5
The PSW-6 is designed to be vertically arrayed in a
line and not in an arch. Creating a vertical line array, or
in other words, stacking PSW-6s in a column, narrows
the vertical coverage of the system while maintaining
its horizontal coverage. Adding more power to the sys-
tem simply involves adding additional cabinets to the
line array.
In this type of array, the vertical coverage will extend
less than 5° from the top of the column. This dictates
that the height of the vertical line array correspond
directly to the maximum height at which low frequency
coverage is required.
Creating a Quiet Area
When two PSW-6s are placed ten to thirty meters apart
at a 90° horizontal angle a quiet area develops behind
the speakers. In this area the SPL is at least 15 dB
below the level within the coverage area.
In the following MAPP
TM
(Multipurpose Acoustical Pre-
diction Program) predictions the lightest color repre-
sents the highest SPL.
Note that the fingers in the coverage pattern are
caused when a mono signal of equal amplitude is sent
to two spaced speakers. Amplitude or phase panning
will minimize the interference pattern and smooth the
polar response.
The advantages of creating a quiet zone around the
stage would include less system leakage into open
microphones, reduced interference between the house
and monitor systems, and reduced exposure to high
SPL for those within the quiet area.
2 PSW-6s at 20 meters splayed 90
o
with a mono singal of equal level.
