WOBBLbox.step

where do standing waves form in the air inside the box below 1 kHz?

Sound report
2026-10-15 19:03
OK

The air has 4 standing wave modes below 1000 Hz, the lowest at 331 Hz and the next at 847 Hz.

lowest mode
331 Hz
modes
4 below 1000 Hz
air volume
10.4 L
close pairs
0

Confidence low

  • mesh convergence failed: the first 4 modes moved at most 2.9% on the finer mesh

Simulation

The first mode shapes on a slice
The first mode shapes on a slice
Mode frequencies
Mode frequencies

Checks

statuscheckresult
failmesh convergencethe first 4 modes moved at most 2.9% on the finer mesh
passmode count4 modes below 1000 Hz, where Weyl's formula for this volume and surface expects about 4

Assumptions

  1. Sound hard walls with no absorption, air at 20 C (343 m/s). Real walls damp the modes, and the frequencies hold to about a percent.
  2. The air is the cavity inside 'box', taken from the CAD.