00:23:00] we then communicate that in the studio?

Mathias: That's a great question. We really should not rely on knowing that something has moved physiologically because we can't test it, which is why we always urge to use perceptual terms for our teaching studio that are grounded, of course in research that is physiological. But we can't test if something has moved.

I, I can't go and see ventricular folds have moved about three millimeter and, uh, vocal folds are now a little longer. We can't see it. We can assume it based on what we're hearing, but we can't see it. So it's much nicer to have a term that's perceptual. It sounds less weighty, less density, it's more metallic.

And we know from studies that then that most likely has these components to achieve that. But really we're looking at the perceptual side of things, first and foremost in the teaching studio. That's one point.

Second is that not all singers feel these things. Some feel them quite nicely, um, and they're quite aware of how it feels like, they have the proprioception or the inner sensation of what it feels like [00:24:00] to them, so they feel like more forward or more stretched, or it's thinner or like holding back or like singing through a muffler.

But others produce these sounds thinking more of the, let's say the produced sound. It has less weight, it's more restrained. Others use visual cues like taking a circle, filling it in. It's less filled in or using it more transparent color. Others use inner images like singing through a veil or through a curtain closing more.

And others think more functional about what's happening in the physiology of things. So we have to think that not all singers would cater to a learning style, a learning type, that is I can feel it. So we don't have to have the proprioception for that.

That is a really interesting question though. Can we feel it? And if we can, what actually is the reality of that? That's a great question to, at some point, uh, ask in a scientific study, like what are the singer's proprioceptive sensations of tilt and other singing techniques that are really specifically grounded in physiology? Um, I don't think of any of those in the field at the moment at all [00:25:00] actually.

Alexa: How do you feel it? 

Mathias: For me, I'm quite kinesthetic, so I, I have a sensation of it. I would feel it as a sensation of holding back, but also holding back by going a bit forward. So we often use the prompt for teaching of going a little as if you're saying something nice to someone, but holding yourself midway through the initiation of utterance.

Like, oh, or like kind of, hey, it has a kind of holding back to the note, but it's actually still going. That's my sensation of it. It's like as if I'm restraining the tone before it comes. Others are much more focused on other, uh, cues for it, depending a learning style.

Alexa: Some people talk about this idea of crying, like a little cry sound or whimpering, those sorts of instructions.

Is there a difference between what we are hearing perceptually potentially, or what might be going on physiologically between terms like cry, whimper, maybe whine, [00:26:00] twang, that sort of thing? Yes...

Mathias: yes. That will be another really interesting study to have endoscopies or other methodologies used looking at prompts for teaching. It's not very often done, I don't think in allow many studies at all documenting it.

We've done a few, uh, on our own, um, tools and prompts for teaching particularly density, and we've asked singers to do a little trick, uh, with cameras in and we see that yes, it does tend to produce vocal fold closure, but they also get a little longer and a little bit more forward, slightly more thyroid tilted if we assume that that's what's happening.

That's just the CVT framework basis. I don't know of many studies that actually look at the prompts to see if they correspond to reality. So I can't speak for the cry or the whimper. We don't have study data on that at all. But I think it's worth asking: if we use the same prompt with more singers, do we get the same result?

And in our studies we use and we recruit singers that are trained, having had [00:27:00] exposure to CVT because we know that when we then look at them, we tend to get really similar results so that they have, when we ask them to do a particular sound, what we end up seeing typically is both within themselves, they repeat the same thing over and over and over for the same prompts. We know that they at least have learned to do it in a particular way, and we ask someone else to do the same thing, we see the same result. So it is a perceptual prompt. We hear it as, let's say, an overdrive or less density or more metal. But what comes out physiologically looks the same across participants and across our studies. We have data going back to 2007, uh, and data as new as 2025. And they all look the same.

So that's, I think, really rewarding to know that the teaching prompts tend to lead to the same outcomes. Now I think that's in general something we should start exploring more in vocal pedagogy in our research. But that's a whole different question.

Alexa: Can I give you some examples of sounds that we might make in the studio, and can you tell me if you perceive them as [00:28:00] tilt?

So we might do something like, no. no, no. 

Mathias: Mm-hmm. I would say the first onset that has to kind of holding back sensation, I would think might be a tilt. Yes. 

