Design Principles:
• Calculator distributes frequency range logarithmically across chambers
• Lower frequencies generally require smaller total opening area, longer effective necks, or larger chamber volume
• Higher frequencies generally require larger total opening area, shorter effective necks, or smaller chamber volume
• The optimizer checks hole diameter and neck length against the Helmholtz resonance equation
• Neck lengths are selected within the available construction depth
Optimization Features:
• Uses the available depth as chamber volume, then optimizes each chamber's hole and neck dimensions
• Shows achieved resonance frequency and target error for each chamber
• Includes end correction for the effective neck length
• Attenuation is an estimate derived from peak absorption, not a guaranteed room SPL reduction
• Easy to construct with standard woodworking tools
How the Helmholtz resonator calculator works
Target frequency range, panel perforation, chamber count, and depth limits drive optimized chamber dimensions and hole layouts for perforated-panel or boxed Helmholtz absorbers used in architectural acoustics.
Key terms
Helmholtz resonator - mass of air in a neck plus spring of cavity volume resonates at a set frequency.