Wavelength

λ = c / f

Log-log wavelength versus frequency chart from 20 Hz to 20 kHz with cabin-length, dash-width, door-width, and headrest-spacing reference lines — This chart keeps the relationship honest: every octave step halves wavelength. The horizontal guide lines show why cabin-length dimensions dominate deep bass while shorter vehicle dimensions matter more as frequency rises.

Frequency	Wavelength (at 20°C)
20 Hz	17.2 m (56 ft)
40 Hz	8.6 m (28 ft)
80 Hz	4.3 m (14 ft)
160 Hz	2.1 m (7 ft)
500 Hz	0.69 m (27 in)
1,000 Hz	0.34 m (13.5 in)
2,000 Hz	0.17 m (6.7 in)
4,000 Hz	0.086 m (3.4 in)
10,000 Hz	0.034 m (1.3 in)
20,000 Hz	0.017 m (0.67 in)

Practical implications:

Sound waves above ~1 kHz have wavelengths shorter than typical speaker separation distances — these frequencies are directional and imaging-sensitive
Crossover frequencies above 1 kHz require careful time alignment
Bass frequencies (below 200 Hz) have wavelengths longer than the cabin — they pressurize the whole space