PPolySim OS

Helmholtz Resonator

Blow across a bottle and it hums a single note. That is a Helmholtz resonator — a mass of air in the neck bouncing on the springy air in the cavity.

Helmholtz ResonatorLive

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Presets

Blow across a bottle and it sings at its Helmholtz frequency. The plug of air in the neck acts as a mass and the air in the cavity as a spring, giving f = (c/2π)√(A/VL). Bigger cavities and longer necks lower the pitch — the principle behind bass ports, mufflers, and ocarinas.

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Data Inspector

Resonant frequency167 Hz
Wavelength2.05 m
Cavity500 cm³

Governing equation

Reading this result: This cavity sings near 167 Hz — a 2.05 m wavelength. Enlarge the cavity or lengthen the neck and the pitch drops, because both add to the mass-on-a-spring that sets the tone.

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How it works

A Helmholtz resonator behaves like a mass-spring oscillator: the plug of air in the neck is the mass and the compressible air in the cavity is the spring, resonating at f = (c/2π)√(A/VL). Larger cavities and longer necks lower the pitch. The effect drives bass-reflex speaker ports, engine mufflers, and ocarinas.

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Frequently asked questions

Is this Helmholtz resonator frequency tool really free?
Yes. Helmholtz Resonator runs entirely in your browser using your device's own compute, so local use is free forever. You only pay Compute Tokens if you scale a job to the cloud.
Do I need to install anything?
No. Everything runs client-side in a modern browser — no downloads, no license, no account required to start.
Can I save or share my simulation?
Create a free account to save projects, and use a shareable embed or minted DOI to publish a live, interactive version anywhere.
How accurate are the results?
The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.