x-array flying manual

7/30/2019 X-Array Flying Manual

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Flying Manual

and Structural Ratings

X-ARRAY CONCERT SYSTEMS


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X-Array Loudspeaker Systems

RIGGING-SAFETY WARNING

This document details general rigging practices appropriate to the sound industry, as they would applyto the rigging of Electro-Voice X-Array loudspeaker systems. It is intended to familiarize the readerwith standard rigging hardware and techniques for suspending X-Array loudspeaker systems over-head. Only persons with the knowledge of proper hardware and safe rigging techniques should attemptto suspend any sound systems overhead. Prior to suspending any Electro-Voice X-Array loudspeakersystems overhead, it is essential that the user be familiar with the strength ratings, rigging techniques

and special safety considerations outlined in this manual. The rigging techniques and practices recom-mended in this manual are, of necessity, in general terms to accommodate the many variations in loud-speaker arrays and rigging configurations. As such, the user is expressly responsible for the safety of allspecific X-Array loudspeaker-array designs and rigging configurations as implemented in practice.

All of the general rigging material contained in this manual is based on the best available engineeringinformation concerning materials and practices, as commonly recognized in the United States, and isbelieved to be accurate at the time of the original printing. As such, the information may not be directlyapplicable in other countries. Furthermore, the regulations and requirements governing rigging hardwareand practices may be superseded by local regulations. It is the responsibility of the user to ensure thatany Electro-Voice loudspeaker system is suspended overhead in accordance with all current federal,state and local regulations.

All specific material concerning the strength ratings, rigging techniques and safety considerations for theX-Array loudspeaker systems is based on the best available engineering information concerning theuse and limitations of the products. Electro-Voice continually engages in testing, research and develop-ment of its loudspeaker products. As a result, the specifications are subject to change without notice. Itis the responsibility of the user to ensure that any Electro-Voice loudspeaker system is suspended over-head in accordance with the strength ratings, rigging techniques and safety considerations given in thisdocument and any manual update notices. All non-Electro-Voice associated hardware items necessaryto rig a complete X-Array loudspeaker array (grids, chain hoists, building or tower supports and mis-cellaneous mechanical components) are the responsibility of others.

Electro-Voice

February, 1998


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TABLE OF CONTENTS

PAGES

RIGGING-SAFETY WARNING

0. INTRODUCTION

1. X-ARRAY RIGGING SYSTEM

1.1 Overview of the X-Array Flying Systems ............................................................................ 1-2

1.2 Loudspeaker Enclosure Details ............................................................................................. 2-5

1.3 Rigging Hinge Details ............................................................................................................ 5-7

1.4 Rigging Strap Details ............................................................................................................. 7-8

1.5 Grid Details ............................................................................................................................... 8

2. X-ARRAY FLYING TECHNIQUES

2.1 Enclosure and Horn Orientation .......................................................................................... 9-10

2.2 Adjusting the Vertical Angles ............................................................................................. 10-12

Using the Xrsl (long wire-rope rigging strap) Between Enclosures ........................................ 10

Using the Xrsl (at the Grid ................................................................................................. 10-11

Using the Xrss (short wire-rope rigging strap) Between Enclosures ................................. 11-12

Using the Xrss at the Grid ...................................................................................................... 11

Multiple Enclosure Angles ...................................................................................................... 12

2.3 Adjusting the Horizontal Angles ......................................................................................... 12-13

2.4 Balancing and Distributing the Load .................................................................................. 13-14

Array Load Distribution ...................................................................................................... 13-14

Balancing the Grid .................................................................................................................. 14

2.5 Using Pull-Up Lines ........................................................................................................... 14-15

Pull-Up Line Techniques ................................................................................................... 14-15

CAUTIONS for Pull-Up Lines ................................................................................................. 15

3. RIGGING-STRENGTH RATINGS, SAFETY .............................................................................. 15-23

FACTORS AND SPECIAL CONSIDERATIONS

3.1 Working-Load Limit and Safety Factors ...................................................................... 15-16

Definitions .................................................................................................................... 15-16

CAUTIONS for Working-Load Limits and Safety Factors ................................................. 16

3.2 Structural Rating Overview .......................................................................................... 16-17

3.3 Simplified Structural-Rating Guidelines ............................................................................ 17

The Guidelines ................................................................................................................. 17

CAUTIONS for the Simplified Structural-Rating Guidelines ........................................ 17-19

Discussion of Array Examples .......................................................................................... 19


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3.4 Complex Structural-Rating Analysis .................................................................................. 19-20

Rear Rigging Point Structural-Strength Rating .................................................................. 19-20

(Xrhg, Xrhp, Xrhl & NH32102-2)

Xrhg (grid hinge)

Xrhp (pick-up hinge)

Xrhl (linking hinge)

NH32102-2 (New Haven double-stud swivel-ring fitings)

Front Rigging Point Structural-Strength Rating ................................................................. 20-21(Xrss, Xrsl & NH32102-2)

Xrss (short wire-rope rigging strap)

Overall Enclosure Structural-Strength Rating ........................................................................ 21

CAUTIONS for a Complex Structural-Rating Analysis ........................................................... 21

3.5 Special Considerations ...................................................................................................... 21-23

Double-Stud Fittings .......................................................................................................... 21-23Flying a Single Enclosure ....................................................................................................... 23

3.6 Electro-Voice Structural Analysis Procedures ........................................................................ 23

4. RIGGING INSPECTION AND PRECAUTIONS .......................................................................... 23-24

5. REFERENCES ................................................................................................................................ 24

Rigging References

Mechanical Engineering References

Acoustical Engineering References

APPENDICES .................................................................................................................................. 24

A. SERVICING THE X-ARRAY RIGGING ................................................................................. 25

B. X-ARRAY RIGGING ACCESSORIES ................................................................................... 25


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0. INTRODUCTION

The X-Array product line represents importantadvancements in concert-sound-reinforcementtechnology. The design goals called for the high-est acoustic-output capability with the highestfidelity, in lightweight, compact enclosures that

were easy to array. The development began witha clean sheet of paper and took an integrated ap-proach. The individual loudspeaker drivers, horns,enclosures, rigging hardware and system configu-rations were designed from the ground up specifi-cally for this high-performance application. A briefdescription of the X-Array product line is in-cluded below. Consult the individual system engi-neering data sheets for detailed specifications.

Xf: Far-field, two-way, MB/HF loudspeaker sys-tem with a 40H x 20V coverage pattern. Thesystem has two ND12A 305-mm (12-in.) MBdrivers and two ND5-16 76-mm (3-in.) HF com-

pression drivers. The Xf utilizes the full-sizeX-Array enclosure shell and the standardX-Array flying hardware.

Xn: Near-field, three-way, LF/MB/HF loud-speaker system with a rotatable 60 x 40 cover-age pattern. The system has one EVX-180B457-mm (18-in.) woofer, one ND12A 305-mm(12-in.) MB driver and one ND5-16 76-mm (3-in.)HF compression driver. The Xn utilizes the full-size X-Array enclosure shell and the standardX-Array flying hardware.

Xb: Bass loudspeaker system with twoEVX-180B 457-mm (18-in.) woofers. The Xb

utilizes the full-size X-Array enclosure shelland the standard X-Array flying hardware.

Xds: Subwoofer loudspeaker system with twoEVX-180B 457-mm (18-in.) woofers. The Xdsutilizes the double-wide X-Array enclosureshell and does not have flying hardware.

Xcn: Compact near-field, two-way, MB/HF loud-speaker system with a rotatable 60 x 40 cover-age pattern. The system has one ND12A 305-mm(12-in.) MB driver and one ND5-16 76-mm (3-in.)HF compression driver. The Xcn utilizes the half-size X-Array enclosure shell and the standard

X-Array flying hardware.Xcb: Compact bass loudspeaker system withone 457-mm (18-in.) EVX-180B woofer. The Xcbutilizes the half-size X-Array enclosure shelland the standard X-Array flying hardware.

Numerous accessories are available to completean X-Array loudspeaker system, including rig-ging hardware, digital electronic controllers,power amplifiers, cables, racks, cases, dollyboards and speaker covers. See AppendixB. X-Array Rigging Accessoriesfor a list ofavailable accessories and where to purchase

them. See Appendix A. Servicing the X-ArrayRiggingfor service information.

1. X-ARRAY RIGGING SYSTEM

1.1 Overview of the X-Array Flying System

The X-Array rear-hinge/front-strap flying systemmakes constructing arrays easy, predictable andrepeatable. The hinging concept, combined with

the trapezoidal enclosures, allows arrays to beconstructed with the least possible spacing be-tween enclosures.

A basic two-enclosure flying system is shown inFigure 1 that illustrates the integral componentsthat make up a typical X-Array flying system.All of the flying X-Array loudspeaker systemsutilize horizontal rigging-track hardware on theback of the enclosure (at both the top and bottom)and vertical rigging-track hardware on the frontof the enclosures (at both the left and right sides).The rear rigging-hinge hardware provides the

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primary support for the loudspeaker enclosures,while the front rigging hardware is mainly for aim-ing the enclosures vertically. (The front does pro-vide some secondary support, however.)

Figure 1a illustrates an array column suspendedwith a grid. Like the loudspeaker systems, the grid

utilizes horizontal rigging-track hardware at theback and vertical rigging-track hardware at thefront. The top enclosure is secured to the gridwith two quick-release Xrhg grid hinges at therear, and two quick-release Xrss short wire-roperigging straps at the front. The grid hinge has onlyone possible vertical attachment position on boththe enclosure and the grid. The front straps, how-ever, have six possible vertical attachment posi-tions to choose from on the enclosure and twopossible vertical attachment positions to choosefrom on the grid. The grid hinges allow the enclo-sure to pivot from its top back corner. The verticalangle of the top enclosure, relative to the grid, isset by the linear position of the front rigging strapsin the track on the front of the enclosure and onthe grid.

