This trend and product overview is focused on the exploding number of small and micro-sized “line array” products. The number of products available today is growing at such an incredible rate that you must consider this system type when evaluating possible products for the vast majority of spaces. Very few facilities are truly large enough to require the deployment of the very large array products. For the purposes of this article and roundup we defined subcompact arrays as those using primary or LF drivers of 8 inches in size or less. We defined micro-sized arrays as those using drivers of 5 inches or smaller.
Once upon a time, say half a century ago, what the industry now refers to as “line-arrays” made their first appearance in the sound reinforcement world. Back then they were really vertical column arrays, employing the “steering” or “focusing” effects of multiple drivers grouped or stacked in a narrow vertical box.
They were able to produce their control of acoustic output using a combination of electrical energy tapering and the immutable physics of combining the multiple acoustic sources. The electrical tapering was created using good old fashioned physical components (you may remember things like resistors, capacitors, chokes and similar devices), which determined how much power was being sent to which drivers, thus creating what is commonly called a beam effect.
By limiting the vertical pattern these systems could keep energy off ceilings and floors and help mitigate the amount of energy being bounced around and reflected within the space.
Products designed by people such as Rudy Bozak (who made the only broadbandwidth-capable column at the time) and David Klepper along with many others were primarily used as speech-only reinforcement devices in difficult, reverberant or other problematic acoustic spaces to provide, improved intelligibility of the spoken word.
After a while those early column systems sort of faded into the background until in the mid 1990’s when France’s Christian Heil’s L-Acoustics large scale V-DOSC line array loudspeakers made their appearance in North America, first in the concert sound industry and later in installation applications. These reminded the industry that higher output levels and more balanced frequency responses could be produced with just a few drivers in a horizontal “linear array” alignment. Although a number of one-off systems had been produced and installed, V-Dosc was the first officially “commercial” product to hit the streets. Many other soon followed.
For those who want a slightly more technical explanation, what happens is that “line arrays, or more properly “line sources,” create a pie-wedge-shaped wavefront pattern. Think of it as a section of a cylinder of sound. Like any cylinder the bigger you make it, the wider the leading edge becomes (i.e., the surface area of the wave expands and doubles in area as the distance from the origin point doubles). Thus the primordial but still valid inverse square law