Base width

from Wikipedia, the free encyclopedia

The basic width is the real or virtual distance between the two speakers required for stereophonic reproduction. The distance between two microphones used for stereophonic recording is also referred to as the base width.

Stereophonic playback

The basic width of the two speakers for stereo playback, i.e. H. the distance between the two speakers is called speaker base b . The base width is of fundamental importance for the design of the stereo listening surface and thus for the reproduction quality. The basic rule is: best listening distance = 0.866 × base width; With a base width of 2.50 m, the listening distance should be 2.17 m. This results in the equilateral 60 ° stereo triangle .

The basic width to be selected depends on the size of the display room. In large rooms, a larger base width and thus an increased listening distance is favorable, while small rooms only allow a smaller base width and thus force the listener to approach the playback loudspeakers more closely. There are no precise rules for setting up stereo playback. The localization of the direction of the phantom sound source on the loudspeaker base is referred to as the direction of the auditory event .

This arrangement of the stereo speakers is probably due to the best seats when attending an orchestra concert, where there is a similar listening angle area. However, stereophony often has little to do with the naturalness of sound reproduction, since a stereophonic recording is often created by recording individual voices with a microphone and only then more or less subjectively mixed to a stereo signal.

The base width of loudspeakers that are closely spaced (for example a radio recorder ) can be virtually widened electronically ( base widening or base width enlargement ); see Stereo in Practice .

Stereophonic recording

The basic width of the two microphones, which are used, for example, according to the AB method in runtime stereophony , is the distance between the two microphones; it is called microphone base a . Even with the Äquivalenzstereofonie one speaks of the base width of the main microphone; for example ORTF a = 17 cm.

The base width is of great importance because it also determines the recording area of the microphone system and the imaging width on the loudspeaker base. For mapping completely sideways from the direction of a loudspeaker, a transit time difference Δ L of 1 to 2 ms is required for the sum localization , depending on the impulse content of the signals. The microphone base of the microphone system decides the time difference resulting from the sound incidence angle , and this time difference determines the direction of the auditory event of the phantom sound sources heard on the loudspeaker base.

literature

  • Michael Dickreiter, Volker Dittel, Wolfgang Hoeg, Martin Wöhr (eds.): Manual of the recording studio technology . 2 volumes. 8th, revised and expanded edition. Walter de Gruyter, Berlin / Boston 2014, ISBN 978-3-11-028978-7 .

See also

Web links