Alexa: Some teachers, if they're helping a student to move through the transitional passaggio area, might use the same sort of cry instruction to help reduce a sense of thickness, reduce a sense of weight, so that it can travel up quite flexibly.

And they might use a scalic sound or a melodic sound, like a: go, go, go, go, go, go, go, go, go, go away. That sort of sound, is that something that you would perceive as tilt? 

Mathias: See, I think this one does several things. So that one for me does a change in the lower portion from something metallic and not so tilted towards something non-metallic in the middle. And also potentially adding more tilt. You're doing two things at once.

[00:29:00] And then it's also changing somewhat towards a more, let's say M2 type based vibratory pattern or falsetto voice- terminology doesn't really matter. Um, but the, the tilt might still be present.

So there are several changes along that scale that may or may not be tilt related and may or may not be metal related or may or may not be vocal full vibratory pattern related, or it may be all of them at once.

And so having terminology for all of them is really important. Uh, I think, I, I thought about an example earlier, like about this idea of mixed voice, for instance, and a lot of of things singers think of the elusive, I have to find my mix right. And when one singer goes, yeah, I want my mix voice is this. And for them it is decreasing the metal towards neutral, more non-metallic the one part what you just did. So it gets softer, it gets less cont, less firm reduction of the vocal folds. We get little less narrowing, a little less twang. Uh, typically a little lower, uh, a little lower, um, laryngeal position that's where they have a mixed voice. Great.

Someone else [00:30:00] goes, Hey, but for me it's this. They add more tilt. So they keep the metal, but they add more tilt, they get reduced density instead. Less compactness, both singers go but hey, I found my mix. It's great. Feels super easy. But they're really different productions. They're very different teaching as well for us to work with it. And if we don't know the difference as teachers, we may inadvertently give the wrong instruction and we may inadvertently jeopardize our singers' health by giving them the wrong direction of tool.

So I think we need to be really careful that we know what aspect is changing and why, uh, and what we're trying to achieve with it. When we say a mix, I think that's somewhat misleading. I think we can do a lot of different things. That's why I like, I personally like the continuous graduate scales of, let's say, metal or density or something else, if you like, better because it gives you nuance.

It's not an either or. It's not the is chest or it's mix or it's head or it's mix. It's okay, what am I changing? What aspect here am I changing? I think what you did before the scale is gradually changing several things. It's great [00:31:00] scale from cool singing, right? Um, but it also confounds a lot of variables.

Alexa: How are we as teachers able to pick up such nuances of lots of things happening at the same time in order to lead us to the best instruction for that singer?

Mathias: First step, realizing we need terminology that's precise enough to name, label, and categorize these things in ways that are consistent across singers. Finding the right frame -for me, it's this one, but there are others I'm sure.

Second, knowing anatomy, knowing our physiology so we know what certain directions might invoke of sounds.

And then we need to train our ears. We need to grow our ears as big as elephants to get the details, uh, and to learn to recognize, okay, when we have firmer adduction, it does this to the, uh, radiated sound. We have less density, so more thinning of the vocal folds, we get that direction of sound, less pressure results in that.

So mapping out these, these things. I would say they're easier to [00:32:00] map in perceptual pedagogical terms than they are in physiology 'cause we don't really perceive, or we don't change as singers only one thing, that we just saw, right? I don't just go, I would like 1.3 millimeters more longer vocal folds. We can't control that at will.

So we have to think of the whole system as coordinating. Um, so we have to give, let's say, control buttons to these small aspects. And so that, I like the, the metal as one 'cause that's the narrowing, it's the pressure building, it's the tuning of my system for certain resonances. Density is the sensation of the tilt of the holding back or the restraint, without that entails some stuff. Then the modes with the vowel choices, the mouth configurations. Uh, so I can really set those up knowing how they interact with pitch as I go through my range. So I have control buttons for all the aspects that at least in my perception has clear meanings and have clear directions of change that I know how they relate to pitch, to volume, to quality.

And then [00:33:00] from there we start exploring with our singers. Okay, you like that expression? Cool. That requires now raised soft palette or compressed tongue or lower larynx to get the coloring you would like, but let's remain in the same function so the function stays. I'm coloring around it so that I get the sound I would like without losing or confounding variables.

Alexa: Could you give us an example of when using a a tilted target might compromise a singer's efficiency or health? 

Mathias: I should caveat by saying we can't necessarily know when singing is unhealthy without asking for the prompt for the feedback from the singer themselves or actually seeing it.