The bottom enclosure shown in Figure 1a is linkedto the top enclosure with two quick-release Xrhllinking hinges at the rear and two quick-releaseXrsl long wire-rope rigging straps at the front. Thelinking hinges allow the bottom enclosure to pivotfrom the back corner of the top enclosure. Thevertical angle of the bottom enclosure, relative tothe top enclosure, is set by the linear position ofthe front rigging straps in the track on the front ofthe top and bottom enclosures. Additional enclo-sures may be linked together in the same fashion,as long as the working-load limits for any of theenclosures, rigging hinges or straps are not ex-ceeded. The array column is raised into positionby a motorized chain hoist of sufficient load rating.

Figure 1a shows the short Xrss rigging strapssecuring the top enclosure to the grid and thelong Xrsl rigging straps linking the two enclosuresbecause this is the most common configuration;however, the straps may be interchanged inmany circumstances. When the short Xrss riggingstraps are used between the top enclosure andthe grid, the enclosure may be angled upwardrelative to the grid or downward a moderateamount. When the long Xrsl rigging straps areused between the top enclosure and the grid, theenclosure may be hung parallel to the grid, orangled downward substantially relative to the grid.When the long Xrsl straps are used between en-closures, the bottom enclosure may be hungparallel to the top enclosure or angled downwardsubstantially relative to the top enclosure. Whenthe short Xrss straps are used between enclo-sures, the bottom enclosure may be hung parallel

to the top enclosure or angled downward a mod-erate amount relative to the top enclosure.

When a grid is used, each array column mustbe balanced by adjusting the position of the gridhanger towards the front or back until the gridhangs level. Several of the grids may be con-

nected together horizontally and raised in unison.When using the grid, the splay angle betweenarray columns is adjusted by the positioning of thegrid retractable-coupler arms.

In permanent installations, the motorized chainhoists and grids are sometimes eliminated, andthe loudspeaker columns can be secured directlyto the building structure. This application is shownin Figure 1b. The back of the top enclosure is sus-pended with two Xrhp pickup hinges. Each Xrhppickup hinge utilizes standard chain that will ac-cept chain connectors, shackles or other standardrigging hardware which are, in turn, secured to

the building structure via custom wire-rope orchain assemblies. The front of the enclosure issuspended by two New Haven NH32102-2double-stud swivel-ring fittings attached to thefront track of the enclosure and which are, in turn,secured to the building structure via two customwire-rope or chain rigging assemblies. The hard-ware and techniques used to secure and anglethe bottom enclosure to the top enclosure areidentical to the previously described case wherea grid was employed.

In installations where a custom grid is employedthat does not use track that is compatible with the

X-Array Xrhg grid hinge or the Xrss or Xrsl rig-ging straps, the Xrhp pickup hinge and customwire-rope rigging straps that utilize New HavenNH32102-2 double-stud swivel-ring fittings canbe used to suspend the top enclosure as illus-trated inFigure 1b.

Note that the weight of an array can be quite sub-stantial and the grid, chain hoists and buildingstructural supports used to suspend the arraymust be capable of supporting such a load witha sufficient safety factor. The reader is directed tosection 5. Referencesof this manual for a list ofrigging references (for background in general rig-

ging practice) and mechanical engineering refer-ences (for background in structural engineeringanalysis).

1.2 Enclosure Rigging Hardware Details

All of the flying X-Array models utilize identicalrigging hardware, and they all have the samestrength ratings. Figure 2 shows key dimensions,weights and the centers of gravity for all of theX-Array systems.

A proprietary high-strength aluminum-alloy trackis used at the back of the enclosures near the top

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FIGURE 2a - Xf SYSTEM

TYP9.0

584.2 mm(23.00 in.)

353.8 mm(13.93 in.)

733.2 mm(28.87 in.)

758.8 mm(29.88 in.)CL

914.4 mm(36.00 in.)

457.2 mm(18.00 in.)

384.1 mm(15.12 in.)

WEIGHT: WITHOUT EXTERNAL RIGGING: 87.1 kg (192 lb)WITH EXTERNAL RIGGING: 90.2 kg (199 lb)

O

FIGURE 2d - X

914.4 mm(36.00 in.)

WEIGHT:

CL

736.6 mm(28.98 in.)

758.8(29.8

1166 mm(45.92 in.)

667.2 mm(26.27 in.)

18TYP.

FIGURE 2b - Xn

TYP9.0

584.2 mm(23.00 in.)

353.8 mm(13.93 in.)

733.2 mm(28.87 in.)

758.8 mm(29.88 in.)

914.4 mm(36.00 in.)

409(16.

CL

WEIGHT: WW

O

FIGURE 2c - Xb SYSTEM

TYP9.0

584.2 mm(23.00 in.)

353.8 mm(13.93 in.)

733.2 mm(28.87 in.)

758.8 mm(29.88 in.)CL

914.4 mm(36.00 in.)

457.2 mm(18.00 in.)

438.5 mm(17.26 in.)

WEIGHT: WITHOUT EXTERNAL RIGGING: 83.5 kg (184 lb)WITH EXTERNAL RIGGING: 86.6 kg (191 lb)

O

FIGURE 2 - X-ARRAY LOUDSPEAKER SYSTEMS

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WEIGHT:WEIGHT: 87.1 kg (192 lb)

WEIGHT: 83.5 kg (184 lb)


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and bottom for the attachment of two Xrhg, Xrhlor Xrhp rigging hinges. The track/bracket assem-bly is extruded as a single piece. One assemblyties into the back and top of the enclosure, whilea second assembly ties into the back and bottomof the enclosure. High-strength, aluminum-alloybars inside the enclosure tie the top and bottomtrack/bracket assemblies together, minimizingthe load applied to the enclosure shell. The trackdimensions are similar to the widely used heavy-duty aircraft L-track (such as the New HavenNH34030-3HD or ATM Fly-Ware ATM-TRACK).The cutouts in the rear rigging track are shown inFigure 3a. The large cutout in the center of thetrack is for inserting the rigging hinges. The smallholes in the base of the track are for locking therigging hinges. The round cutouts on either sideare provided so that two New Haven NH32102-2double-stud swivel-ring fittings may be installedfor light-duty lifting applications and for pull-ups.

Key dimensions for the rear rigging hardware arepresented in Figure 3a. (See section 3. Rigging-Strength Ratings, Safety Factors and SpecialConsiderationsfor a detailed discussion of thestructural strength of the enclosure rear riggingpoints.)

At the front of the enclosure is another pair ofproprietary high-strength, aluminum-alloy track/bracket assemblies which are also extruded as asingle piece. One assembly ties into the left side,top, bottom of the enclosure, while a second as-sembly ties into the right side, top and bottom ofthe enclosure. The front track extends from the

top to the bottom on both sides of the enclosure,eliminating the load applied to the enclosure shell.These track dimensions are also similar to thewidely used heavy-duty aircraft L-track (NewHaven NH34030-3HD or ATM Fly-Ware ATM-TRACK). On both sides of the enclosure, the frontrigging track has six cutouts near the top andbottom, as shown in Figure 3b. The New HavenNH32102-2 double-stud swivel-ring fittings onthe Xrss and Xrsl wire-rope rigging straps may beinstalled at any of the cutouts. The relative anglebetween a pair of enclosures (or the top enclo-sure and the grid) is set by the position of the

front rigging-strap fittings in the track cutouts.Key dimensions for the front rigging hardwareare presented in Figure 3b. (See section 3. Rig-ging-Strength Ratings, Safety Factors and SpecialConsiderationsfor a detailed discussion of thestructural strength of the enclosure front riggingpoints.)

To facilitate the installation and removal of thelinking hinges, alignment feet are installed on thetop and bottom of the X-Array enclosures. Malefeet (protruding feet) are located on the bottomof the enclosures, while female feet (concave

FIGURE2e-

XcnSYSTEMF

IGURE2(contd)-

X-A

RRAYLOUDSPEAKER

SYSTEMS

FIGURE2f-

XcbSYSTEM

595.9mm

(23.4

6in.)

(23.0

0in.)

584.2mm

758.8mm

(29.8

8in.)

353.8mm

(13.9

3in.)

733.2mm

(28.8

7in.)

9.0

TYP

CL

WEIGHT:60.8

kg(134lb)

292.1mm

(11.5

0in.)

391.2mm

(15.4

0in.)

595.9mm

(23.4

6in.)

433.6mm

(17.0

7in.)

301.6mm

(11.8

8in.)

WEIGHT:55.8

kg(123lb)

758.8mm

(29.8

8in.)

CL

9.0

TYP

733.2mm

(28.8

7in.)

584.2mm

(23.0

0in.)

353.8mm

(13.9

3in.)

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dishes) are located on the top. When one enclo-sure is stacked or lowered on top of another, themale feet on the bottom of the upper enclosureslide into the female feet on the top of the lowerenclosure, automatically aligning the enclosures.If the enclosures do not self align, a light side-ways push is all that is needed to make the feet

engage and align. These features allow fastassembly and disassembly of large loudspeakerarrays in touring applications.

1.3 Rigging Hinge Details

Xrhg Grid Hinge: Two Xrhg grid hinges are usedto attach the back of an X-Array enclosure tothe back of an X-Array-compatible grid. (Seesection 1.5 Grid Detailsfor a discussion of thegrid.) Each grid hinge consists of two precision-machined steel bases connected by an alloy-steelchain, as shown in Figure 4a. Each grid-hingebase has a locking pin which locks the hinge inplace horizontally in the track on the grid or

X-Array enclosure. (See section 3. Rigging-Strength Ratings, Safety Factors and SpecialConsiderationsfor a detailed discussion of thestructural strength of the grid hinges.)

