Related Experiment Video
Updated: Aug 21, 2026

Hemi-laryngeal Setup for Studying Vocal Fold Vibration in Three Dimensions
Published on: November 25, 2017
Seeing a voice: Rudolph Koenig's instruments for studying vowel sounds
1Dibner Institute for the History of Science and Technology, MIT, USA.
Abstract:
The human voice was one of the more elusive acoustical phenomena to study in the 19th century and therefore a crucial test of Hermann von Helmholtz's new theory of sound. This article describes the origins of instruments used to study vowel sounds: synthesizers for production, resonators for detection, and manometric flames for visual display. Instrument maker Rudolph Koenig played a leading role in transforming Helmholtz's ideas into apparatus. In particular, he was the first to make the human voice visible for research and teaching. Koenig's work reveals the rich context of science, craft traditions, experiment, demonstration culture, and commerce in his Paris workshop.
More Related Videos
Related Concept Videos
Anatomy of the Ear
Perception of Sound Waves
The pitch of a sound depends on the frequency and the pressure amplitude of the source. Two sounds of the same frequency...
The Auditory Ossicles
The aptly named stapes look very much like a stirrup. The three ossicles are unique to mammals, and each plays a role in...
Auditory Perception
Hearing
Perceiving Loudness, Pitch, and Location
Place theory, or place coding, suggests that different pitches are heard because various sound waves activate specific locations along the cochlea's basilar membrane. The brain determines the pitch of a sound by identifying...

