Calculateur de Résolution CNA — Formule
## What is Total Harmonic Distortion?
THD measures the ratio of harmonic content to the fundamental, indicating how much a device distorts a pure signal.
### Formula
**THD = sqrt(V2^2 + V3^2 + V4^2 + V5^2 + ...) / V1 x 100%**
Where V1 is the fundamental and V2, V3... are harmonic amplitudes.
### Quality Benchmarks
- < 0.01%: Audiophile/measurement grade
- 0.01-0.1%: High fidelity
- 0.1-1%: Consumer electronics
- > 1%: Noticeable distortion
THD measures the ratio of harmonic content to the fundamental, indicating how much a device distorts a pure signal.
### Formula
**THD = sqrt(V2^2 + V3^2 + V4^2 + V5^2 + ...) / V1 x 100%**
Where V1 is the fundamental and V2, V3... are harmonic amplitudes.
### Quality Benchmarks
- < 0.01%: Audiophile/measurement grade
- 0.01-0.1%: High fidelity
- 0.1-1%: Consumer electronics
- > 1%: Noticeable distortion
Exemple Résolu
Fundamental at 1.0 V with harmonics at 0.02, 0.015, 0.005, 0.003 V.
- RSS = sqrt(0.02^2 + 0.015^2 + 0.005^2 + 0.003^2)
- = sqrt(0.0004 + 0.000225 + 0.000025 + 0.000009) = sqrt(0.000659)
- = 0.02567 V
- THD = 0.02567 / 1.0 x 100 = 2.567%
- THD dB = 20 x log10(0.02567) = -31.8 dB