CHAPTER 5
CHAPTER 5: LINE ARRAYS AND SYSTEM INTEGRATION
HOW LINE ARRAYS WORK
Line arrays achieve directivity through constructive and destructive interference. For example, consider one loudspeaker with a single
Stacking two of these loudspeakers one atop the other and driving both with the same signal results in a different radiation pattern. At common points
a sine wave, there will be points where the cancellation is complete, which can be shown in an anechoic chamber. This is destructive interference, sometimes referred to as combing.
A typical line array comprises a line of loudspeakers carefully spaced so that constructive interference occurs
M’ELODIE CURVILINEAR ARRAY
The M’elodie loudspeaker employs a combination of drivers to enable you to optimize both coverage and directivity in a M’elodie line array system. To achieve optimal results, it is important to understand how these components work together.
In the horizontal pattern of an array of M’elodies, these horns work to produce a wide
■Minimize destructive interference between adjacent elements
■Promote coupling to throw longer distances
As more elements are arrayed in a vertical column, they project mid- and
■Wide angles: Curving a line array can aid in covering a broader vertical area.
■Narrow angles: Straightening a line array provides a longer throw and coverage that more closely matches that of the
Mid to Low Frequencies
For the mid to low frequencies, line arrays must be coupled together to narrow their vertical coverage and project mid and low energy to the far field. The directional control of the array depends on the length of the array (number of elements).
Directional control is achieved when the length of the array is similar or larger than the wavelength of the frequencies being reproduced by the array. As frequencies get lower and wavelengths get longer, the number of cabinets has a critical effect on the directional control. The number of array elements is very important: the more M’elodie loudspeakers used, the more directional the vertical beamwidth becomes at the lower frequencies. However, at low frequencies the splay angle between cabinets has little effect since the total length is not modified substantially.
High Frequencies
For high frequencies, M’elodie uses a very precise Constant Q horn — developed using Meyer Sound’s anechoic chamber — which provides a consistent beamwidth of coverage in the horizontal plane.
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