But we can kind of assume based on, let's say, learning that certain things tend to lead to certain problems. And I think one big one we see is when singers try to do more tilt which tends to be also more open epilaryngeally, so we get less narrowing, less what we call twang in CVT, more of epilaryngeal narrowing in Titze's terminology. So the space just above the vocal folds tends to get more open. That tends to be less efficient, which is [00:34:00] fine if you're not singing too loudly. But if we do that less efficient setting with now stretched vocal folds, and we drive that with a lot of subglottic pressure, that is, I would say a straight chance of going into phono trauma.

Alexa: And what would that sound like, potentially? I'm not asking you to damage your vocal folds, by the way. 

Mathias: No, I won't do that one. But, um, it might sound like forcing or pushing, it might sound like that the voice is wanting to split into two sounds, wants to go at one point, both heavy and loud, another point both light and kind of breaking away for you.

It might also sound like creaking or like vocal fry appearing in a much higher pace where it typically, uh, appears for a lot of singers. I think an example that, uh, the singer themselves have talked about, so I shouldn't, it shouldn't be shaming anyone, Demi Lovato was singing Skyscraper live at some point, uh, and some of the high notes at the end, uh, in a not so well monitored situation, so not the best setup for doing vocal [00:35:00] acrobatics and she ended up pushing that volume quite loudly. And to my ears, that sound that we talked about colleagues around it, that particular sound sounds like it has more of, let's say less density, meaning more tilt and lo and behold, it was not sustainable. It, it had the creaking kind of spitting sound. It sounded cool, but it led to some issues and troubles down the road. Um, and now when that person sings that live, they don't ...do something different, uh, and it's much more sustainable.

That's one short way of getting into trouble is when we want to have the TA going, yes, a lot of me. CT , yes a lot of me. And then we also drive up a lot of subglottic pressure that that is not a great corner to go to. 

Alexa: So as an example, if we took that scale from before, we were doing the Gogos as a way to sort of transition, get into some form of belt approach, however you might be using it, and someone was going.

Go, go, go, go, go, go. That sort of sound?

Mathias: Yeah, that, that's [00:36:00] excellent example. I would say, um, I would, for this particular sound, I would have to ask what are we trying to achieve? Are we trying to get metal up higher into our range, which we know we can do we've done that testing in a different study. We can sing up to at least C5 and also above F5, G5s with metal, no problem, with certain limitations on coloring choices when we go that high. 

Alexa: And is that the perception of metal or is that the physiological... 

Mathias: physiology of metal. Looking at EGG. Yeah, we look at that in a four active range in a recent study. So we can see, we really can get there with the same vocal fold vibratory pattern, but that means it gets louder, it gets brighter, it gets even more metallic in perception, right?

Or we're trying to go up to the high note in a way that's a little less density, a little less metal. So closer to a, let's say more neutral kind of, or more head voicey if you want to use that terminology kind of space, because then those two directions are very different, right? One might lead you to train how to work with the weight in a healthy way, how to not drive it too hard, how to maintain a [00:37:00] narrowing, how to maintain the, the formant resonant kind of tunings that you need to go.

The other path would be okay if you want to look for a thinner sound, the less density sound then we train for the more tilted sound, the more, let's say health sound. We choose vowels that help us go there. We choose volumes that help us go there. We choose effort levels in terms of support values, or let's say mechanisms of breathing and support that allows us to get there.

So we have to then get the whole system rebalanced for the goal we're trying to achieve.

Alexa: If I understand correctly about Kerrie Obert's work, I think I remember her saying this sort of idea being similar to twang and low larynx. Like, if you're trying to get twang with low larynx, it's not gonna work. They don't like each other. So just understanding what friendships there are with the instrument and the targeted sounds will help us to make some good choices about instruction and the way we set a sound up.

Mathias: Definitely.

I'm also big on vowel shapes and CVT as a [00:38:00] framework is big on vowel shapes because certain vowel shape will help us achieve much more easy some formant tuning patterns. Um, so to get higher with more vocal fold, firm adduction and now without hurting ourselves, we start relying much more on having to align really nicely, uh, the formants and the resonances.

