Statistical guideline factor

The statistical directivity factor _st (gamma) (also called directivity deviation factor or statistical directional factor ) is one of the variables used in acoustics to describe the directional characteristic of a sound source . It is defined as the ratio of the effective value of the sound pressure in a certain direction of radiation and distance to the effective value of the sound pressure averaged over all radiation directions at the same distance: ${\displaystyle \Gamma }$ ${\displaystyle (\varphi ,\theta )}$

${\displaystyle \Gamma _{st}={\frac {{\tilde {p}}(\varphi ,\theta )}{\sqrt {\frac {}{{\tilde {p}}^{2}(\varphi ,\theta )}}}}}$.

The statistical directivity factor is therefore dependent on the direction of radiation, values> 1 stand for preferred radiation directions.

In an analogous manner, receivers for sound such. B. microphones , specify a statistical directivity factor.

The degree of directivity is the square of the statistical directivity factor, the directivity or directivity is the corresponding dimension with the auxiliary unit of measurement decibel :

${\displaystyle G=20\lg \Gamma _{st}\;\mathrm {dB} .}$

See also

• Degree of bundling
• List of audio terms

literature

• Michael Dickreiter, Volker Dittel, Wolfgang Hoeg, Martin Wöhr, “Handbuch der Tonstudiotechnik”, 7th completely revised and expanded edition, published by the ARD.ZDF medienakademie, Nuremberg, 2 volumes, publisher: KG Saur, Munich, 2008, ISBN 3-598-11765-5 or ISBN 978-3-598-11765-7

Web links

• Statistical guideline factor as DEGA recommendation 101 (PDF file; 1016 kB)