Main Content

John Large Vocal Arts Laboratory

In the John Large Vocal Arts Laboratory, students learn the acoustic parameters of pitch control, fundamental frequency and harmonic partials that determine vocal timbre, vowel definition, the presence of vibrato, legato and linguistic accuracy by listening to and observing phonations from their own lessons and performances as well as by studying live phonations in the laboratory.

With the laboratory’s real-time spectrography, the voice professor and the applied voice student, the voice therapist and the patient, the actor and the instrumentalist have numerous analytical tools for understanding the complex acoustical data of spoken, sung and played sound. A classically trained singer’s spectrogram has unique features that are easily visible: the singer produces not just a single note, but a simultaneous sounding of selective overtones that define the vowel and allow the voice to carry over a large orchestra in a 3,000-seat performance hall. These features can be observed, as can the consistency of richness and color through the dynamic and pitch range of the voice.

Visible read-outs of the spectrogram include:

Frequency (cps or Hertz)
The vertical axis shows the fundamental frequency and all the overtones (partials) generated by a single tone. The horizontal axis shows time. Real-time spectrography graphs the sound patterns exactly as they are produced by the singer or speaker.

Acoustic energy
Acoustic energy is measured from light to dark, with dark tracings representing higher acoustic energy. Patterns of acoustic energy display the balance of tonal color, vowel definition, clarity of sound onset and the presence of the singer’s formant constant between 2800-3500 Hertz in sound with the carrying power necessary for success in performance. The “ring and warmth” characteristic of great voices including Jussi Bjoerling, Renata Tebaldi and Luciano Pavarotti can be analyzed. The student learns that formant balance, rather than sheer muscular effort, produces increased decibel output. Extraneous muscle tension only dampens or inhibits sound.

Continuance (Legato)
Legato, the seamless sung vocal line without noise or interruption, is easily visible when the student produces a spectrograph without stops or inconsistencies, full of contiguous lines of similar acoustical data. For both singers and speakers, vowel and consonant duration can be observed with great clarity, immediately drawing the student’s attention to the common (and frequently unconscious) pattern of forming the consonant prematurely.

Vibrancy (Vibrato)
Regularity in cycle and pitch excursion of vibrato are easily discerned through spectral analysis. Vibrato rate and straight tone can also be immediately discerned.

Registration/vowel modification
Acoustical data of all singing registers — chest, head, and falsetto — are easily apparent. To control consistency of timbre across registration events, the student can check to see if the formants remain in a consistent pattern.

Speech vs. singing
The student can notice the enormous differences in the acoustical energy and duration of the singing and speaking voice. In some instances, the speech of a singer exhibits greater acoustical energy than the singing voice. This immediately shows the student that certain modifications must take place to correct the imbalance.

Vowel definition
Split screen audio-visual allows performers to see both themselves shaping an English or foreign language phoneme and the resultant spectrogram, which demonstrates the accuracy of the effort. The vowel chart mode, which displays first and second formant positions also helps both singers and speakers with vowel clarity and assists in dialect reduction.

Using a camera to film your posture is an invaluable tool for improving body alignment, extraneous movement of the head, jaw, shoulders, lips and neck. Dramatic skills, facial expression and stance, can also be improved through the use of the camera in the studio and the laboratory.


For more information, contact:
Dr. James Rodriguez
Assistant Professor of Voice