The Xrhg grid rigging hinges need not be installedin the top enclosure and the grid simultaneously.The length of chain allows the grid hinges to beinstalled in the grid first. The grid can then befloated above the top enclosure while the otherends of the grid hinges are installed in the trackat the rear of the enclosures. The grid hingesmust be used in pairs and must be installed with

the chain near the ends of the track, as shown inFigure 5a. (Note: If one grid hinge is installed in-correctly with the chain at the center of the track,the second grid hinge will not fit into the track cut-out.) Key dimensions for the Xrhg grid hinges andthe enclosure are presented in Figures 4aand 5a.

To install an Xrhg grid hinge into the track of anenclosure, grasp one of the hinge bases and

firmly insert the hinge base into the long centercutout in the track, pressing in until the spring-loaded locking pin is fully retracted. Then applypressure to slide the hinge base sideways to-wards the end of the track until the spring-loadedlocking pin drops into the hinge-locking-pin hole inthe base of the track. Once the locking pin is fullyengaged, the grid hinge base will be immovable

in the track. ALWAYS CHECK TO MAKE SURETHE GRID-HINGE BASES ARE SECURELYLOCKED INTO THE TRACK, AND THAT THELOCKING PINS ARE FULLY ENGAGED IN THETRACK BEFORE LIFTING ANY LOUDSPEAKERENCLOSURES OVERHEAD. Use the same tech-nique for installing the other end of the Xrhg gridhinge in the track at the rear of the grid.

To remove the Xrhg grid hinge, grasp the locking-pin knob and pull out while applying pressure onthe hinge to slide the hinge base toward the longcutout at the center of the track. The hinge base

FIGURE 3a - ENCLOSUREREAR RIGGING TRACK

HOLE FOR RIGGINGHINGE LOCKING PIN

CUTOUT FOR LOCKINGDOUBLE-STUD FITTING

FIGURE 3 - ENCLOSURE RIGGING HARDWARE DETAIL

FIGURE 3b - ENCLOSURE FRONT RIGGING TRACK

79.0 mm(3.11 in.)

TYP.

25.4 mm(1.00 in.) TYP.

CUTOUT FOR INSERTINGRIGGING HINGES ANDDOUBLE-STUD FITTINGS

48.0 mm(1.89 in.)

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will come out of the track once it is aligned withthe center cutout. For added safety, the lockingpin has a special shape which engages with thetrack to prevent it from vibrating out of the trackhole during use. If the locking-pin knob seemsdifficult to pull out when removing the hinge,wiggle the hinge base while pulling out on theknob. When the hinge locking pin is centeredin the track hole, the pin will easily release.

Xrhl Linking Hinge: Two Xrhl linking hingesare used to link a pair of X-Array enclosurestogether at their adjacent back corners. Eachlinking hinge consists of two precision-machinedsteel bases connected by a heavy-duty steelhinge, as shown in Figure 4b. The hinge armspivot, allowing the enclosures to pivot at their

back corners. Each linking-hinge base has a lock-ing pin which locks the hinge in place horizontallyin the rear track of the enclosure. (See section 3.Rigging-Strength Ratings, Safety Factors andSpecial Considerationsfor a detailed discussionof the structural strength of the linking hinges.)

An Xrhl linking hinge must be installed in the topand bottom enclosures simultaneously. The link-ing hinges must also be used in pairs and in-stalled with the hinge arms near the ends of therigging track as shown in Figure 5b. (Note: If onelinking hinge is installed incorrectly with the hinge

arms at the center of the track, the second linkinghinge will not fit into the track cutout.) Key dimen-sions for the Xrhl rigging hinges and the enclo-sure are presented in Figures 4b and 5b.

To install an Xrhl into the track of a pair of enclo-sures stacked one on top of the other, grasp both

of the hinge bases and firmly insert both of thehinge bases simultaneously into the long centercutouts in the track of both enclosures, pressingin until both spring-loaded locking pins are fullyretracted. Then apply pressure to slide the hingebases sideways towards the end of the track untilboth spring-loaded locking pins drop into thehinge-locking-pin holes in the base of the trackon both enclosures. Once the locking pins arefully engaged, the linking hinge bases will beimmovable in the track. ALWAYS CHECK TOMAKE SURE THE LINKING-HINGE BASES ARESECURELY LOCKED INTO THE TRACK, ANDTHAT THE LOCKING PINS ARE FULLY EN-GAGED IN THE TRACK BEFORE LIFTING ANYLOUDSPEAKER ENCLOSURES OVERHEAD.

To remove the Xrhl linking hinge, grasp both ofthe locking-pin knobs and pull out while applyingpressure on the hinge to slide the hinge basetoward the long cutout at the center of the track.The hinge base will come out of the track onceit is aligned with the center cutout. Like the gridhinge, the locking pin has a special shape whichengages with the track to prevent it from vibratingout of the track hole during use. If the locking-pinknob seems difficult to pull out when removing thehinge, wiggle the hinge base while pulling out onthe knob. When the hinge locking pin is centeredin the track hole, the pin will easily release.

Xrhp Pickup Hinge: Two Xrhp pickup hingesare used to attach to the back of the topX-Array enclosure in a column to lift the arraywhere no grid is used or where a custom grid thatis not X-Array compatible is used. Each pickuphinge consists of a single precision-machinedsteel base connected by an alloy-steel chain, asshown in Figure 4c. The pickup-hinge base has alocking pin which locks it in place when insertedinto the rear track of an X-Array enclosure.Standard chain-link couplers or connectors canbe used to attach the 7.95-mm (5/16-in.) alloy-steel chain of the Xrhp to standard rigging hard-ware (such as shackles, other chains, wire-ropeslings, etc.), which are in turn secured to a cus-tom grid or directly to the building structure. (Seesection 3. Rigging-Strength Ratings, Safet Fac-tors and Special Considerationsfor a detaileddiscussion of the structural strength of the pickuphinges.)

The pickup hinges must be used in pairs and in-stalled with the chain near the ends of the track,

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as shown in Figure 5c. (Note: If one pickup hingeis installed incorrectly with the chain at the centerof the track, the second pickup hinge will not fitinto the track cutout.) Key dimensions for the Xrhprigging hinges and the enclosure are presented inFigures 4cand5c.

To install an Xrhp pickup hinge into the track ofan enclosure, grasp the hinge base and firmly in-sert it into the long center cutout in the track,pressing in until the spring-loaded locking pin isfully retracted. Then apply pressure to slide thehinge base sideways towards the end of the trackuntil the spring-loaded locking pin drops into thehinge-locking-pin hole in the base of the track.Once the locking pin is fully engaged, the pickuphinge base will be immovable in the track. AL-WAYS CHECK TO MAKE SURE THE PICKUP-HINGE BASES ARE SECURELY LOCKED INTOTHE TRACK, AND THAT THE LOCKING PINS

ARE FULLY ENGAGED IN THE TRACK BE-FORE LIFTING ANY LOUDSPEAKER EN-CLOSURES OVERHEAD.

To remove the Xrhp pickup hinge, grasp the lock-ing-pin knob and pull out while applying pressureon the hinge to slide the hinge base toward thelong cutout at the center of the track. The hingebase will come out of the track once it is alignedwith the center cutout. For added safety, the lock-ing pin has a special shape which engages withthe track to prevent it from vibrating out of thetrack hole during use. If the locking-pin knobseems difficult to pull out when removing the

hinge, wiggle the hinge base while pulling out onthe knob. When the hinge locking pin is centeredin the track hole, the pin will easily release.

1.4 Rigging Strap Details

Two rigging straps (either two Xrss straps or twoXrsl straps) are used to attach a pair of enclo-sures together at the front, or to attach the front ofthe top enclosure to an X-Array-compatiblegrid. The short Xrss wire-rope rigging strap,shown in Figure 6a, and the long Xrsl wire-roperigging strap, shown in Figure 6b, are identicalexcept for their length. Both consist of two NewHaven NH32102-2 double-stud swivel-ring fittings

connected together with a 4.76-mm (.188-in.) di-ameter, galvanized and black-plastic-coated, air-craft wire rope. (See section 3. Rigging-StrengthRatings, Safety Factors and Special Consider-ationsfor a detailed discussion of the structuralstrength of the rigging straps.)

Two Xrss straps are typically used to attach thefront of the top enclosure to an X-Array-compat-ible grid as shown in Figure 7a; however, the Xrslmay be substituted. Key dimensions for the frontrigging straps on the enclosures are presented inFigure 7a. (See section 1.5 Grid Detailsfor a dis-

cussion of the grid.) When the short Xrss riggingstraps are used between the top enclosure andthe grid, the top enclosure may be angled upwardrelative to the grid or downward a moderateamount. When the long Xrsl rigging straps areused between the top enclosure and the grid, theenclosure may be hung parallel to the grid, orangled downward substantially relative to the grid.

Two Xrsl straps are typically used to link two en-closures together at the front; however, the Xrssmay be substituted. When the long Xrsl straps areused between enclosures, the bottom enclosuremay hung parallel to the top enclosure or angleddownward substantially relative to the top enclo-sure. When the short Xrss straps are used be-tween enclosures, the bottom enclosure mayhung parallel to the top enclosure or angleddownward a moderate amount relative to the topenclosure. (See the section 2.2 Aiming the Enclo-suresfor details.)

To attach the front of an X-Array enclosure to abuilding structure, custom wire-rope assemblies

may be fabricated using the New HavenNH32102-2 double-stud swivel-ring fitting. Thatsame fitting may be used on custom wire-ropeassemblies to secure the front of an enclosure toa custom grid that does not have track at thefront.

