So let’s talk about vibrations. There are lots of things around us that cause vibrations
in the air all the time. And we’re really sensitive to these tiny, miniscule differences
in air pressure, because those little ups and downs are what we mentally experience
as sound. When we talk, we’re making it happen, the air from our lungs pressuring
the world around us. But we don’t always vibrate the same way. I’m Moti Lieberman,
and this is the Ling Space.
So in earlier episodes, when we talked about how to define speech sounds, we noted that
one of the things we pay attention to when we’re listening is if our vocal folds are
vibrating or not. If they’re vibrating, we get a voiced sound with some buzz to it,
like a [v]. But if they’re not vibrating, then we get a voiceless sound that’s notably
quieter, like a [f]. Everything else about these sounds is the same – it’s just a
question of whether they have that underlying vibration that makes us hear them differently.
Whenever we talk, we press air out from our lungs, through our larynx, and then through
all the minute manipulations of our vocal tract to shape the wave we’re producing.
And it’s true when we look across languages, voiced sounds vs. voiceless is the most common
way we deal with phonation, or the act of producing sounds. But as it turns out, there are
a couple more settings humans can use in creating the vibrations that hit our conversation partner's eardrums.
Instead of a binary choice, we should think of voicing as more of a range of how free
the path is to get that air out into the world.
So at one end of the range, your glottis is just 100% closed, and no air goes through.
That’s a glottal stop, but that’s about it. We can’t use it beyond that for speech,
because, well, the passage of air is important for speaking. It sort of is speaking. But
that’s one extreme. At the other extreme, there’s zero closure at all. Your vocal
folds are just set 100% open, and the air calmly and blissfully flows through to your
waiting mouth and nose. That open state is what we experience as a voiceless sound: free
flow through the larynx means no vibrations, and no vibrations means no voicing.
So what is voicing? Well, it’s what we get when we set our vocal folds closed…
but then we start blowing up air from our lungs behind them anyway. Before long, the pressure
below our larynx gets too great, and the vocal folds are pushed apart. But the air suddenly
rushing through the gap creates suction, due to the Bernoulli effect, and the vocal folds
quickly get pulled shut again… only to get blasted apart once more. This voicing cycle
of blowing apart and whooshing back together is what creates the buzz we can hear and feel
in voiced sounds like [z] or [m].
Okay, so far, we’ve covered three vocal fold positions: no air flow, open with free air flow, and
regular voicing, where the air gets released cyclically. So we can basically list these
in terms of openness of air flow, like this. When we do that, we can see there are two
other possibilities in between the positions we’ve talked about. One is that we could
produce sounds where air can get out, but not as easily as with normal voicing. And
the other is that we can make sounds that let more air out than regular voicing, but
still not as freely as if it were voiceless. And it turns out, human language uses both
of these possibilities! We’ll do just about anything with our vocal folds that we can
figure out how to do.
Let’s take a look at the more open of these first. What can we do with our larynx to make
everything looser? Well, we can just not quite close the vocal folds completely when we’re
doing our voicing thing. Since the whole time you’re talking, you’re blowing up air
from your lungs, as long as there’s some opening, that air will keep escaping. So if
you don’t quite close the vocal folds, then on top of the regular wave that’s getting
produced from the vibration, there’s just some extra air that'll make it out, too. This
airflow gives these sounds a characteristic breathy quality, so speech produced this way
is said to have breathy voice.
Because breathy voice happens on top of the way that we make voiced sounds, we can potentially
produce any kind of voiced sound in any language with it. If you want to write out breathy
voice, you can use two little dots under the sound, like for [a̤] or [i̤]. But it’s
not just for vowels, it’s also nasal sounds, like [m̤], or approximants, like [ɹ̤].
Even voiced stops can have a breathy voice associated with them, like [b̤] or [d̤].
Breathy voice isn’t super common in English, although there is one place where we can sometimes
find it, and it’s with putting an /h/ between vowels. Try it yourself: try putting
your hands over your ears, and then saying a word like “ahead”. You’ll feel the
vibration carry through the whole time that you’re saying the [h], but that doesn’t
really make sense, since [h] can’t be voiced itself. [h] is a glottal fricative,
so voicing it would be asking your vocal folds to do two things at the same time. Instead, you’re
getting breathy voice. You get [ɦ].
