Wundt built drop-based devices isolating intensity from frequency for controlled study.

Evidence

Yet, one of Helmholtz’s students, Wilhelm Wundt (1832–1920), did not let these limitations stymie his interest in sound perception and, in particular, the perception of sound intensity. Notably, Wundt developed many instruments that allowed him to measure the perception of sound in a controlled way. His sound pendulum and falling phonometer allowed him to alter sound intensity without changing the frequency characteristics of a sound (Schick, 2004). Examples of these devices are shown in Figures 1–3 and 1–4. Both of these devices functioned by dropping an object that struck a panel. The height of the object would determine the intensity of the sound generated when it hit the panel. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 74

Categorization

• QUESTION: How exactly did a dropped pendulum/pnometer achieve constant-frequency variable-intensity control, when other methods could not? The mechanics matter for understanding the experimental constraint.