Ringkammern

Ringkammern, also known as resonance chambers or Helmholtz resonators, are acoustic devices designed to amplify or absorb sound at specific frequencies. Their fundamental principle is based on the oscillation of air within a cavity connected to the outside by a narrow opening. This system acts like a mass-spring system, where the air in the opening acts as the mass and the air in the cavity acts as the spring.

The resonant frequency of a ringkammer is determined by the volume of the cavity and the dimensions of the opening, particularly its length and cross-sectional area. A larger cavity or a smaller opening generally leads to a lower resonant frequency. When sound waves at or near the resonant frequency strike the ringkammer, the air inside vibrates with a large amplitude, effectively absorbing the sound energy at that frequency. Conversely, if excited by an external source at its resonant frequency, the ringkammer can radiate sound.

Ringkammern are commonly found in musical instruments, such as guitars and violins, where they contribute to the instrument's tonal quality and volume. They are also employed in acoustic engineering for noise reduction and soundproofing applications, where they can be tuned to cancel out specific problematic frequencies. In some cases, multiple ringkammern with different resonant frequencies can be combined to achieve broadband sound absorption. Their design is relatively simple, making them an efficient and cost-effective solution for acoustic manipulation.