Nexo GEO S8 - Manual (Page 18)

P.18 GEO APPLICATION GUIDELINES
GEO A PPLICATION G UIDELINES
GEO is a highly adaptable and flexible system due to the unique performance factors of the patent-pending
Hyperboloid Reflective Wavesource, the Configurable Directivity Device flanges and other innovations.
However, like all tools, your GEO system has been designed to function in specific ways: these lend
themselves to many situations, but not all. When designing and deploying GEO arrays, keep the following
considerations in mind.
Minimum Array Height (Vertical Tangent Arrays)
Like any “line array,” GEO’s ability to control lower frequencies with longer wavelengths is determined by the
height of the array. NEXO recommend that curved vertical GEO tangent arrays include at least four (4) S805’s
and one (1) S830. Lines shorter than this will not provide adequate control of lower frequencies. You will see
this in NS-1: the dBA trace will curve downward and will approach the red HF trace towards the rear of the
listening area. This indicates that lower frequencies are falling in level relative to the higher frequencies.
Optimum Height of the Bumper
Can be found by experimenting with different heights and aiming angles in NS-1. Your system can also be
ground staked by using the proper accessory.
How Loud for the Crowd?
Keep in mind that due to the superior coherency of GEO arrays, you may not need to get as loud in order to
“hear what is going on” as was the case with previous generations of sound reinforcement loudspeakers using
coercive megaphone-variant horn designs. The following chart offers some guidelines about the capability of
curved vertical GEO tangent arrays of various lengths. Maximum values in dBA are for all cabinets angled at
0.31°, minimum values are for all cabinets angled at 5° ; these values are calculated for open air conditions.
For an audience of the indicated total length, the ±3 dB value will probably fall somewhere in between the Min
and Max values. So a four-tall vertical tangent array, you will be able to produce levels of between 105 dBA
and 110 dBA from the front to the rear of a 10m long audience area, and from 87 to 92 dBA throughout an
80m long audience area.
GEO Array Total Length of Audience Area
Array Length Output ±3 dB 10 meters 20 meters 40 meters 80 meters
dBA Min 105 99 93 87 4 x S805
dBA Max 110 104 98 92
dBA Min 106 100 94 88 8 x S805
dBA Max 111 108 104 98
dBA Min 107 101 95 89 12 x S805
dBA Max 111 108 105 100
dBA Min 107 102 96 90 16 x S805
dBA Max 113 110 107 104