Difference tone factor

The difference tone factor is a dimensionless measure of nonlinear distortion . It describes the behavior of two tones that are sent into an amplifier . They come out again at the end, plus another tone that is the difference between the two original tones. The difference tone factor is already clearly perceptible below 0.1% and manifests itself in a "covered" sound. ${\displaystyle d}$

The difference tone factor indicates a ratio of two effective values , namely the effective value of the difference tones of two sinusoidal oscillations with the frequency difference Δ f = 80 Hz (70 Hz according to DIN 45403) to the effective value of the entire mixture at the output.

As with the distortion factor and the intermodulation factor, only individual distortion products are measured with the difference tone factor , namely the difference tone factors of the 2nd and 3rd order:

${\displaystyle d_{2}={\frac {U_{f_{2}-f_{1}}}{2\cdot U_{ges}}}\,}$

${\displaystyle d_{3}={\frac {U_{2f_{2}-f_{1}}+U_{2f_{1}-f_{2}}}{2\cdot U_{ges}}}\,}$

With

• U RMS value of the voltages
• f ₁ , f ₂ upper and lower measuring frequency
• U _tot total voltage at the output.

literature

• DIN IEC 60268-3: 2000, Bl. 3, Electroacoustic devices - Part 3: Amplifiers

See also

• Beat
• List of audio terms