Vocal Resonance: How to Feminize Your Voice | MtF Transgender

The sound of our voice is produced through a complex interplay of vocal fold vibration, airflow, and vocal tract filtering. For transgender women seeking to feminize their voices, understanding the physics behind these mechanisms is essential. 

This guide will break down the acoustics of vocal production and how to leverage them to alter vocal resonance. 

Read on to learn about how vocal resonance works and how to feminize your voice. Also, the source-filter theory of speech, the harmonic series, and how to shift your voice's timbre through vocal tract modifications. 

The Three Parts of Your Voice

Your voice is made up of three main components:

  • The power source - your airflow from your lungs
  • The source tone - the sound your vocal folds make as they open and close
  • The filter - how your vocal tract shapes the source tone into different sounds

As you exhale, the vocal folds in your larynx open and close rapidly, interrupting the airflow and creating vibrations.

This vibrating airflow then resonates through your vocal tract, which acts as a filter to shape the source tone into different vowel and consonant sounds.


The Harmonic Series and Source Tone

The sound produced by your vibrating vocal folds is called the source tone, and it contains a spectrum of sound frequencies called the harmonic series.

This is a natural acoustic phenomenon - any vibrating object produces a series of frequencies at whole number multiples of the lowest "fundamental" frequency.

When you phonate, your vocal folds vibrate at a certain frequency, say 100Hz. This generates a harmonic series with frequencies at 100Hz, 200Hz, 300Hz, 400Hz etc. The relative amplitudes of the harmonics give your source tone its unique timbre.

This raw source tone is the same for everyone. All vocal differences come from how your vocal tract filters shape it.

Vocal Tract Resonance and Filtering

Your vocal tract consists of your larynx, pharynx, and oral cavity. This system of tubes acts like an acoustic filter on the source tone.

Certain frequencies will resonate more strongly in the vocal tract depending on its shape and length. This resonance reinforces some harmonics over others, changing the source tone into different vowel sounds.

Longer vocal tracts have lower resonant frequencies, making the voice sound darker and more masculine. Shorter vocal tracts resonate at higher frequencies, making the voice lighter and more feminine.

Factors like tongue position, mouth shaping, and larynx height all modify the size and shape of your vocal tract, shifting where it resonates and filtering the source tone. This is how we create different speech sounds.


Changing Vocal Resonance with Voice Training

The goal of voice feminization is to reduce the size of your vocal tract to shift resonance to higher frequencies. This is done through larynx height elevation, pharyngeal constriction, less oral space, and other adjustments.

With consistent training and practice, transgender women can reshape their vocal tract to filter out lower frequencies, reduce the sense of chest resonance, and develop a lighter, brighter voice.

Understanding the acoustics behind your voice gives you a predictable model to follow. By targeting the physics of vocal fold vibration and vocal tract filtering, you can make reliable changes to your vocal resonance and timbre.

Vocal Resonance: How to Feminize Your Voice: Conclusion

In conclusion, vocal resonance is a crucial aspect of voice production for transgender women seeking to feminize their voices. Understanding the physics behind vocal production and vocal tract filtering is essential for achieving the desired results.

By targeting the source tone, harmonic series, and vocal tract resonance, transgender women can reshape their vocal tract to filter out lower frequencies, reduce chest resonance, and develop a lighter, brighter voice.