Whereas if we do reduced density stuff, we get a bit more leeway 'cause it's not so loud, so we don't have to get as efficient. Uh, so we can play more around the vowel shapes. Typically, the UH vowel shape is really nice to explore. A lot of singers like that one, I like to call it the UH sandwich, have an UH bun, whatever vowel shape you like, another UH bun smooshed together, and you get kind of all vowels in between that sound like the vowel you wanna sing, but they're not really, um, which is great.

Um, but that again, it's a path driving into a more tilted, less weighty kind of sound, which is really cool for certain genres and styles. But there are, let's say we're a dramatic tenor trying to sing a lead dramatic tenor role going to our high C, [00:39:00] it wouldn't be variable to lose the weight as we go up. We need that weight to get the drama. 'cause if I sing it with too much tilt, or I'm not a tenor, but if I were to sing as a high tenor C um, I did that with too much tilt or too reduced density it doesn't have the drama. It might be easy to make, it might be efficient to make singing is healthy enough, but it doesn't really fulfill the requirements of the style nor the performance context that I'm in.

Um, same thing if you are a female theater singer, singing let's say some of these new ones coming out like, uh, My Days From The Notebook or She Used to Be Mine from Waitress or Evita. Those roles they call for metal above D five, but metal not in the fullest, loudest version like Jennifer Holiday for instance, did.

So we have to find a way to get to those notes where we have a little less metal but still have metal. That would be by using a little less density as we go up. Are we singing Dreamgirls and Jennifer Holiday's I Am Changing, most likely [00:40:00] I would favor not losing the metal and keeping it up to the F5, but learning how to do it in a really efficient way.

Now, are we singing something classical like '. ' for instance, that repertoire doesn't call for the full drama, right? We have to get some of the weight away. So I think depending on what we're trying to achieve as an artist or as a singing teacher, helping an artist achieve what they want to achieve, it's really knowing the toolbox and knowing what sounds are possible, in which ways, and how do I get them there?

There isn't really one style or one exercise fits all. There is a lot of path to different sounds, depending on requirements.

What we know from the study is that thyroid tilt is invariable to registration. We can do this on top of all kinds of sounds that belong to an M1 type of box, if you wanna talk that terminology, we can add it also to the M2, let's say type of vibratory patterns.

So the tilt is an independent variable we can play around with on all of these. Do you wanna try one of those? 

Alexa: Sure. 

Mathias: Yeah. So could you give me kind of easy, [00:41:00] high pitched AH vowel in falsetto. 

Alexa: I hate an AH vowel Mathias, so Oh, 

Mathias: okay. Different vowel shape, that's fine. 

Alexa: Let's go with an E. This is an easier one. 

Mathias: Sure. Great. M2 vibratory pattern. Mm-hmm.

Alexa: EE...

Mathias: comfortable?

Alexa: Yeah. 

Mathias: Great. Before that sound comes, do a little... as if you're stopping yourself from telling someone some good news.

Alexa: We

Mathias: nice. Comfortable still?

Alexa: Mm-hmm. 

Mathias: Great. That's still to my ears at least M2 based. It's still falsetto based. Yeah. 

Alexa: Yeah. It feels, yeah. 

Mathias: It has a different kind of feel to it in sound than the other one. Right? So your ears, what's changing between those two? 

Alexa: My eyebrows. That's what's changing.

Thankfully I have a fringe so you don't have to see it. But, but the eyebrows are totally in action and yes, one, one feels floatier, compared to another one which feels thicker without having to change a feeling of register. And the second one is something that I might use in like legit [00:42:00] training. And the first one kind of can float around in many a different genre. 

Mathias: Yeah, I agree completely. 

I think it's a really nice example of how the, the tilt sensation, or in this case, a teaching prompt for density to make it easier really can help us find nuance within a box of one register. And that's one of the reasons why I'm, I'm not a big fan of registration terminology. I, I do like the idea of vibratory pattern distinctions, but even within M1, that box as a whole, there's a lot of nuance that can be done with a voice.

Uh, and there's a lot of different vibratory patterns for vocal fold oscillations. The same thing goes within the box of M2. So I think knowing a different terminology that can unbox those boxes in a systematic way is really helpful. And those two sounds, we hear both of those music, what you just did, both the first and the second will appear in all kinds of sounds like the first one, easily in a pop music even also in a few musical theater piece.

The second one, maybe more musical theater, kind of easy ways to get to the high notes that [00:43:00] sound like more beefy than singing them in a full, powerful way, but still not quite all the way, or singing the chorus easily making louder sounds without having to be so effortful about it. 

