A hollow vessel of the type used by Von Helmholz in the 1850s to demonstrate resonating cavities.
Source: http://en.wikipedia.org/wiki/Helmholtz_resonance
The Helmholz resonator describes the behaviour of air in a cavity. If the cavity or chamber is larger the volume of air is obviously larger. The "natural" soundwave in a particular sized chamber will have some fundamental frequency. The larger the chamber, the lower this "natural" soundwave pitch; the small the chamber, the higher the soundwave pitch.
In over-simplified terms, the difference between the Helmholz resonator and the Bernoulli effect is that the Bernoulli effect creates sound, while the Helmholz resonator amplifies it.
The behaviour of the Helmholz resonator is fairly obvious when, for example, the violin is compared to the double bass. The soundbox (chamber) of the double bass is much larger than that of the violin, so it is not surprising that the resulting dominant soundwaves are lower in pitch.
A hollow vessel of the type used by Von Helmholz in the 1850s to demonstrate resonating cavities.
Source: http://en.wikipedia.org/wiki/Helmholtz_resonance
What is known as the Helmholz resonator was first described by Hermann von Helmholtz in his book Die Lehre von den Tonempfindungen als physiologische Grundlage für die Theorie der Musik (On the Sensations of Tone as a Physiological Basis for the Theory of Music) published in 1863.
Hermann von Helmholtz (1821 – 1894)
Source: http://en.wikipedia.org/wiki/Hermann_von_Helmholtz