But even if breathy voice isn’t common in English, you can still find a solid bunch
of languages, particularly South Asian ones, that use it to differentiate between words.
Like, for example, Hindi has [bal], with a regular [b], which means “hair.” But it
also has [b̤al], with a breathy /b̤/, which means "forehead".
Or look at Newari, a language spoken in Nepal and India: there, [naa] means “it melts”,
but [n̤aa] means “knead”. So that change in how we do our voicing really can cause
a meaningful difference.
So that’s what happens when we let through more air when we’re voicing. What if we
let through less? We can tighten up our vocal folds, making it harder for them to vibrate
normally. Like, we can keep the back part of the vocal folds closed completely, and
the front part will only vibrate slower, because it’ll take more effort for air to come out.
This makes your voice sound like it has a lower pitch, because slower vibrations mean
that it sounds lower. But doing this also makes your speech sound like this, and so
it’s also known as creaky voice.
Much like with breathy voice, creaky voice can be applied to any sound that’s usually
voiced. And we also mark it under the sound, here with a tilde, so like [r̰] or [ṵ] or [z̰].
Using creaky voice to distinguish between meanings is also not super common cross-linguistically,
but it does happen. For instance, we can find creaky voice in Danish, where the regular
versus creaky difference at the end of the word changes the meaning.
So a word like [bœn] means "beans", but [bœn̰] means "peasants". Or [du] means "you", but
[dṵ] means "tablecloth". And we can even find languages that have both breathy and
creaky voice, like in the Mazatec languages spoken in Mexico. There, [ndæ̰] means "buttocks",
but [ndæ̤] means "horse".
Of course, even if a language doesn’t use breathy and creaky voice to cause a change
in the meaning of its words, that doesn’t mean that we don’t use it at all. Both of
these phonation types show up in all languages, to mark social cues or just in different phonological
environments. It’s too handy of a tool for making us sound different to ignore. In English
in particular, you may have run into creaky voice lately: it’s very common in the speech
of young women, and it’s been demonized as sounding grating or annoying, or even being
damaging to the vocal folds.
But of course, that’s just not true. That’d suggest that for all these languages with
creaky voice, people are just going to wear out their vocal folds over the years. Copenhagen
isn’t full of people forced to whisper because they’ve creaked their voices away. And everyone
uses creaky voice some of the time. It’s particularly common in English at the end
of declarative sentences, where our pitch goes down. Now that you know what it is, if
you listen for it, you probably won’t have to wait long before you find it in your own
speech. The treatment of creaky voice in English is just another shot at how young women speak,
like how the use of “like” used to be attacked. There’s nothing inherently bad
about it. Personally, I think it sounds cool.
However you feel about breathy or creaky voice, they both represent different ways of producing
part of the expansive range of sounds that humans use for speech. Sometimes it’s to
differentiate between words, and sometimes, it's a social cue. We play our larynxes like virtuosos,
voicing and creaking and just letting the air flow out. But any way you do it, human speech
makes a lot of good vibrations.
So we’ve reached the end of the Ling Space for this week. If you let our speech waves
impinge on your eardrums, you learned that there’s more to voicing than just voiced
vs. voiceless; that we can allow more air out along with our vibrations and get breathy
voice; that we can tighten up our vocal folds and make ourselves sound all creaky; and that
even if it’s rare for languages to use these forms to change meanings, breathy and creaky
voice are really common within languages as social cues or allophones.
The Ling Space is produced by me, Moti Lieberman. It’s directed by Adèle-Elise Prévost,
and it’s written by both of us. Our editor is Georges Coulombe, our production assistant is Stephan
Hurtubise, our music is by Shane Turner, and our graphics team is atelierMUSE.
We’re down in the comments below, or you can bring the discussion back over to our
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And we’ll see you next Wednesday. Haa ci gin!