Alexa: As you mentioned before, something that you explore in your studies is this question of if tilt lengthens the vocal folds, why doesn't pitch rise? And there are some other technical positionings that we might explore with a singer like, moving the tongue more forwards, which is said to put a stretch on the vocal folds.

So what are your thoughts on and, and findings on tilt and but not actually pitch rising at the same time? 

Mathias: It's a really good question, and we had that question pop up a few times after the pilot.

We didn't really know what to expect from that pilot. So when we saw the thinking thought, Hmm, it's lengthening, shouldn't that go up in pitch? And it didn't and we went, okay, it didn't go up. Why didn't it go up?

So the, the bigger project to look at that as well, and if you look at the discussion of that paper, it really is a lot about [00:44:00] pitch and compensating factors for not getting a higher pitch and the result in what we hear as less density or less weightiness.

And just to get the, everyone on the same page, fundamental frequency, which is what we measure when we talk about pitch, pitches really are perceived contour of that, depends on balances between quite a few factors. That includes vocal fold length first of all, that's the easiest one. Vocal fold tension also -the vibrating mass. Vocal fold tissue stiffness, and aerodynamic forces such as subglottic pressure, transglottic pressure, and other air flows measures. So we get this kind of mm, really complex mixture of things that have to line up in a particular way to get to a certain fundamental frequency for a certain particular perceived pitch.

So if we think about a thyroid tilt, assuming that's what's happening with this particular sound, that would impact some of these factors such as vocal fold length, vocal fold tissue stiffness, vocal fold [00:45:00] tissue tension. And we know from previous studies, and these have been repeated across different scientific methodologies, that contraction of the CT muscle, when it acts upon the thyroid cartilage to really elongate the membranous vocal fold portion that accounts for almost all length and pitch changes in the low and middle parts of the voice, the so-called model voice and speech. And 70 to 80% of vocal fold lengthening in the higher parts of the voice are also based on the CT contraction.

So it's kind of baffling and we can now do the same thing but not get a higher pitch. And so we went, okay, we can't really comment on the measurements that we have vocal fold tension or stiffness, cause that's not really observable by endoscopy. We also can't really comment on the amount of mass vibrating, 'cause it's not the type of methodology that we have. But what we can do is try to synthesize what's in the field from other studies and hypothesize what might avenues be to explain what we're observing for future, for new studies to actually look at.

And what we found was three [00:46:00] avenues that might explain compensatory factors. Um, and they are really mechanical and aerodynamic in a way.

So we found one that could be, for instance, that we are decreasing subglottal pressure that would lead to not getting a higher pitch if we kind of do it in the right amount.

It could be changes in the amount of vibrating mass and how much the TA muscle takes part in vocal fold vibrations.

Or it could be changes in laryngeal subglottic and air pressure adjustments that costs decreased air flow as an overall net.

Now, which of these potentially and even fourth or fifth compensating factor has not yet been studied in detail. We've done a preliminary study with Marie '. ' in Finland and her supervisor , and they are really looking at aerodynamic measurements of these density variations has just been accepted for publication ...

we also have studies coming out using MRI with excellent researchers, [00:47:00] uh, doctors in Germany, um, and their colleagues using really cutting edge around MRI techniques looking at both classical and CCM singers.

Also working with phenomenal modelist, uh, Dr. Chang in LA and he's looking at trying to address these modeling issues. Can we really try to tease out what aspects are changing? Is it the pressure? Is it the flow? Is it mass? Is it tension? And, and so hopefully within the few years of working with these really excellent groups who have better answers to that question, for now, we have hypotheses that we can't really say one or the other yet.

I will say based on, based on the data that we are coming out with very soon in Folia, it looks like at least a piece of that puzzle is decreased subglottic pressure. But that might also simply be that we lowering the volume accordingly. So we don't know yet if that's the only thing.

Alexa: Maybe it's the CT going, bitch, you underestimated me. I'm just doing, I'm not just a, a pitch changer. 

Mathias: Yeah, [00:48:00] but hey, isn't that cool though? We have the same muscle doing two different things. I have more purposes. 

Alexa: Yeah, I'm gonna go with that one. 

Mathias: Pedagogical...

Alexa: yeah. Steeped in science.

