ToolsSound, propagation & hearing
A & C frequency weighting
A- and C-weighting at any frequency, with curves and weighted levels.
Hz
dB(Z)
A-weighting
-19.1dB
C-weighting
-0.3dB
Weighted level
70.9dB(A)
Weighted level
89.7dB(C)
IEC 61672-1 weighting curves. A-weighting roughly follows the ear at low levels and is used for noise limits; C-weighting is flatter and is used for peak and loud-music measurements. Neither describes loudness at high levels well.
How it works
Sound level meters apply weighting filters to approximate how the ear responds. A-weighting strongly reduces low frequencies and is used for most noise regulations; C-weighting is nearly flat and is used for peak and high-level measurements.
Formulas
- A(f) = 20 · log₁₀ R_A(f) + 2.00 dB
- C(f) = 20 · log₁₀ R_C(f) + 0.06 dB
Found a mistake or have an idea for this tool?
Suggest a change