1 of 20

Chest Voice, Falsetto, and Mix: Oh My!

The Science of Vocal Registers

Dana Zenobi, DMA - Assistant Professor of Music (Voice)

School of Music

Jordan College of the Arts

2 of 20

Today’s Adventure�

Defining Vocal Register

Mechanical Aspects

  • Laryngeal Modes
  • Spectral Slope
  • Exercises

Acoustic Aspects

  • Auditory Roughness
  • Absolute Spectral Tone Color
  • Formants & Vowels

More Nuanced Models

Take Aways

3 of 20

Framing the Discussion�

All Models Are Incomplete

Disagreement Persists

Among Experts

My Experiential Background:�College-Level Solo Voices

Classical Style

4 of 20

Terminology Salad�

William Vennard:

Zacconi (1596): Voce di petto, voce di testa

Behnke (1886): Lower thick, upper thick, upper thin, small

Van den Berg (1963): Chest, head or mid, falsetto, Strohbass, whistle

Vennard (1967): Chest, middle, head (SSA) or chest, head falsetto (TBB)

Heavy Mechanism vs. Light Mechanism

Hollien (1974): Pulse, model , loft

MIller (2000): Chest, middle, upper, flageolet (SSA) or Chest, full head, falsetto (TBB)

Roubeau (2009): M0 (fry), M1 (chest), M2 (falsetto), M3 (whistle)

Source: Christian T. Herbst. Registers - The Snake Pit of Vocal Pedagogy, Part 1. Journal of Singing. Nov/Dec 2020. p. 175.

5 of 20

What IS a Vocal Register?�

Manuel Garcia II (1847)

A series of consecutive and homogenous tones going from low to high, produced by the development of the same mechanical principle, and whose nature differs essentially from another series of tones, equally consecutive and homogenous, produced by another mechanical principle.

Scott McCoy: Your Voice, An Inside View

3rd Edition, Inside View Press, 2019. p. 230

Contiguous Pitches

Produced in Same Physiological Manner

Share the Same Basic Timbre

6 of 20

Mechanical / Muscular Aspects�

MODE 1 / CHEST / “STEAK”

Thyroarytenoid muscle dominant

Vocal folds shorter/thicker

Cover, body, and muscle layers vibrate

More horizontal spectral slope

Longer closed phase

Images: Titze, Ingo and Verdolini Abbott - via Ragan, Kari. A Systematic Approach to Voice: The Art of Studio Application. Plural Publishing. 2020. p. 118

MODE 2 / HEAD/FALSETTO / “PAPER”

Cricothyroid muscle dominant

Vocal folds longer/thinner

Cover and edge vibrates

Steeper spectral slope

Shorter closed phase

7 of 20

Look and Listen�Mechanics: Vocal Fold Contact Time

EGG - Electroglottograph

Sends electrical pulse across glottis. Tracks contact of vocal folds each cycle of vibration.

Baritone (Mode 1) vs Treble (Mode 2)

Contact Quotient: 50-70%

Contact Quotient: 30-40%

Closing Phasease

Closing Phasease

Vocal Folds Touching

Vocal Folds Touching

Opening

Phasease

Opening

Phasease

Glottis Opense

Glottis Opense

8 of 20

Look and Listen�Acoustics: Relative Strength of Upper Overtones

Spectral Slope/Tilt/Roll Off: Rate at which higher harmonics decrease in intensity.

Mode 1:

Shallower Spectral Slope

Mode 2:

Steeper

Spectral Slope

Amplitude

(dB)

Frequency

Hz

Higher frequency harmonics have more amplitude in Mode 1 and less amplitude in Mode 2

9 of 20

Laryngeal Registration Exercises�

Simple Registration Switch Exercise - Bel Canto Boot Camp

Source: Rachelle Jonck and Derrick Goff. The Vaccai Project: A practice diary exploring the historical performance practice of the bel canto style inspired by the lessons of Nicola Vaccai. Bel Canto Boot Camp. 2022, p. 28.

10 of 20

Laryngeal Registration Exercises�

More from Bel Canto Boot Camp Advanced Switch Exercise (treble)

Yodel Exercise (baritone key)

: �

Source: Rachelle Jonck and Derrick Goff. The Vaccai Project: A practice diary exploring the historical performance practice of the bel canto style inspired by the lessons of Nicola Vaccai. Bel Canto Boot Camp. 2022. p 73, 87

11 of 20

Laryngeal Registration Exercises�

Registration Exercises - Kari Ragan

Head Voice Isolation - Sing Do, re, mi, re do on /u/ piano, then /o/ or /a/ forte. Begin on C5.

Chest Voice Isolation (trebles) - On /væ/: Speak four quarter notes. Find brassy, forward, megaphone forward resonance. Then sing do, re, mi, re do, starting on A3. Progres to ascending broken thirds on same syllable.