What is the enemy or a hindrance to tilt if we're wanting to bring about a sense of less metal or less density, but we are not quite getting it? 

Mathias: That's a good question.

I think we see a less variability in the tilting because of the antagonistic relationship between the TA and the CT. So we can do some, but we can't do as much.

Other enemies or let's say other counter potions to getting tilting, uh, might be aspirate onset. People tend to use H onsets and then they, that aspiration tends to let out holding onto the tension. Some find it by using more of a bite setting, so they're kind of biting into an apple, showing your upper teeth, the what's called megaphone shaped vocal tract by Ingo Titze and, and [00:49:00] colleagues.

Some actually find that when they do twang and here, I mean epiglottic funnel twanging, not, not other kinds of quality twanging so epiglottic funnel narrowing, um, sometimes help them not get the vocal folds to be so stretched. Um, and there are many other tools and problems for the same thing. In general, I would also say that the lower we go in fundamental frequencies or the lower we go in pitch the less likely we are to produce a sound with thyroid tilt, because low notes can't be done with really long vocal folds.

Alexa: What would you say is the lowest note that tilt can really be applied to efficiently?

Mathias: That's a great question. We don't have enough data, I would say, to say this is where it has to happen. From teaching experience personally, and from the institute with my colleagues, I would say we tend to invite the tilt in for a female voice for classical singing, at least E4, F4, G4 kind of around there, depending on voice type.

But now if we're singing other styles, than classical western operatic classical like singers, or heavy [00:50:00] metal or we're singing rock in general, or even louder pop singing inviting the tilt in volitionally we don't have to until F5 or G5 or not at all. So, so it depends again, here, meaning enough tilt for the note because we need some of course CT action to get the vocal fold stretch for the note. We can't avoid that. The higher we go, the less, let's say navigating room, we have to tilt even further, of course. Um, but it really depends.

So the lowest that we can get to, if I were to go with that voice below an E4/D4 with a tilt, it starts getting really hard. Below C4, and it gets even more difficult for the female voice.

Alexa: And for the male voice?

Mathias: We haven't got data for that particularly yet, I can't comment properly on that. I think in the study we did with the four octave range, uh, in Prague with my and colleagues, we saw it disappeared going below G3 into the really base part of the range, then it becomes unsustainable [00:51:00] even if we can still produce falsetto down there. So the, the M2 or head voice kind of registrational stuff exists really, really low, but it's not tilted the thyroid tilt.

Alexa: So to go the other way then, if you were working with a singer, or if we were working with a singer who was just using a lot of tilt and, and relying a lot on that percept, what would be a tool that we could use to help them come away from that in order to fulfill the drama of a song where it's required?

Mathias: I might choose a vowel that's more like an EH, as in END or an EY as STAY, higher back tongue touching in the molars, tip of the teeth go, sorry tip of the tongue touching in the lower teeth. I might want to open more at the front so we get more opening here, more narrowing here, meaning more twang, somewhat higher laryngeal position.

We're fa favoring vowel shapes that can be more twanged in general, so we get brighter and brassier, but that help, um, not too high contact quotient, but high enough to get what we need. Sometimes doing it, exercising with, let's say a bit [00:52:00] more of the weight helps us let go of the sensation of not having to have the weight, which is kind of nice in a way, they fit together.

Sometimes even just telling a singer to turn the volume up by two out of 10, they go, okay, that's gonna require much more, but don't turn up the air pressure. Don't give it more support. Okay, what then what I do? Something has to change here. Uh, and then they reorganize. It depends again on what they're coming from, what they're doing and how they favor it.

A lot of singers that work with the tilt have learned more rounded vowel shapes, the OHs and the OOs and the UHs because they tend to be much easier to do with more tilt. Um, so we have to go another path to get out of those patterns and those habits.

Alexa: If you had to sum up the biggest misconception about tilt what would you come to? 

Mathias: Oh, one common misconception that I, at least in my guest lecturing around the world of universities and conservatories tend to be faced with is this idea in classical teaching particularly that we must learn to tilt. [00:53:00] The voice has to tilt.

