Nexo GEO M12 Series, System Manual

Page: 68 / 90

Page 68/90 SYSTEM CHECK ALIGNMENT GUIDELINES
Electronic calculator with trigonometric functions to calculate the height from ground level to points in the
room. The formula to calculate height of a point from measured angle and distance is:
Height of point = Sin (vertical angle in degrees) x distance to point
NB: Take care when using spreadsheets as they calculate using radians by default. To convert degrees
to radians, use the formula:
Angle (in radians) =3.142 x Angle (in degrees)/180
Computer – Laptop or Desktop PC running Windows 8 with the current version of NEXO NS-1 installed.
It is not possible to configure a GEO tangent array properly without using NS-1. Note that, when NS-1
designs are prepared prior to arrival at the venue, it is often necessary to modify or update the design to
accommodate special circumstances. A PC is absolutely essential to make such changes.
Audio Analysis Software – recommended but not absolutely essential, programs such as Systune TM ,
Smaart
TM
enable rapid and detailed analysis of the installation. Consider taking a training course in using
one of these tools if you are not already competent with them – it will pay dividends in increased
performance of the system.
7.5 GEO M12
– MSUB18 System Check List
It is essential to execute all these check steps prior to perform a sound check o
n the “front end” to the
system. Following this checklist step by step will prevent many troubles and will save time in the end.
Are the speakers properly connected and angled?
Attach the first series of modules to the bumper.
Before flying, verify that all channels of all modules are functioning properly.
To check that all elements have the proper amplitude and phase, you should listen to the upper boxes at
a close distance (<1 meter). You should be able to move from the top to the bottom of the cluster without
hearing any change in the tonal balance.
Verify that the angle settings are the same on both sides of each module.
Raise the bumper, attach the next series of modules and repeat the above checks.
Make sure that these series of modules sum properly with the modules above them.
When all the modules are flown, check that the aiming angles are the same left and right.
Make sure that multiple GEO M12 and MSUB18 are summing properly: 6 dB gain per doubling of quantity.
Final Pre-Sound Check Check
Play a CD track mono left, and then right: both sides must sound strictly identical. When listening in the
centre between Left and Right GEO M12s
, everything from LF to HF should be located to the “phantom
centre
” position. If not, repeat the above check sequence to identify the source of the problem.