In certain circumstances, two New HavenNH32102-2 double-stud swivel-ring fittings may

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be used on custom wire-rope assemblies toattach to the rigging track on the back of anX-Array enclosure as shown in Figure 7b. Keydimensions for the rigging straps on the enclo-sures are presented in Figure 7b. In light liftingapplications, double-stud-fitting custom assem-blies could be used instead of the Xrhp pickuphinges. The reader is cautioned that THE STAN-DARD DOUBLE-STUD FITTINGS ARE NOT ASSTRONG AS THE Xrhp, Xrhg and Xrhl RIGGINGHINGES. (See section 3. Rigging Strength-Rat-ings, Safety Factors and Special Considerationsfor a detailed discussion of the structural strength

of the NH32102-2 fittings and the rigging hinges.)To attach the double-stud swivel-ring fittings tothe enclosure rigging track, as shown in Figure 7,grasp the fitting between the thumb and first twofingers. Push in the spring-loaded safety lockingpin with your free hand and lift the outer lockingring over the pin by pressing with your thumb.Continue to press with your thumb until the twolegs of the fitting are fully exposed. Insert the tworound feet on the end of the legs into the roundcutouts in the track and slide the fitting to thedesired position. Center the main body of the fit-ting over one of the track cutouts, with the feet

located on either side (i.e., the feet positioned di-rectly under the teeth of the track). Release theouter locking ring. The round protrusion on thebottom of the fitting should lock into the round cut-out in the track, with the locking ring retracting toits normal position, allowing the safety pin to reap-pear and extend over the locking ring. If the fittingdoes not lock into the track, nudge it along thetrack and wiggle as necessary until it settles intoposition. If the outer locking ring does not fully re-tract, push the ring towards the track until thesafety pin reappears and extends over the locking

ring. When locked, the fitting will be immoveablein the track and the locking ring of the fitting maynot be lifted. To remove the fitting, reverse theprocedure. ALWAYS CHECK TO MAKE SURETHAT THE DOUBLE-STUD FITTING IS SE-CURELY LOCKED INTO THE TRACK, ANDTHAT THE SAFETY PIN IS EXTENDED OVERTHE LOCKING RING BEFORE LIFTING ANYLOUDSPEAKER ENCLOSURE OVERHEAD.

1.5 Grid Details

ATM Fly-WareTM manufactures the MEGS-4000-Tgrid, shown in Figure 8, specifically for theX-Array loudspeaker systems. The grid is com-pletely compatible with the X-Array systems,and has track on the front and rear for connectingto the top enclosure in an array column. The trackon the rear of the grid, shown in Figure 8b, has asingle large cutout for inserting the Xrhg gridhinges, and has hinge locking-pin holes similar to

the track on the rear of the enclosures. Standarddouble-stud aircraft fittings cannot be used at therear of the grid. The track on the front of the grid,shown in Figure 8c, provides two attachment posi-tions for the Xrsl or Xrss rigging straps. A gridsuspending a column of loudspeakers is bal-anced, front to back, by adjusting the position ofthe hanger shown in Figure 8d. The hanger is se-cured to the center bar with bolts or quick-releasepins. Multiple positions for the hanger are avail-able from the back to the front of the grid.

Multiple grids can be linked together with retract-able couplers, shown in Figure 8e, the position of

which sets the splay angle between adjacent col-umns. Each grid comes with two long couplers inthe front and two short couplers in the rear. Thecouplers on one side of the grid have male endswhile the couplers on the other side of the gridhave female ends. This allows several grids to belinked together by inserting the male ends of onegrids couplers into the female ends of anothergrids couplers, as shown in Figure 8f. The cou-plers are secured to the front and rear grid barswith bolts or quick-release pins. The front andrear couplers may be swapped from front to rearto attain a wider range of splay angles. Two ex-amples are shown in Figures 8gand 8h.

The working-load structural-strength ratings of theX-Array loudspeaker systems allow a maximumweight of 726 kg (1,600 lb) to be suspended in asingle column, which is well within the working-load limit of the ATM Fly-Ware MEGS-4000-Tgrid. When using the MEGS-4000-T grid, alwaysfollow the manufacturers instructions, recommen-dations and safety precautions, and never exceedany structural limit as provided by ATM.

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2. X-ARRAY FLYING TECHNIQUES

The X-Array rear-hinge/front-strap flying systemmakes constructing vertical arrays easy, predict-able and repeatable. The enclosures utilize rig-ging hinges that allow them to pivot at their rearcorners. The relative vertical angles, from one en-

closure to another, are set by the position of thefront rigging straps. Horizontal angles are set atthe top of array columns by retractable couplingarms on the grids.

2.1 Enclosure and Horn Orientation

The X-Array systems lend themselves to easyarray construction. All of the full-size X-Arraymodels the Xf, Xn, and Xb have identical di-mensions and rigging. With grilles in place thefull-size systems are indistinguishable from oneanother, allowing them to be arrayed in any con-figuration while maintaining a consistent appear-

ance. The Xf and the Xb are acoustically sym-metrical side to side and top to bottom and, there-fore, do not need to be rotated upside down forany reason when designing arrays. The Xn, how-ever, is not acoustically symmetrical top to bottom(the low-frequency section is at one end, while the

mid-bass-/high-frequency section is at the otherend), which may necessitate that some enclo-sures be turned upside down for optimal arrayperformance. The Xn is shipped from the factorywith the woofer at the bottom and the mid-bass-/high-frequency section at the top. If the enclosureis turned upside down so that the woofer is upand the mid-bass-/high-frequency section isdown, the alignment feet on the enclosure mustbe swapped around so that the male feet (pro-truding feet) are on the bottom and the femalefeet (concave dishes) are on the top as arrayed.The grille should also be rotated so that the grille

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FIGURE 8 - ATM FLYWARE MEGS 4000-T X-ARRAY-COMPATIBLE GRID


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badge is right side up, maintaining a consistentappearance. In addition the high-frequency hornmay be rotated, offering the choice of a 60H x40V pattern or a 40H x 60V pattern.

All of the half-size X-Array models the Xcn,and Xcb also have identical dimensions and ap-

pearance with grilles on, and have rigging that isidentical to the full-size models. The Xcb is acous-tically symmetrical side to side and top to bottomand, therefore, does not need to be rotated up-side down for any reason when designing arrays.The Xcn, however, is not acoustically symmetricaltop to bottom (the high-frequency horn is offsetslightly to one end inside the mid-bass horn),which may necessitate that some enclosures beturned upside down for optimal array perfor-mance. The Xcn is shipped from the factory withthe high-frequency horn offset towards the bot-tom. If the enclosure is turned upside down sothat the high-frequency horn is at the top, thealignment feet on the enclosure must be swappedaround so that the male feet (protruding feet) areon the bottom and the female feet (concavedishes) are on the top as arrayed. The grilleshould also be rotated so that the grille badge isright side up, maintaining a consistent appear-ance. In addition the high-frequency horn may berotated, offering the choice of a 60H x 40V pat-

tern or a 40H x 60V pattern.

2.2 Adjusting the Vertical Angles

Using the Xrsl (long wire-ropr rigging strap)Between Enclosures: The long Xrsl riggingstraps are the primary recommendation for settingthe angle between enclosures because they pro-

vide the widest range between a pair of enclo-sures. Figure 9a shows the round cutouts (orholes) in the front rigging tracks of a pair of en-closures, each numbered 0 through 5. Thesetwelve positions allow a range of angles betweenenclosures from 0 (enclosures parallel to eachother) to 18down in 1.8 increments. For in-stance, when the fittings of the Xrsl rigging strapsare inserted into cutouts #0 on both the upperand lower enclosures (position 0-0), as shown inFigure 9b, the resulting angle between the two en-closures is 0. Notice in Figure 9b that the riggingstrap and fittings cover up all of the track cutouts

so that there are no round cutouts (or holes)showing. Thus, the 0-0 position can also bethought of as the 0-holes-showing position. Anequation can be written that predicts the relativeangle of the enclosures when the Xrsl is used:

Angle = - (Holes Showing) x 1.8 for the Xrsl

where negative (-) angles indicate down-ward angles and positive (+) angles indicateupward angles.

If the double-stud fittings of the Xrsl strap are in-

serted into cutout #3 in the upper enclosure andcutout #4 in the lower enclosure (position 3-4),as shown in Figure 9c, a total of 7 holes are show-ing, making the angle between the two enclosures-(7 x 1.8) = -12.6. This system makes it easy toobtain the desired vertical array shape withouthaving to experiment with balancing the enclo-sures.

Using the Xrsl (long wire-rope rigging strap) atthe Grid: The long Xrsl rigging straps may alsobe used to attach the top enclosure in an arraycolumn to the ATM Fly-WareTM MEGS-4000-Tgrid. The Xrsl rigging straps allow the top enclo-

sure to hang at 0 (parallel to the grid) to 10.8down relative to the grid in 1.8 increments.Figure 10a shows the two cutouts in the track onthe front of the ATM grid, numbered 0 and 1, andthe six cutouts in the enclosure track, numbered0 through 5. The same equation discussed in theprevious paragraph for determining angles be-tween enclosures also applies to the Xrsl whendetermining angles between the top enclosureand the ATM grid:

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Angle = - (Holes Showing) x 1.8 for the Xrsl

where negative (-) angles indicate down-ward angles and positive (+) angles indicateupward angles.

For example, when the fittings of the Xrsl strapsare inserted into cutout #0 on the grid and cutout#0 on the top enclosure (position 0-0), as shownin Figure 10b, no holes are showing and the angleof the top enclosure relative to the grid is-(0 x 1.8) = 0. If cutout #0 on the grid and #3 onthe enclosure are chosen (position 1-3), asshown in Figure 10c, a total of 3 holes are show-ing, making the angle of the top enclosure relativeto the grid -(3 x 1.8) = -5.4.

Using the Xrss (short wire-rope rigging strap)Between Enclosures: The short Xrss riggingstraps may also be used between enclosures;however, the Xrss offers a lesser range of down-ward angles than the long Xrsl rigging strap. Theshort Xrss rigging straps allow a range of anglesbetween the enclosures of 0 (enclosures are par-allel) to 10.8 down in 1.8 increments. The Xrssrigging strap is 101.6 mm (4.0 in.) shorter thanthe Xrsl strap. Therefore, for the same angle,there will be four more holes showing when theshort Xrss rigging strap is used compared to thelong Xrsl strap. This results in an additional 7.2upward angle when the short Xrss is used. Thus,the equation for the Xrss becomes:

Angle = 7.2- (Holes Showing) x 1.8for the Xrss

where negative (-) angles indicate downwardangles and positive (+) angles indicate upwardangles.

