Design Instruments; Lac - PROEL AXIOM - VERSION 2.0 Manual

4.2. DESIGN INSTRUMENTS

vertical array systems we use the centralized approach to sound reinforcement, and the modality which
allows the creation of a single, large source has already been treated in detail when we discussed
array-ability.
One of the great advantages of vertical array systems is the possibility to mould the angular coverage
on the vertical axis of the sound source with a certain degree of freedom, varying the curvature of the
array and the number of units employed in the array. Scalability faces a downward limit imposed by di-
rectivity control and by timbre balance, and an upward limit determined by weight and by the dimensions
of the array. The possible solutions between these two limits are many; therefore the system can be
adapted to a great variety of situations.
4.2 Design instruments
Once you have all information available on the coverage area (such as dimensions of the audience
areas, positions and capacity of the coupling points) you can use those data for a better design. At
this point, it is fundamental to make use of a series of software tools that permit experimentation with
computer simulations. The employment of simulation software and the installation designer's ability are
what it takes to define the performance of a vertical array quickly and precisely.

4.2.1 LAC

The LAC simulation software is a fundamental instrument in the design of an AXIOM array system.
The software allows an intuitive and simple simulation of a vertical array while taking every mechanical
constraint into account. The LAC was designed to be a useful tool for vertical array systems. It allows
operation on the vertical section of the area where the array will be arranged, rather than on a three-
dimensional space. This is not a limit as the design of the array coverage depends on the vertical axis
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only ; furthermore, the two-dimensional vision drastically reduces time spent working with the simulation
software. The simulation accuracy is guaranteed by the calculation algorithm which is based on real
high resolution measurements of each enclosure. Furthermore, because of its nature as a work tool, the
LAC takes into consideration only the direct sound coming from the array and disregards any possible
reflection coming from the environment.
The LAC software features two main windows, the Vertical View and the Mechanical View, that need
to be used in sequence when inserting all data referring to the venue where the AXIOM vertical array
system will be used.
At the start, the Vertical View window pops up automatically (figure 4.1), as the working procedure
requires the insertion of all data referring to the location (dimensions and structure) in a module called
Audience, then of all data about the array (model and number of speakers, relative angles between
speakers) in modules named Array Mounting and Array Configuration, finally the insertion of all simula-
tion parameters in the module named Simulate.
After completion of the above mentioned operations, in Mechanical View (figure 4.2) you can verify
the coupling position of the flying bar and, eventually, you can manually configure the suspension points
according to the load capacity allowed by the available suspension structure. There are two ways to
select the windows: clicking on definitions in the main menu or clicking directly in the area named
Cluster Preview. This allows rapidity while choosing the best configuration for the system.
The Miscellaneous module contains a series of information related to the general layout of the sys-
tem, to the overall centre of mass and to the total weight of the array you've created. While positioning
each speaker, the observation of where each single element points to may be of help in arranging them
so that the sound energy radiating from the whole array can be duly directed.
While configuring the array you can set the position of the suspension point, the angle of the flying
bar, the number of elements composing the array and each speaker's relative angle. The Autoconfig.
button allows the program to suggest a good starting point for the arrangement of each element's relative
angle. The result is not the best configuration possible, but only a good starting point. Manual changes
always need to be made to relative angles, but the suggested configuration is always composed of an
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This statement is not absolutely true, as the dispersion on the horizontal axis is not completely independent, but it is an
acceptable assumption when approximating and finding the best setting for the array.
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4. Sound design with AXIOM