User Manual

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Line-Array Speakers
The term “line-array” is used to describe a speaker system having multiple speaker units with the same characteristics
arranged vertically to emulate a linear acoustical source. In contrast to standard speakers, which operate as a point
source from which sound propagates over a wide dispersion angle in both the horizontal and vertical planes, the sound
propagating from a line-array speaker disperses very little in the vertical plane. One of the advantages of these systems
is, therefore, lower attenuation of sound pressure over distance.
Conceptual view of sound propagation
Standard speaker (point source) Line-array speaker (line source)
Sound waves propagate in the shape of a sphere,
spreading out horizontally and vertically. With every
doubling of distance, the surface area of the propagation
front increases by a factor of four. In other words, the
sound intensity per unit area drops by a factor of four,
and the sound pressure level attenuates by 6 dB.
Sound waves propagate in the shape of a cylinder,
spreading out horizontally but not vertically. With every
doubling of distance, the surface area of the propagation
front increases by a factor of two. In other words, the
sound intensity per unit area drops by a factor of two,
and the sound pressure level attenuates by 3 dB.
Propagation
surface
A x 4
Propagation
surface
A
Distance D x 2
Distance D
Propagation
surface
A
Propagation
surface
A x 2
Distance D
Distance D x 2