I don't necessarily believe, personally, I have to say here, that we have to learn to tilt with volition or control necessarily. I think it's dimension of voice control that can give us a lot of control and gives us nuance and some specific variations of our voices, but some styles don't need it. And some repertoire doesn't need it. , And depends, so depending on who we are in voice type and fach and style and these things, we may not actually need those variations. Um, so there isn't, in my personal personal opinion, at least, there isn't a one size fits all for singing teaching. And a lot of singing teachers seem to promote this idea that all high notes need more thyroid tilt to be healthy. It's not really what our data shows.

Some singers in our studies are living a happy life, singing sustained C5s, D5s, F5s, tenors singing the high Cs without learning to adjust more tilt than what the note [00:54:00] requires to get to it. That that's one of the misconception.

Another one is that we can keep the tilted position throughout our range, including the lower part of the range.

Physiologically, this makes very little sense I think personally. Um, if we go for a lower pitch or lower fundamental frequency, that requires the shorter vocal folds to allow for the slower oscillations that produce lower pitches. When we tilt, we elongate the vocal folds. At least that's the theory, which then basically is an opposite direction of what a low, low sung note requires. 'Cause the tilt will require or at least invite in faster vibration. So pedagogically speaking, it makes it extremely difficult, also, sometimes counterproductive to seek to use the sensation of the tilt throughout the entire range, particularly if you want to achieve power or volume in the lowest part of our range.

So I think particularly for the females Sopranos and Altos singing Western operatic voice traditions, trying to achieve the middle and lower [00:55:00] portions, particularly the lower parts of their range they have to learn to let go of the tilt and find the metal instead.

Alexa: Other than some of the things that we have touched upon what other things do we still not know about tilt, and what is your burning question that you want answered about it? 

Mathias: So, as I said earlier, we are still in ongoing research around thyroid tilt and density, perceived density, particularly use using methodologies that are more quantitative in their nature, like looking at vocal fold angles, vocal fold length changes, cartilage movements relative to fixed structures, looking at aerodynamic perspectives of pressure flow ratios.

So we need some of these methodologies that are a little less accessible to singing types of studies usually like having MRI or CT scans. We also need more, I think around how tilting or density changes impacts vocal fold elongation and how that impacts vocal fold vibratory kinematics. We've got some [00:56:00] initial observations around reduced contact quotient from ETG measurements, and we know a little bit about MFDR measurements and these things from, from flow, uh, inverse filtering and things, but we need much more information as to what portions of the vertical aspect of vocal fold tissues are impacted and how they're impacted.

We need to know a lot more about what happens across the singing range with this, where does what happen and how can we observe these things? But the problem here is that our measurement, uh, tools are not built for singing. They're built for pathology. So taking a singer into an MRI, okay, that's cool. It's a cool system. It's really expensive, but it's cool.

But now you have to lay still, lay into the tube, but not a lot of good feedback, sing a note, and if it's a good scanner, we can do it in real time, getting a little 2D video, but that's not realisable in terms of good outcome. Or they do it like 15 second kind of holding the note. Nothing has to change. Just be really stable. And then you get a nice 3D scan of the vocal tract- really cool. You can't see [00:57:00] vocal fold tissues vibrating. It's static. Now, lisa Hasa and her colleagues and five are doing really cool work around making dynamic MRI. So video MRI of the vocal folds in a high speed version.

To do that you as a singer, you go into the tube. We did this, uh, last year, going to the tube. You lay down, you sing the note for five minutes. Which is cool. Of course, if you're really good at singing the same thing for five minutes without getting any fatigue, that's for one sound. Then you want study, let's say 10 sounds, 15 sounds, 50 sounds, you just times that by five and you end up dying in the tube.

So it's, it's a really hard, so our tools are not really built for what we want to answer in questions. So we need to instead start relying on modeling types of studies where we take measurements in vivo from singers and from speakers like aerodynamics, stroboscopy, endoscopy, MRI, static images.

And then we have someone like Dr Chang, for instance, who is an excellent modelist, but that [00:58:00] requires computational power, requires focus and requires data. So it's, I think we have a lot more fun ahead of us with density and tilting, and also comparing it to other approaches to it. Is it Estill uh, that works with cricoid tilt?

Uh, not that I know how I, I'm not an expert on this, so, so, uh, pardon my um, non knowledge here, but I am, it's my understanding that the idea of the cricoid tilt is that it increases vocal fold thickness so you get more mass. Uh, so that will be counteracting what's happening with the thyroid tilt.

