Additional Info

• ID Code: H3-41
• Purpose: Demonstrate the resonance behavior of a Helmholtz resonator.
• Description: The Helmholtz resonator is excited by an oscillator driving a small loudspeaker at about 250 Hz. Resonances in the system are sensed using a sound probe inserted into a small, rubber-padded opening on the resonator, and displayed on the oscilloscope.

  These sorts of globular resonators were used by Helmholtz in the nineteenth century, in the early days of acoustics experimentation. Before the development of spectrum analyzers and similar tools, he developed techniques to analyze the structure of sounds simply by holding a succession of resonators of different frequencies to his ear to pick out the components of complex sounds. The principle behind this is little different from twentieth century analog electronic frequency analyzers, which feed a signal from a microphone into a series of resonant circuits analogous to Herlmholtz's glass globes.

• Availability: Available
• References: REFERENCES: (PIRA 3D30.40)
• Loc codes: H3, ME2, ME3, OM1, OM2