
Introduction
This guide provides instruction on what S.A.F.E. components are required, and how to connect them, to create
several example arrays. The suspension points, hardware, and methods that are used to hang the array must
meet professional rigging standards. JBL Technical Note Volume 1, Number 14 explains basic principles for
suspending loudspeaker systems and provides further references.
Safety
Factors and Load Ratings
S.A.F.E. hardware is designed, engineered, and certified with a 6:l safety ratio (i.e. if the array weighs 300 lbs the
support structure must be capable of at least 1800 lbs). Correct use of this hardware is required for secure array
construction. Model 4892 loudspeakers with truss module have been pull tested and rated at 5200 pounds break
strength, with a 6:I safety factor each 75 pound enclosure can support a working load of 866 pounds (a vertical
array of 10). The working load ratings of other components are: connecting bar - 1387; shackle mount - 496 Ibs;
stacking bracket 427 lbs; quick release pin - 1783 Ibs. As an example of how to use these numbers, we can
calculate how many 4892 enclosures can be suspended from one pair (two) shackle mounts. The working load
rating for each shackle mount is 496 lbs; each 4892 weighs 75 lbs with two truss modules; if each shackle mount
supports one half the array, the maximum number of enclosures that can be supported is: (2 x 496 Ibs) ii 75 lbs
= 13 Careful calculations should be performed to ensure that all components are used within their rated R-ork
load before the array is suspended. Remember: the weakest component determines the size and safety of the
entire arrav! CAUTION! Before suspending any array always inspect all components of the array (enclosure,
truss module, threaded fasteners, connecting hardware, and lifting hardware) for cracks, deformations, corrosion,
missing or damaged parts that could reduce strength and safety of the array. Use only load rated hardware.
Building structural supports and hoist motors.require inspection prior to each use by knowledgeable profession-
als Never exceed maximum recommended load ratings.
Components and Array Construction
The S.A.F.E. series of modular flying hardware eliminates the cost and bulk of large custom designed fly bars. Five
basic items- truss module, connecting bar, shackle mount, stacking bracket, and quick release pins- easily
combine to assemble a rigid array. Truss modules attach to the loudspeaker top and or bottom (we recommend
both) using its internal steel braces, the connecting bars then join the truss modules using quick release pins.
Lifting points for the array are created by attaching shackIe mounts to the truss modules with the release pins.
Straight vertical arrays are formed by connecting one top truss to a bottom truss using a stacking bracket, curved
vertical arrays are created using multiple shackle mounts as shown later. All assembly is made with quick release
pins for positive, easy connections. ALL QUICK RELEASE PINS MUST BE FULLY INSERTED FOR POSITIVE
LOCKING. Figure 1 shows a simple array of two 4892 loudspeakers with the S.A.F.E. hardware required to
connect them for “flying”. Note two connector bars are used top and bottom at rear of array. This is the pre-
ferred way to connect an array together.
QUICK RELEASE PIN \ , SHACKLE MOUNT
TRUSS MODULE
CONNECTING BAR ’ TRUSS MODULE
Figure 1