I remain somewhat skeptical towards the notion of the cricoid tilt because I'm not sure how that's really comfortable for the trachea and all that stuff, but let's see what comes. It might be a passive reaction to other muscles moving. Um, I'm open for that. If that's the case, we need to look at how do these things go together in a systematic way? What happens in singers that systematically can control as much as possible in their [00:59:00] system?

Uh, that's another point. It's really hard as a singer to only vary one thing 'cause we are in an interconnected system. Uh, so when you're making these kinds of studies, we have to make protocols that are so big that we try to account for all the variation that might occur in a systematic way so we can really compare apples to apples, not just across different data sets.

Um, so I think we have many open questions ahead of us in that respect.

Alexa: Where can we keep looking out for your work and get in touch with you with any questions we might have? 

Mathias: So, um, I think a good resource to start with everyone to learn about these tools and how to hear them, how to work with them we have a free app available for smartphones, for IOS and Android. Go check that out. It's really cool. It's free downloadable. 

We also have a website where all the papers are listed, so if you wanna see the research papers and what we're getting up to in our little labs around the world check out the site. I think's gonna be in the description of this...

it's gonna be in the show notes. Yeah. And just tell us what your app's called. 

Uh, the app's called Complete Vocal Technique Intro. So it's [01:00:00] free and full of fun audio samples, links to YouTube, tons of images, descriptions of techniques so you can get started on learning what are these things, how do they work, which is always kind of cool.

Um, and then otherwise reach out to me by email. I'm always open to chats.

Alexa: And when do you expect this next part of your journey and research to be complete? Basically, when can we book you to come back and tell us what you found out? 

Mathias: Um, we've got three studies that just came out actually this, uh, January. So we have a lot of fun stuff coming out.

We've got a whole series of tests with, uh, typical S-O-V-T-E tools and how they impact these sounds coming out soon. Got a whole series of papers coming out around vocal effects and how they're affected by some of these, um, tools and techniques. So anytime I'm happy to come back.

And I think I should maybe say that I think we're in a really interesting period and traditional period in contemporary singing technique and classical singing technique where they're kind of starting [01:01:00] to converge in a more functional understanding and language. I think it's really exciting to be a researcher and a teacher in this time because it, we are looking at more varied singing populations. We are looking at singers from diverse backgrounds of styles and genres. And we are, as teachers, increasingly faced with or realizing hopefully, that we need to meet and serve a variety of singers and expressions that is beyond mono genre, mono style.

And so this opens up a lot of avenues of research and teaching that's much more tied to the basic function of what we're doing. Um, and looking at techniques that are useful across singing than just one genre. And that requires, I think, as teachers that we are flexible and we reflexive and ready for change as a knowledge basis change.

Because at the moment we, we know something about tilt, we know something about how that impacts vocal fold behavior and perceptually density. That'll be much more learned, i'm sure. So what was used [01:02:00] one year ago, or let's say a hundred years ago, it's really an interesting knowledge base and we can be inspired by it, but it, I don't think necessarily it's the foundation of which we build contemporary practice and scientific inquiry.

But we could see with the first Garcia's first, you know, scope of the little flame in the mouth, that's a hundred plus years ago, right? Those are interesting studies that we need to be aware of. But most likely what we build the future on is much more contemporary.

That means specifically, right, that we are now looking at new tools like AI that's gonna allow us to analyze much larger, much more complex data sets.

We're looking at, I just mentioned this study, with colleagues, right? Much more advanced imaging technologies that allow us to look at never before available details about vocal function such as high speed MRI. That's cool. The use of novel modeling approaches like what Dr Chang is doing with increased compute power, right?

So we can do things that we couldn't even think about and even have questions for 1, [01:03:00] 5, 10 years ago. And much more people that are not scientists necessarily are equipped with high quality microphones, high quality audio change that we can then in our own singing teaching practice, record really good audio quality that we can then analyze with Praat or other types of softwares that are open source because quite complex acoustical measurements from our bedrooms. And I think this is really exciting 'cause it bodes for a decade or maybe in a century of rapid advancement in our understanding of and teaching of voice that requires us to be, I think at least I'm expecting that I'll be teach, changing my teaching practice in the next five or 10 years a lot cause we have to follow what we learn about the voice functions. 

Alexa: Oh, I've had so much fun chatting with you, Mathias. Thank you so much. It's been so interesting.

Mathias: It's been a pleasure. Thank you for the invitation for the fun time together.