Helmholtz Resonators, Quarter Wave Tubes, Perforated Acoustic Liners, and Passive Acoustic Radiators are the tuned acoustic absorbers (band-reject acoustic filters) commonly used in mitigating narrow-band noise.

Examples of such mitigation applications include, but are not limited to quieting the tonal noise at the blade passage frequency of an axial fan and dampening a standing wave of an enclosure (or a duct).

Optimal design of tuned acoustic absorbers for maximum absorption requires a thorough understanding of the effects of geometry variations on their performance. DEICON has developed a finite element analysis (FEA) based tool for optimally designing tuned absorbers. In addition to the synthesis of such absorbers, this in-house numerical tool allows for analysis/evaluation of tuned absorption mechanisms in any acoustic environment. The FEA based design tool uses acoustic impedance boundary conditions to account for damping realized by the acoustic treatment.

DEICON designs and fabricates tuned acoustic absorbers, of various kinds, for different narrowband sound absorption applications.

Passive Tuned Acoustic Absorbers

  • Helmholtz Resonators
  • Quarter Wave Tubes
  • Perforated Acoustic Liners
  • Passive Acoustic Radiators

Learn About Tuned Mass Dampers


Vibration Control of a Grand Ballroom Floor System Using Tuned Mass Dampers

Floor vibration of a grand ballroom subject to crowd loading is mitigated using tuned mass dampers along with stiffening.

Viscous Damping Devices Rebuilt

After 20+ years of operation, the 8 viscous damping devices of the 4 tuned mass dampers needed to be rebuilt. DEICON was commissioned to do this task by changing all the components of the viscous damping devices with their equivalent brand-new ones, testing the rebuilt units, and adjusting their damping coefficients.

Active Boom Noise Abatement in a Sport Utility Vehicle (SUV)

An active boom noise control solution is developed to add acoustic damping to the low-frequency standing waves inside the cabin of a large SUV to quiet its tonal persistent boom noise.