Blend - Sing a five-note descending stepwise pattern on /u/ followed by /o/, /i/ and /a/. Allow registration to change from head to chest. Begin on A4.

Source: Kari Ragan: ASystematic Approach to Voice: The Art of Studio Application, 2020. Plural Publishing. p. 130, p. 139, p. 135.

12 of 20

Let’s Complicate the Model�

Source: Christian Herbst and Jan Svec

MODE

TWO

MODE

ONE

Thin

Thick

Weaker

Adduction

Stronger

Adduction

Witchy Voice

Seal Sounds

Mooing

Round Vowels

SOVTEs

Humming

13 of 20

Acoustic Aspects�Timbre Perception - Psychoacoustics

Auditory Roughness: Perceived buzziness in the timbre. Lower pitches tend to have more auditory roughness / buzz/ brassiness. Pitches sung with greater auditory roughness are perceived as “chestier” regardless of laryngeal function.

Higher pitches tend to have less auditory roughness because there are fewer closely clustered harmonics above the fundamental. Pitches sung with less auditory roughness are perceived as “headier” and more pure/smooth regardless of laryngeal function.

Source: Ken Bozeman. The Case for Acoustic Registers. Journal of Singing. November/December 2022. 181-187. KenBozeman.com Logarithmic Power Spectrum. Ian Howell: Parsing the Spectral Envelope. PhD Dissertation, New England Conservatory. 2016.

14 of 20

Acoustic Aspects�Tone Color and Emotional Affect

Absolute Spectral Tone Color (Chart): Frequency ranges are perceived as having vowel like qualities.

Sources: Ian Howell. Parsing the Spectral Envelope. www.IanHowellCountertenor.com

Ken Bozeman. www.Ken Bozeman.com: Chiaroscuro Whisper Vowel Modeling.

Affects for Cultivating Upper Overtone Colors (Chest/Buzz)

  • Arrogance
  • Skepticism / Disbelief
  • Something Smells Bad

Affects for Cultivating Lower Overtone Colors (Head/Smooth)

  • Aw! Cute puppies
  • Empathy
  • Mischief / Flirtation (MORE)

15 of 20

Acoustic Aspects�Formants, Resonances, & Vowels (Oh My!)

Resonance: An intrinsic property of a vocal tract that can boost certain frequency ranges. Changes when vocal tract shape changes.

Formant: The boosted resonances in the radiated sound spectrum. First two influence vowels. Top three influence carrying power.

ACOUSTIC REGISTRATION (Bozeman)

Open Timbre: Two or more harmonics below first formant.

Close Timbre: One harmonic below first formant.

Whoop Timbre: Zero harmonics below first formant.

Let’s look at it: KenBozeman.com, Listen with Madde Synthesizer.

Sources: Ian Howell. Parsing the Spectral Envelope. www.IanHowellCountertenor.com

Ken Bozeman. www.Ken Bozeman.com. Voice Pedagogy Resources.

16 of 20

Look and Listen�Acoustic Registration /a/ vowel

Sources: Ian Howell. Parsing the Spectral Envelope. www.IanHowellCountertenor.com

Ken Bozeman. www.Ken Bozeman.com. Voice Pedagogy Resources.

Open Timbre

Close Timbre

Consistent Shallow Spectral Slope

First

Formant

Close Timbre

Whoop

Timbre

17 of 20

Application: Vowel Choices�

ACOUSTIC RESONANCE STRATEGIES

Acoustic “Chestiness”: Choose vowels with higher first formant frequencies, like /a/ /ɛ/ and /ɔ/. More harmonics below first formant will create more open timbre.

Acoustic “Headiness”: Choose vowels with lower first formant frequencies like /i/ /u/ and /o/. Fewer harmonics below first formant will create a more closed or whoop timbre.

18 of 20

More Nuanced Models�

Ragan, Kari. A Systematic Approach to Voice: The Art of Studio Application. Plural Publishing. 2020. p. 119

19 of 20

Take Aways�

Registration is Complicated!

  • All models are incomplete.
  • The singing voice is a non-linear system.
  • There are many valuable, research-informed models.

Experiment with Laryngeal Function

  • Registration isolation and alternation to define feelings of mode 1 and mode 2 without holding larynx.
  • Explore adduction vs. flow in both chest and head function; encourage a firm zip-up or adduction in head and allowing more airflow / less pressure to find light chest function.

Playing With Acoustics Can Really Open Up Options

  • Auditory Roughness - Train ears to listen for the buzz / smoothness.
  • Use affect to play with (absolute spectral) tone colors.
  • Choose vowel templates for registration goals.

20 of 20

Resources

NATS Science-Informed Pedagogy

www.KenBozeman.com

www.IanHowellCountertenor.com

VoceVista Software

Madde Synthesizer

Kari Ragan’s Book

See Articles in Journal of Singing By:�Christian Herbst & Jan Svec

Kenneth Bozeman