For example, if the fittings of the short Xrss strapsare inserted into track cutout #2 on both the upperand lower enclosures (position 2-2), as shown inFigure 11b, the resulting angle between the enclo-sures is 7.2 - (4 x 1.8) = 0 with a total of4 holes showing. If the fittings of the Xrss shortstraps are inserted into track cutout #4 on boththe upper and lower enclosures (position 4-4),as shown in Figure 11c, the resulting angle be-tween the two enclosures with 8 holes showingis 7.2- (8 x 1.8) = -7.2.

Using the Xrss at the Grid: The short Xrss

rigging straps are the primarily recommendationfor use with the ATM grid because they offer theability to angle the top enclosure both upwardand downward relative to the grid. The short Xrssrigging straps allow the top enclosure a range ofangles relative to the grid from 7.2 up to 3.6down in 1.8 increments. The same equation dis-cussed in the previous paragraph for determining

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angles between enclosures also applies to theXrss when determining angles between the topenclosure and the ATM grid:

Angle = 7.2- (Holes Showing) x 1.8for the Xrss

where negative (-) angles indicate down-

ward angles and positive (+) angles indicateupward angles.

For example, when the short Xrss straps are usedbetween the ATM grid and the top enclosure for0 relative angle between the two (position 0-4),there are 4 holes showing as illustrated inFigure 12b. This means that the formula for theshort Xrss strap must be offset by 4 compared tothe long Xrsl strap; or in this example, 7.2 -(4 x 1.8) = 0. If the fittings on the Xrss shortstraps are inserted into track cutout #1 on the grid

and track cutout #0 on the top enclosure (position1-0), as shown in Figure 12c, one hole is show-ing and the top enclosure is angled 7.2 -(1 x 1.8) = +5.4 upward relative to the grid.

Multiple Enclosure Angles: The relative verticalangle between the grid and the top enclosure orbetween adjacent enclosures is determined bythe attachment position of the Xrss and Xrsl rig-ging straps in the rigging track in the grid and en-closures. Note that the straps set the relativeanglesbetween grid and enclosures, and thatthose relative angles are cumulativewhen deter-mining the absolute angleof the enclosures lower

in the array. This is best illustrated by the ex-ample shown in Figure 13.

An Xrss rigging strap is attached at position 1-5between the ATM grid and the top enclosure,resulting in a relative angle between the grid andenclosure of -3.6. (See the sections immediately

above for how to calculate the relative anglesbased on the rigging strap attachment locations.)Since the grid is level at 0, the absolute angle oftop enclosure is -3.6 (pointing down). Movingdown the array, an Xrsl rigging strap is attachedin position 1-2 between the first and second en-closures, resulting in a relative angle of -5.4 be-tween the two. In other words, the secondenclosure is angled down 5.4 more than the topenclosure, making the absolute angle of the sec-ond enclosure -3.6 -5.4 = -9.0. Finally, an Xrslrigging strap is attached at position 2-2 betweenthe second and third enclosure, resulting in arelative angle of -7.2 between the two. In otherwords, the third enclosure is angled down 7.2more than the second enclosure, making the ab-solute angle of the third enclosure -3.6 -5.4-7.2= -16.2. Thus, the absolute vertical angle of anyenclosure in an array, is the sum of all of the rela-tive angles of the enclosures above.

2.3 Adjusting Horizontal Angles

When using the ATM Fly-WareTM MEGS-4000-Tgrid, the horizontal shape (the splay angles be-tween array columns) of a loudspeaker array is

FIGURE 13 - THE RELATIVE ENCLOSURE ANGLES

ADD IN A COLUMN

POSITION 1 - 2 (-5.4)

POSITION 1 - 5 (-3.6)

-9.0

POSITION 2 - 2 (-7.2)

-16.2

-3.6

Xrss

Xrsl

Xrsl

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easily set by coupling the grids together. TheATM grid and couplers are shown in Figures 8eand 8f. The splay angle between array columns isdetermined by the position of the couplers withinthe grids front and rear bars, which is illustratedin Figure 8g. The front and rear couplers may beswapped to attain small or 0 splay angles, as

shown inFigure 8h.2.4 Load Distribution Front to Back

Array Load Distribution: Within the X-Arrayflying system, the ratio of the total load supportedby the rear hinges versus the front straps is im-portant, because the front rigging straps have alower working-load limit then the rear rigginghinges. The ratio of the total load supported bythe front versus the rear rigging hardware is de-pendent on the location of the center of gravity ofthe assembly of enclosures in an array column.Two grid hinges are capable of supporting theentire load of an array column weighing 726 kg(1,600 lb) while maintaining a safety factor of 8:1with no contribution from the front straps. Twofront rigging straps are capable of supporting theentire load of an array column weighing 454 kg(1,000 lb) while maintaining a safety factor of 8:1with no contribution from the rear hinges. It is pos-sible that some array shapes will transfer most orall of the weight of a column to the front or to therear rigging hardware, therefore it is not valid toassume that the total weight will be distributedevenly over all four attachment points and to sim-ply add up the individual working-load limits of

each piece of rigging hardware to determine howmuch total weight may be suspended. Distributingthe majority of the weight of an array column tothe rear is desirable because of the higherstrength of the grid hinges and linking hinges.

If the total weight of a column of loudspeakers is

454 kg (1,000 lb) or less, the user typically neednot be concerned about the weight distributionfront to back because the front rigging strapswould be capable of supporting the entire weightof the column while maintaining a safety factor inexcess of 8:1. If the total weight of a column ofloudspeakers is greater than 454 kg (1,000 lb) but less than the 726-kg (1,600-lb) maximum the user must be concerned about the weight dis-tribution front to back to ensure that a safety fac-tor of 8:1 is maintained in the front rigging straps.Typically, the most common array configurationsused in touring and permanent-installation appli-cations, do distribute the majority of the weight ofan array column to the rear.

Some common shapes of array columns areshown in Figure 14. The center of gravity of arraycolumns, such as the one shown in Figure 14a, inwhich there are no enclosures angled upward andthere are no pull ups, is located towards the rearof the column. The weight distribution of thesetypes of arrays is always towards the rear of theenclosures throughout the column, resulting in themajority of the load being supported by the stron-ger rigging hinges than the less-strong riggingstraps. In these cases, the user need not haveany concern for the weight distribution other thanto balance a grid.

The center of gravity for array columns, such asthe one shown in Figure 14b, in which the top twoenclosures are angled upward, is located moretowards the front for the top enclosure. This shiftsmuch of the load from the stronger rear hinges tothe less-strong rigging straps. In these cases theuser must be concerned about the weight distri-bution front to back to ensure that too much loadis not applied to the front straps. As mention be-fore, the user need only be concerned if the totalweight of a column of loudspeakers is greaterthan 454 kg (1,000 lb). Electro-Voice recom-mends that no more than the top two X-Arrayenclosures in a column be angled upwards, andthat the upward angle is no greater than 15 toensure that a safety factor of 8:1 is maintainedin the front rigging straps.

The reader should note that the rating examplesgiven above are valid for when the rigging hingesand straps are loaded at nearly 0 vertically. Thereader is cautioned that the strength ratings of therigging hardware varies with angle, and shouldconsult section 3. Rigging-Strength Ratings,Safety Factors and Special Considerationsfor a

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detailed discussion of the structural strength ofthe rigging hardware.

Balancing the Grid: When using a grid, asshown in Figure 14, the pickup point on the grid(the hanger) must be positioned directly abovethe combined center of gravity for the entire col-

umn of enclosures so that the grid will be bal-anced and hang level. With enclosures facingstraight ahead or angled down, as shown inFigure 14a, the grid hanger must be shifted to-wards the back to be located directly above thecombined center of gravity for the entire column,so that the grid will be balanced and hang level.With enclosures angled up, as shown inFigure 14b, the grid hanger must be shifted for-ward. To ensure maximum stability, Electro-Voicerecommends that the grid be level 5. (SeeFigure 8c for hanger front-to-back adjustmentdetail for the ATM grid.)

2.5 Using Pull-Up LinesPull-Up Line Techniques: In a column ofX-Array loudspeakers, the rear rigging hingesallow the enclosures to pivot vertically (to angleup or down) while the front rigging straps set thevertical angles. The rigging straps can only con-strain the downward angle to resist gravity. Inother words, if, in an array column, there wereonly rear hinges and there were no front riggingstraps at all, each enclosure in the column wouldnaturally point downward due to gravity. The pre-cise downward angle of each free-hanging enclo-

sure would be dependent on the center of gravityof that enclosure and the weight of all of the en-closures suspended beneath it. The front riggingstraps can be used to limit the angle to less thanthat which gravity would dictate, but the front rig-ging straps cannot be used to increase the anglebeyond which gravity would naturally allow theenclosure to hang. Therefore, if a pair of front rig-ging straps on an enclosure were installed intrack positions that would enable a greater down-ward angle than gravity would allow, those riggingstraps would be slack when the enclosure wasfree hanging. To force that enclosure to angledown more than gravity would allow, a pull-upline would need to be attached to the bottomof the enclosure at the rear.

Pull-up lines are usually attached to the bottomback corner of the bottom enclosure in an arraycolumn. Pulling back and up will force the enclo-sure to angle down more until the front straps aretaut. Even if the enclosure with the slack frontstraps is not at the bottom of an array column,pulling back and up on the bottom enclosure willforce that enclosure down until the straps are taut.It should be noted that, because the relativeangles between the enclosures are limited by thefront rigging straps, a pull-up cannot further in-crease the angles between the enclosures wherethe front rigging straps were already taut, it willonly further tilt down the enclosures with the slackstraps. An example requiring a pull-up line is illus-trated inFigure 15.

