Room Modes Calculator
Calculate axial, tangential and oblique room modes from room dimensions and see where bass peaks and nulls will appear.
Inputs
Lowest modes
| Freq | Mode (L,W,H) | Type |
|---|---|---|
| 33.0 Hz | (1, 0, 0) | Axial |
| 42.9 Hz | (0, 1, 0) | Axial |
| 54.1 Hz | (1, 1, 0) | Tangential |
| 66.0 Hz | (2, 0, 0) | Axial |
| 68.6 Hz | (0, 0, 1) | Axial |
| 76.1 Hz | (1, 0, 1) | Tangential |
| 78.7 Hz | (2, 1, 0) | Tangential |
| 80.9 Hz | (0, 1, 1) | Tangential |
| 85.8 Hz | (0, 2, 0) | Axial |
| 87.4 Hz | (1, 1, 1) | Oblique |
| 91.9 Hz | (1, 2, 0) | Tangential |
| 95.2 Hz | (2, 0, 1) | Tangential |
| 98.9 Hz | (3, 0, 0) | Axial |
| 104.4 Hz | (2, 1, 1) | Oblique |
How it works
Sound waves reflect off the walls of a room. At certain frequencies, a wave that bounces back and forth fits exactly between two walls, forming a standing wave (a room mode). At those frequencies the bass gets louder at some spots (pressure peaks) and nearly disappears at others (nulls), which is why one seat in a room can have booming bass and another thin bass.
f(nx, ny, nz) = (c / 2) · √( (nx/L)² + (ny/W)² + (nz/H)² ) c = 343 m/s n = 0, 1, 2, 3 … (at least one n ≠ 0)
Axial modes (only one n ≠ 0) bounce between a single pair of walls and are the strongest. Tangential modes involve four walls and are about 3 dB weaker; oblique modes involve all six surfaces and are about 6 dB weaker. Below the lowest mode there are no resonances at all, in a closed room the bass simply rises (“room gain”).
Good room ratios spread modes evenly. Dimensions that are equal (a cube) or integer multiples of each other stack modes on the same frequency, producing a huge peak. If the room is a problem, try moving the sub (modes change location), adding multiple subs, using EQ to cut peaks (never to fill nulls), and bass traps in corners.