Room Axial Modes
Find the first resonant bass modes of a rectangular room.
About Room Axial Modes
Every room dimension has a fundamental resonance at a frequency set by half its wavelength, with the longest side ringing lowest. Bass builds up unevenly at these modes, so knowing them guides speaker and listening positions plus bass trap placement.
Formula
Room Axial Modes
Axial mode = speed of sound / (2 x dimension)
- axial mode
- A resonance along one pair of parallel walls
Worked example
With the default values below, Room Axial Modes returns Lowest Mode of 34.3. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Room lengthminimum 0.1 m
- 5 m
- Room widthminimum 0.1 m
- 4 m
- Room heightminimum 0.1 m
- 2.5 m
Results
- Length Mode
- 34.3 Hz
- Width Mode
- 42.9 Hz
- Height Mode
- 68.6 Hz
- Lowest Mode
- 34.3 Hz
Step by step
- 1Values used
- 2Room Axial Modes
- 3Lowest Mode= 34.3 Hz
- 4Length Mode= 34.3 Hz
- 5Width Mode= 42.9 Hz
- 6Height Mode= 68.6 Hz
Assumptions and limits
- The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 1 decimal place, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Room Axial Modes calculated?
Axial mode = speed of sound / (2 x dimension) Every room dimension has a fundamental resonance at a frequency set by half its wavelength, with the longest side ringing lowest.
Why does Room Axial Modes matter?
Bass builds up unevenly at these modes, so knowing them guides speaker and listening positions plus bass trap placement.
What values do I need to enter?
This calculator takes 3 inputs: Room length, Room width, Room height. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.