When the lower enclosures in a vertical array re-quire relative downward angles greater than the18 maximum permitted by the Xrsl long riggingstraps, the front straps may be omitted from thoseenclosures. A pull-up line attached to the bottomenclosure can then be used to set the downwardangles of the lower enclosures, as shown inFigure 16, as long as the working-load limit of theXrhl linking hinges is not exceeded.

When a significant downward angle is required forthe top enclosure in an array column, the top en-closure should be attached directly to a structuralsupport (such as a building or a large customgrid) using a pair of Xrhp pickup hinges at therear. A pull-up line can the be used to pull thetop enclosure to the required angle, as shown inFigure 17. Custom front wire-rope straps utilizingthe New Haven NH32102-2 double-stud fittingscan then be added to the front of the top of theenclosure as redundant safety lines. Less then 1"of slack in the front safety straps is recom-mended. In applications where the total weight ofthe column is no greater then 454 kg (1,000 lb),custom wire-rope straps utilizing the New HavenNH32102-2 double-stud fittings may be used inplace of the pickup hinges at the rear of the top.

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This configuration cannot be implemented with agrid like that shown in Figure 8 because the gridcannot be balanced.

To attach a pull-up line to the bottom enclosurein an array column, a long Xrsl rigging strap(orother similar strap) may be attached to the tworound cutouts in the rear rigging track as shown

in Figure 18. A variety standard rigging hardwarecomponents (such as shackles, threaded chainconnectors, carabiners, etc.) may be used to se-cure the pull-up line to the Xrsl wire-rope strap.The attachment hardware should have a diameterof at least 9.5 mm (.375 in.) to eliminate the possi-bility of kinking the wire rope of the Xrsl. Attachingthe pull-up to only one of the round cutouts in therear track is not recommended because it wouldcause the column to twist.

CAUTIONS for Pull-Up Lines: When a grid isused, the Xrhg grid hinge is used to attach theback of the top enclosure in a column to the back

of the grid, while the Xrss or Xrsl rigging strapsare used to attach the front. If too much force isapplied on a pull-up line, the chain on the Xrhggrid hinges could go slack, shifting all of theweight of the entire array column to the front rig-ging straps. This condition presents two problemsof serious concern. The first concern is that, whenall of the weight shifts to the front straps, the gridwill become unbalanced, resulting in the front ofthe grid tilting down and the back tilting up. Thisimbalance could cause a sudden shift in the loadthat could be dangerous. If multiple grids are

coupled together horizontally and one grid be-comes unbalanced, there could be dangeroustwisting forces between the unbalanced grid andadjacent balanced grids. The second concern isthat, when all of the weight shifts to the frontstraps, a safety factor of 8:1 may not be main-tained for the front rigging straps.

When a grid is not used, the Xrhp pickup hingeis used to attach the back of the top enclosureto building structural supports, while custom wire-rope assemblies are used to support the top en-closure front. If too much force is applied on apull-up line, the chain on the Xrhp pickup hingescould go slack, shifting all of the weight of the en-tire array column to the front wire-rope assem-blies. The concern here is that, when all of theweight shifts to the front straps, a safety factor of8:1 may not be maintained for the front wire-ropeassemblies.

THE USER IS CAUTIONED TO TENSION THE

PULL-UP LINE ONLY UNTIL THE SLACK IN THEFRONT RIGGING STRAPS HAS BEEN RE-MOVED. NEVER PULL UP ENOUGH TO CAUSETHE CHAIN OF ANY Xrhg GRID HINGES ORXrhp PICKUP HINGES TO GO SLACK.

3. RIGGING-STRENGTH RATINGS, SAFETYFACTORS, AND SPECIAL SAFETY CONSIDER-ATIONS

3.1 Working Load Limit and Safety Factors

Definitions: The structural ratings for all of theX-Array rigging components and complete

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loudspeaker systems are based on test resultsin which parts were stressed to failure. Manu-facturers typically present the structural-strengthratings of mechanical components or systems

as either the working-load limit (WLL) or the ulti-mate-break strength. Electro-Voice chooses topresent the structural-load ratings of theX-Array loudspeaker systems as the working-load limit. The working-load-limit rating representsthe maximum load that should ever be applied toa mechanical component or system. THE USERSHOULD NEVER APPLY A LOAD THAT EX-CEEDS THE WORKING-LOAD LIMITS OF ANYOF THE RIGGING COMPONENTS OR COM-PLETE LOUDSPEAKER SYSTEMS DESCRIBEDIN THIS MANUAL.

The working-load limits for the X-Array riggingcomponents and complete loudspeaker systemsdescribed in this manual are based on an 8:1safety factor. The safety factor is defined as theratio of the ultimate-break strength divided by theworking-load limit, where the ultimate-breakstrength represents the force at which a part willstructurally fail. For example, if a part has work-ing-load limit of 454 kg (1,000 lb) based on an 8:1safety factor, it would not structurally fail until aforce of at least 3,629 kg (8,000 lb) was applied;however, the user should never apply a load tothat part that exceeds 454 kg (1,000 lb). Thesafety factor provides a margin of safety above

the working-load limit to accommodate normaldynamic loading and normal wear.

CAUTIONS for Working-Load Limits andSafety Factors: The working-load limits definedby the manufacturer of any rigging componentshould never be exceeded. Electro-Voice basesthe working-load limits of its products on an 8:1safety factor. Other manufacturers of rigging com-ponents may base their working-load limits onsafety factors other than 8:1. For example, 5:1safety factors are fairly common amongst riggingmanufacturers because many regulatory agen-

cies call for a minimum safety factor of 5:1.

When an X-Array loudspeaker system is in-stalled where local regulations only require asafety factor of 5:1, Electro-Voice insists that theworking-load limits of the X-Array componentsnever be exceeded, resulting in a safety factor of

8:1 still being maintained for the Electro-Voicecomponents. The user is cautioned that some lo-cal regulations may require safety factors higherthan 8:1. In that circumstance, Electro-Voice in-sists that the user maintain the higher safety fac-tor as required by the local regulations throughoutthe entire X-Array installation. It is the responsi-bility of the user to make sure that any X-Arrayinstallation meets any applicable local, state orfederal safety regulations.

3.2 Structural Rating Overview

There are two independent strength ratings that,together, give a complete description of the overall

structural performance capabilities of any X-Arrayloudspeaker system. They are defined as follows:

1. The strength of each individual riggingpoint; which is the combined strength of therigging track mounted on the enclosure withthe removable rigging-hinge and/or rigging-strapassemblies.

2. The total strength of the overall enclosure;which is a function of the combined forces from allof the rigging points acting on the enclosure as awhole.

The array designer must be aware of the working-load-limit ratings and the loads being applied tothe individual rigging points and the overall enclo-sure. An X-Array loudspeaker system is only asstrong as its weakest link. It is usually the casethat one of the working-load limits will be ap-proached sooner that the other. WHEN SUS-PENDING ANY X-ARRAY LOUDSPEAKERSYSTEM OVERHEAD, THE WORKING-LOADLIMITS MUST NEVER BE EXCEEDED FOREACH INDIVIDUAL RIGGING POINT, OR THEOVERALL ENCLOSURE.

The forces acting on each individual rigging pointand on the overall enclosures in an X-Array fly-ing system will vary with each array configuration.Determining the forces throughout an arrayrequires complex mathematical calculations.Electro-Voice engineers have, however, defineda set of simplified structural-rating guidelinesthateliminate the need for the complex calculationsfor most array configurations. The interaction ofthe complex forces throughout arrays were ana-lyzed to develop this set of conservative guide-lines, presented below, to enable a rigger to

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immediately determine on site whether or not anarray is safe without having to make weight-distri-bution calculations. The structural strength ratingsof the individual rigging points and the overallX-Array enclosures are also presented belowso that a complex structural analysiscan be madefor any array configuration. The reader shouldconsult an experienced structural engineer toperform the complex structural analysis.

The reader is directed to section 5. Referencesof this manual for a list of rigging references (forbackground in general rigging practice) and me-chanical engineering references (for backgroundin structural engineering analysis).

3.3 Simplified Structural-Rating Guidelines

The Guidelines: Electro-Voice engineers havedefined a set of simplified structural-rating guide-lines that will enable a rigger to immediatelyevaluate the safety of an X-Array system on

site without having to make complex force-distri-bution calculations. A combination of destructivetesting and computer modeling were used to ana-lyze the complex forces throughout arrays.Conservative working-load ratings were utilized tosimplify the guidelines. Therefore, array configu-rations other than those illustrated in these simpli-fied guidelines may be permissible for thoseapplications, consult section 3.4 Complex Struc-tural-Rating Analysisfor a detailed structuralanalysis.

The simplified structural-rating guidelines areshown in Figure 19. (Note that there is a label on

the back of each flying X-Array loudspeakerenclosure that includes the graphics shown inFigure 19.) These guidelines provide a simplifiedrating for typical arrays based on the:

1. Vertical angle of each enclosure

2. Total weight of that enclosure plus all of theenclosures and rigging hung below it.

3. Relative side-to-side and front-to-back anglesof the front Xrss or Xrsl rigging straps, orany custom front rigging straps.

4. Relative side-to-side angles of the Xrhg grid

hinges or Xrhp pickup hinges.

Figure 19 includes a graph of the working-loadweight-versus-angle limit rating for the X-Arrayenclosures. This working-load weight limit is appli-cable to every enclosure in an array, and includesthe weight of that enclosure plus the total weightof all enclosures and rigging hardware suspendedbelow it. The absolute enclosure angle is the ver-tical angle of that enclosure, where 0 representsan upright enclosure facing straight ahead

(0-elevation angle). These working-load-versus-angle limits take into account the complex forcesgenerated in the front rigging straps, the rear rig-ging hinges, the enclosure and the (optional) pull-up line, as a result of the complex weightdistribution throughout the array.

