External voltage distance

The external voltage distance is the ratio of useful voltage to external voltage of a transmission system for acoustic signals. The external voltage is a noise level caused by system-related sources of interference in the transmission system. ${\displaystyle D_{f}}$

To determine the external voltage distance, the external voltage is related to the useful voltage ( useful electrical signal ) of the transmission system in accordance with the following relationship , logarithmized and specified in d B :

${\displaystyle {\frac {D_{f}}{\mathrm {dB} }}=20\cdot \ lg\ {\frac {U_{n}}{U_{f}}}\,}$.

Mean:

• U _{n is} the useful voltage
• U _{f is} the external voltage.

The external voltage is measured using a linear amplifier that covers the entire transmission range of the system, i.e. H. without rating filter . In particular, the mains hum is fully effective.

The noise voltage measured with the weighting filter is called the noise voltage .

See also

• S / N ratio
• RMS value quasi- peak value
• Signal to noise ratio

literature

• Gustav Büscher, A. Wiegemann: Little ABC of electroacoustics. 6th edition, Franzis Verlag, Munich, 1972, ISBN 3-7723-0296-3
• Hubert Henle: The recording studio manual. 5th edition, GC Carstensen Verlag, Munich, 2001, ISBN 3-910098-19-3