Line Hilton discusses how to smoothly navigate the transition and develop a healthy, balanced mixed voice.

For most singers, the ability to move seamlessly between chest voice and head voice is a top priority. And so, by extension, it’s vital that singing teachers understand how the transition works and how to solve any problems that occur in this area.

“Teachers will spend a lot of time working with students on the transition, so they need to know what’s going on,” explains BAST founder Line Hilton. “It’s about finding songs and strategies and using vowels, consonants and scales to help with that.”

Recently on the Singing Teachers Talk podcast, Line took listeners on a deep dive into the transition (also known as passaggio, bridge, register shift or break). Here’s a taster of what she had to say.

Where does the transition occur?

“In contemporary voice, the first shift between chest voice and head voice is around A♭4 for females, give or take a few semitones,” Line says. “For males, it’s somewhere around E♭4. 

“There is a physiological shift there, and any other shift after that seems to be more acoustical. For females, the next one is somewhere around E♭5. For males, it’s somewhere around A♭4.”

All sorts of factors, such as age, and the condition and physiology of the vocal folds, influence the transition.

What’s happening mechanically during the first transition?

“If you’re singing in chest voice and want to go higher, something has to change,” Line says. “TA (thyroarytenoid) is mostly in control of the lower end, and, as we go up, our CT (cricoarytenoid) needs to start to engage. And so we have a mix of those two. This is sometimes called mixed voice – as in a mix of TA and CT.”

In terms of voice training, what’s the end goal?

Line uses a rather good analogy about driving a car to answer that question.

“If you want to sing with chest voice and head voice and move between the two, your goal is to do it without anyone noticing,” she says. “But the fact is there is always a shift [even if it’s not discernible to the listener]. Mechanically, it’s like changing gears when you’re driving a car. We could bunny hop down the street as we change gears or do it smoothly.”

What does it take to sing through the transition smoothly?

As the vocal equivalent of a bunny hop doesn’t sound appealing, achieving a smooth transition requires finding a balance between the TA and CT and controlling the larynx.

“If it [the larynx] is too high or too low, that might impact vocal fold closure. If I’m going through the transition, and my vocal folds aren’t closing, or there’s lots of air, I might not feel a transition.”

What potential problems can occur when a singer moves through the transition?

There are three possibilities:

• The singer is TA dominant. “If a singer yells their way through, they’re TA dominant. As they go up and through the transition, it will sound like their pushing or pulling. What’s happening functionally is that the TA is trying to do the job of creating pitch as it goes higher when it needs to back off and allow the CT to come in.”
• The singer is CT dominant. The other option is the singer doesn’t engage any TA, and the sound is weak.
• Poor TA/CT coordination. If there’s a nice balanced sound at the bottom, but the singer is flip-flopping or wobbling when they go higher, poor CT/TA coordination is the culprit.

Developing balance between TA and CT

The first step is to figure out what’s going on functionally. “Quite often with TA dominance, the larynx is also coming up, so in that instance, we need to stabilise the larynx and get that into a more neutral position,” Line says.

“Initially, we might even go to the opposite extreme and get it in quite a low position just to disengage those muscles that want to bring that larynx up.”

Exercises to develop mixed voice

For a detailed explanation of the type of exercises to help navigate the transition and develop mixed voice, tune into the podcast here.