Also included in the simplified structural-ratingguidelines in Figure 19are side-to-side and front-to-back angle limits for the front rigging straps onthe top enclosure. These limits apply to the Xrssand Xrsl rigging straps, as well as any customwire-rope rigging straps used at the front of thetop enclosure.

In addition, the guidelines in Figure 19 include aside-to-side angle limit for the Xrhg grid hingesand the Xrhp pickup hinges. Front-to-back limitsare not necessary for the Xrhg and Xrhp hinges.The Xrhl linking hinges do not require any specificangle limits, because the front-to-back angles are

taken into account by the enclosure weight-ver-sus-angle ratings, and side-to-side angles are im-possible to achieve with the linking hinges.

CAUTIONS for the Simplified Structural-RatingGuidelines: WHEN APPLYING THE SIM-PLIFIED STRUCTURAL-RATING GUIDELINESTO ANY X-ARRAY LOUDSPEAKER SYSTEMSUSPENDED OVERHEAD, THE USER MUSTOBEY THE FOLLOWING RULES:

1. Never exceed the working-load-versus-angle limit for any enclosure in the array.

2. For the top enclosure, never exceed the side-to-side angle limit or the front-to-back anglelimit for the Xrss rigging strap, the Xrsl riggingstrap or any custom rigging strap.

3. For the top enclosure, never exceed theside-to-side angle limits for the Xrhg gridhinges or the Xrhp pickup hinges.

4. Always make sure that the hinge lockingpins on every Xrhl linking hinge, Xrhg gridhinge and Xrhp pickup hinge are fully en-gaged in the rigging track on the back ofevery enclosure (and grid, when applicable)before lifting overhead.

5. Always make sure that the double-stud fit-tings on every Xrss rigging strap, Xrsl rig-ging strap or any custom rigging strap aresecurely locked in the rigging track on thefront of every enclosure (and grid, whenapplicable) before lifting overhead.

6. Never angle more than the top two enclo-sures up in any array column. All other en-closures must be pointed straight ahead orat a downward angle.

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UP

XrhlLINKINGHINGE

Xrss,XrslORCUSTOM

RIGG

INGSTRAPS

XrhgORXrhpRIGGIN

GHINGES

XrssOR

XrslRIGGING

STRAPS

FRONTSTRAPSMAYBE

ELIMINATEDFORGREATER

DOWNWARDANGLES

NEVEREXCEEDRIGGING

-STRAP-ANGLE

ORRIGGING-HINGE-ANG

LELIMITSFOR

TOPENCLOSURE.

CAUTION

NEVEREXCEEDWORK

ING-LOAD-

VERSUS-ANGLELIMITF

OR

ANYENCLOSURE.

CAUTION

DOUBLE-STUD

FITTINGSMUST

BESECURELYL

OCKEDINTRACK

BEFORELIFTINGOVERHEAD.

CAUTION

CAUTION

DOWN

NEVERANGLE

MORETHANTWO

ENCLOSURESUP

CAUTION

WHEN

PULLINGUP,NEVER

ALLOW

RIGGINGHINGE

CHAIN

STOGOSLACK.

CAUTION

TOTALWEIGHTOF

ENCLOSUREPLUSALLENCLOSURESANDRIGGI

NGBELOW

VERSUSANGLE

WORKING-LOADLIMITVERSUSANGLEFOREACHENCLOSURE

15

10

5

0

-10

-20

-30

-40

-50

-60

-80

-70

-90

200

400

600

800

1000

1200

1400

1600

TOTALWEIGHT(LB)

NOTALLOWED

DOWN

UP

ABSOLUTEENCLOSUREANGLES

TOTALWEIGHT(KG)

NOTALLOWED

454

726

635

544

91

181

272

363

RIGGING-STRAP-

ANGLELIMITSFOR

TOPENCLOSUR

E

10

MAX

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EVIEW

REARVIEW

XrhgORXrhpRIGGING-

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FORTOPENCLOSURE

10

MAX

TYP

SIMPLIFIEDRIGGING

-RATINGGUIDELINES

DETERMININGTHEFORCESTHROUGHOUTANARRAYREQUIRES

COMPLEXCALCULATIO

NS.THESEGUIDELINESELIMINATETHENEED

1.THESESIMPLIFIEDRIG

GING-RATINGGUIDELINESPROVIDE

RATINGSFORTYPICAL

ARRAYSBASEDONTHE:

A.VERTICALANGLE

OFEACHENCLOSURE.

B.TOTALWEIGHTO

FEACHENCLOSUREPLUSALL

ENCLOSURESAN

DRIGGINGSUSPENDEDBELOW

IT.

C.RELATIVEANGLESOFTHEFRONTRIGGINGSTRAPS.

D.RELATIVEANGLE

OFTHEXrhgORXrhpHINGES.

WORKING-LOADRATIN

GS.OTHERARRAYCONFIGURATIONSMAYBE

FORWEIGHT-DISTRIBU

TIONCALCULATIONSBYUTILIZINGCONSERVATIV

E

PERMISSIBLE-FORTH

OSEAPPLICATIONS,CONSULTTHEX-ARRAY

FLYING

MANUALFORD

ETAILEDSTRUCTURALANALYSIS.

5.READTHEX-ARRAYFLYINGMANUALBEFORE

6.ALLNON-ELECTRO-VO

ICEHARDWAREISTHE

SUSPENDINGANYLOU

DSPEAKERSOVERHEAD.

RESPONSIBILITYOFOTHERS.

3.ONLYUSENEW

HAVEN

NH32102-2FITTINGSONRIGGINGSTRAPS.

4.ONLYUSEELECTRO-VOICEXrhg,XrhpandXrhlRIGGINGHINGES.

-+

2.WHENUSINGAGRID,A

LWAYSBALANCETHEGRIDSOITISLEVEL

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L

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2.NEVERPULLUPENOUGHT

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CAUSE

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GE

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SLACKOUTOFFRONTSTR

APS.

CAUTION

HINGELOCKINGPINSMUST

BEFULLYENGAGEDINTRACK

BEFORELIFTIN

GOVERHEAD

RIGGINGHINGEINSTALLATION

XrhgGRIDHINGESOR

XrhpPICKUPHINGES

XrhlLINKINGHINGES

1.INSTALLTHEREARHINGES.(THEREARHINGESARE

2.INSTALLTHEFRONTSTRAPSTOSETTHERELA

TIVE

3.IFANYENCLOSURESDONOTANGLEDOWNFA

RENOUGH,

THEPRIMARYSTRUCTURALSUPPORT.)

ANGLEBETWEEN

ENCLOSURESANDGRID.

LEAVINGSLACKINTHEFRONTSTRAPS,USEA

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.

RIGGINGINSTRUCTIONS

(APPROXIMATELY1.8

PERTRACKPOSITION.)

O

FIGURE19-S

IMPLIFIEDRIGGING-RATINGGUIDELINES

page 18


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7. When using pull-up lines, never pull upenough to allow the chains to go slack onthe rear Xrhg grid hinges or Xrhp pickuphinges.

8. When using a grid, always make sure thatthe grid is balanced and hangs level 5.

9. Only use New Haven NH32102-2 double-stud swivel-ring fittings on the Xrss riggingstraps, Xrsl rigging straps or any customrigging straps.

10. Only use Xrhl linking hinges, Xrhg gridhinges, or Xrhp pickup hinges manufac-tured by Electro-Voice.

Discussion of Array Examples: As an example,if the top enclosure in a column was angled down10, the enclosure working-load-versus-angle limitfrom the simplified structural-rating guidelinesshown in Figure 19 would indicate that a total of726 kg (1,600 lb) could be safely suspended including the weight of the top enclosure plus all

of the enclosures and rigging suspended below.If, however, the top enclosure in a column wasangled up 10, the total allowable weight wouldthen only be 499 kg (1,100 lb) including theweight of the top enclosure plus all of the enclo-sures and rigging suspended below. The enclo-sure working-load-versus-angle limit shown inFigure 19 not only applies to the top enclosure inan array column, but also applies to every enclo-sure in an array column. In arrays where a pull-upline is not used, the top enclosure is always the

limiting factor because it supports the mostweight. However, in arrays where a pull-up line isused to achieve substantial downward angles, it ispossible that a lower enclosure could be the limit-ing factor.

3.4 Complex Structural-Rating Analysis

For a complete structural-rating analysis, theforces in each individual piece of rigging hard-ware throughout the X-Array system must bedetermined, as well as the forces on each enclo-sure. Determining these forces requires complex

+

+

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mathematical calculations. All of these forcesmust then be compared to the working-load limitsdetailed below for each of the rigging points andthe overall enclosures. The reader should consultan experienced structural engineer to perform thecomplex structural analysis. WHEN SUSPEND-ING ANY X-ARRAY LOUDSPEAKER SYSTEMOVERHEAD, THE WORKING-LOAD LIMITSMUST NEVER BE EXCEEDED FOR EACH INDI-VIDUAL RIGGING POINT, AND THE OVERALLENCLOSURE.

Rear Rigging Structural-Strength Ratings: Theworking-load limit of each individual rigging pointon the rear of an X-Array enclosure is depen-dent upon the rigging-track/bracket assembly as itis mounted in the enclosure, the specific remov-able rigging-hardware assembly and the angle ofpull. The structural-strength ratings for the Xrhggrid hinge, Xrhp pickup hinge, Xrhl linking hingeand New Haven NH32102-2 fitting are shown inFigure 20.

The Xrhg grid and Xrhp pickup hinges have iden-tical structural-strength ratings, as shown inFigure 20a. It should be noted that the front-to-back-angle range is only 270 because the hingechains can only be put into tension and the enclo-sure prevents a full 360 rotation. It also shouldbe noted that the Xrhg grid and Xrhp pickuphinges are rated only to be used over side-to-sidepull angles of a maximum of 10 as shown inFigure 20a. The front-to-back ratings are validover the entire side-to-side range of 10.

The front-to-back structural-strength ratings forthe Xrhl linking hinges shown in Figure 20b covera full 360 rotation. Although it is not possible toput the hinge into tension over 360, it is possiblefor the linking hinges to go into compression whenpull-up straps are employed. Therefore, the 360rating is necessary to accommodate both tensionand compression. It also should be noted that theXrhl linking hinges are rated only to be used overside-to-side pull angles of a maximum of 5 asshown in Figure 20b. The front-to-back ratings arevalid over the entire side-to-side range of 5.

The structural-strength ratings for the New HavenNH32102-2 fitting, shown in Figure 20c, do notvary with the angle of pull both side to side andfront to back. Therefore, only a single rating isstated instead of a graph showing variations withangles.

It should be clarified that all of the structural-strength ratings shown in Figure 20are for a

single rear rigging point. There are, however, tworear rigging points on the enclosure each hav-ing the structural-strength ratings shown inFigure 20. The rear rigging strength ratings areidentical for all of the X-Array loudspeakermodel enclosures.

Front Rigging Structural-Strength Ratings:The working-load limit of each individual riggingpoint on the front of an X-Array enclosure is de-pendent upon the rigging-track/bracket assemblyas it is mounted in the enclosure, the New HavenNH32102-2 double-stud fitting and the angle of

+

+

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pull. The Xrss short wire-rope rigging strap, Xrsllong wire-rope rigging strap and New HavenNH32102-2 fitting have identical structural-strength ratings as shown in Figure 21. Theratings vary with both the side-to-side and front-to-back angles and, therefore, are illustrated withtwo graphs. The rigging straps and/or fittings have

a side-to-side range of 360; however, the front-to-back range is only 270 because the enclosureprevents a full 360 rotation.

It should be clarified that all of the strength ratingsshown in Figure 21 are for a single front riggingpoint. There are, however, two front rigging pointson the enclosure each having the structural-strength ratings shown in Figure 21. The front rig-ging strength ratings are identical for all of theX-Array model enclosures.

Overall Enclosure Structural-Strength Ratings:The actual strength of an X-Array enclosure will

depend on the complex total of the combinedforces from each of the rigging points acting onthe enclosure as a whole and will vary with thearray configuration. However, for the sake of sim-plicity, Electro-Voice chooses to define the work-ing-load limit of the overall enclosure as the sumtotal of the weight of that enclosure plus theweight of all of the enclosures and rigging hard-ware suspended below. This simplified working-load weight rating for the overall enclosure,shown in Figure 22, is defined as being inde-pendent of the angles of pull on the individual rig-ging points. The Electro-Voice engineers havechosen to define the working-load limits of the in-dividual rigging points as a function of pull angleso that they take into account any variations inenclosure strength that might occur as a functionof pull angle. This approach allows the enclosureworking-load limit to be defined as independent ofpull angles, making the complex structural-ratinganalysis easier. The enclosure strength ratingsare identical for all of the X-Array models.

CAUTIONS for a Complex Structural RatingAnalysis: WHEN APPLYING A COMPLEXSTRUCTURAL-RATING ANALYSISTO ANYX-ARRAY LOUDSPEAKER SYSTEM SUS-PENDED OVERHEAD, THE USER MUST OBEYTHE FOLLOWING RULES:

1. For the front of every enclosure in an array,never exceed the working-load-versus-angle limit for the Xrss rigging straps, theXrsl rigging straps or any custom riggingstraps.

2. For the back of every enclosure in an array,never exceed the working-load-versus-angle limit for the Xrhl linking hinges, the

Xrhg grid hinges, Xrhp pickup hinges or anycustom rigging straps.

3. Always make sure that the hinge lockingpins on every Xrhl linking hinge, Xrhg gridhinge and Xrhp pickup hinge are fully en-gaged in the rigging track on the back of

every enclosure (and grid, when applicable)before lifting overhead.

4. Always make sure that the double-stud fit-tings on every Xrss rigging strap, Xrsl rig-ging strap or any custom rigging strap aresecurely locked in the rigging track on thefront of every enclosure (and grid, whenapplicable) before lifting overhead.

5. When using pull-up lines, never pull upenough to allow the chains to go slack onthe rear Xrhg grid hinges, the Xrhp pickuphinges or any custom rigging strap assem-bly.

6. When using a grid, always make sure thatthe grid is balanced and hangs level 5.

7. Only use New Haven NH32102-2 double-stud swivel-ring fittings on the Xrss riggingstraps, Xrsl rigging straps or any customrigging straps.

8. Only use Xrhl linking hinges, Xrhg gridhinges, or Xrhp pickup hinges manufac-tured by Electro-Voice.

3.5 Special Considerations

Double-Stud Fittings: All of the X-Array mod-els will accept the standard aircraft-type double-stud fittings in the rear as well as the front riggingtracks. Electro-Voice recommends using only theNew Haven NH32102-2 double-stud swivel-ringfitting with X-Array loudspeaker systems be-cause it is the only double-stud fitting that has asecondary locking mechanism (an additional lock-ing pin) that eliminates the possibility of the fittingvibrating loose from the rigging track. In addition,Electro-Voice recommends using the NH32102-2double-stud fitting for attachment to the front rig-

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ging track when custom wire-rope rigging strapsare required. The standard Xrss and Xrsl wire-rope rigging straps use the NH32102-2 fitting.

The Xrhp pickup hinge is typically recommendedin applications where no grid is used, however,custom wire-rope assemblies using the NH32102-

2 double-stud fitting may be substituted in lightduty applications where the total weight sus-pended is 454 kg (1,000 lb) or less. When liftingcolumns weighing more than 454 kg (1,000 lb) but less than 726 kg (1,600 lb) the Xrhp pickuphinge must be used.

Flying a Single Enclosure: When linked to-gether in columns, X-Array enclosures mustalways be suspended vertically (in other words,the enclosures may be suspended upside downor right side up, but never sideways). However,a single enclosure may be suspended without agrid in any orientation vertically (right side up or

upside down) or horizontally (sideways). Becausethe weight of a single enclosure is below theworking-load limits of the individual rigging pointsand the overall enclosure, the enclosure can besuspended in any configuration. Several possibili-ties are shown in Figure 23. Custom wire-roperigging-strap assemblies would typically be em-ployed using the New Haven NH32102-2 double-stud fittings for this application. It should be notedthat all of the configurations shown in Figure 23are not specifically covered in section 3.3 Simpli-fied Structural-Rating Guidelines, as shown inFigure 19. These configurations would, however,be covered in section 3.4 Complex Structural-Rat-ing Analysis.

3.6 Electro-Voice Structural-Analysis Proce-dures

Electro-Voice maintains a structural pull-test facil-ity in Buchanan, Michigan USA which includesload cells with digital-electronic display and re-cording. The load cells are calibrated annually byan independent laboratory to a standard traceableto the United States National Bureau of Stan-dards. This pull-test facility is capable of pulling todestruction individual rigging components as wellas complete loudspeaker systems. This facility is

utilized by the design engineering group to testengineering prototypes, and by the manufacturingquality assurance group for testing productioncomponents and systems.

Electro-Voice utilizes state-of-the-art computer-modeling programs for structural analysisthroughout the development of loudspeaker sys-tems. The computer modeling enables the com-plex forces in the rigging components andenclosures to be analyzed for loudspeakers as-sembled into arrays in both static and dynamicconditions.

Structural testing and computer modeling wereused throughout the engineering development ofall of the X-Array individual rigging componentsand complete loudspeaker systems described inthis manual. Testing and modeling involving bothanticipated use and anticipated misuse were per-formed as part of the analysis. Engineering proto-types were stressed to failure and designs wererevised based on those test results. Productionsystems and components were stressed to failurefor verification of the final designs.

4. RIGGING INSPECTION AND PRECAUTIONS

Electro-Voice X-Array Loudspeaker Sys-tems: Prior to each use, inspect the loudspeakerenclosures for any cracks, deformations, missingor damaged components which could reduce en-closure strength. Inspect the track and bracketassemblies on the enclosures for any cracks, de-formations, missing or loose screws which could

reduce the flying hardware strength. Replace anyloudspeaker systems that are damaged or miss-ing hardware. Never exceed the limitations ormaximum recommended load for the X-Arraysystems.

Electro-Voice X-Array Rigging Hinges: Priorto each use, inspect the rigging hinges for cracks,burrs, corrosion or missing or damaged compo-nents which could reduce hinge assemblystrength. Replace any rigging hinges that aredamaged or missing hardware. Always doublecheck that each rigging hinge is securely lockedinto position in the track on the X-Array enclo-

sures and grids before lifting. Never exceed thelimitations or maximum recommended load for theX-Array hinges.

Wire-Rope Rigging-Strap Assemblies: Prior toeach use, inspect the wire rope for cuts, abrasion,tears, fraying, knots, chemical damage, burns, orcorrosion which could reduce rigging strapstrength. Inspect the rigging fittings for anycracks, burrs, deformation, corrosion or missingor damaged components which could reduce fit-ting strength. Replace any rigging straps thathave damaged wire rope, or damaged or missinghardware. Always double check that each fitting

on each of the rigging straps is securely lockedinto position in the track on the X-Array enclo-sures and grids before lifting. Never exceed thelimitations or maximum recommended load for therigging strap assemblies.

Grid Assemblies: Prior to each use, inspect thegrid assembly and associated hardware for anycracks, deformations, broken welds, corrosion,missing or damaged components which could re-duce the grid assembly strength. Replace anydamaged grid assemblies. Never exceed the limi-tations or maximum recommended load intended

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for grid assembly design. Never exceed the limi-tations or maximum recommended load for thegrid assemblies.

Chain Hoists: Prior to

x-array flying manual

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