EM Acoustics ST-218 Operational manual

ST-218 Subwoofer
Product User Manual
v2 November 2019
LOUDSPEAKERS REDEFINED

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Contents
DECLARATION OF CONFORMITY ................................................................................................................5!
1.0 - Introduction ............................................................................................................................................. 6!
Unpacking.......................................................................................................................................................6!
2.0 – ST-218 & Accessories..........................................................................................................................7!
ST-218 ............................................................................................................................................................7!
FG-218 ............................................................................................................................................................7!
GS-HALO-A.....................................................................................................................................................7!
WC-T218.........................................................................................................................................................8!
Padded transit covers................................................................................................................................ 8!
Castor Set.......................................................................................................................................................8!
SAFETY-218..................................................................................................................................................8!
CHAIN-HALO-A .............................................................................................................................................8!
3.0 - Safety Considerations..........................................................................................................................9!
System Overview ........................................................................................................................................9!
IMPORTANT SAFETY CONSIDERATIONS ............................................................................................9!
Secondary Safeties.................................................................................................................................. 10!
Safety Inspections................................................................................................................................... 10!
4.0 – Simulation.............................................................................................................................................. 11!
Ease Focus 3 .............................................................................................................................................. 11!
5.0 – Rigging System Overview............................................................................................................... 12!
5.1 – ST-218 Cabinet Hardware Overview..................................................................................... 12!
5.2 - FG-218............................................................................................................................................... 13!
FG-218 Instruction Labels – Spine, Right Side......................................................................... 15!
6.0 – System Setup....................................................................................................................................... 16!
6.1 – Preparing ST-218 subwoofers for flying or stacking....................................................... 16!
6.1.1 – Extending the rigging links................................................................................................ 16!
6.1.2 – Cardioid Use............................................................................................................................. 17!
6.1.3 – Using the WC-T215 transit wheelcart........................................................................... 18!
6.2 – Flying ST-218 subwoofers......................................................................................................... 20!
6.2.1 – ST-218 subwoofers – single pickup, normal orientation......................................... 20!
6.2.2 – ST-218 subwoofers – single pickup, cardioid orientation....................................... 23!
6.2.3 – ST-218 subwoofers – dual pickup.................................................................................... 23!

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6.3 – Ground Stacking ST-218 subwoofers .................................................................................... 24!
6.3.1 – Using ST-218 subwoofers alone ..................................................................................... 24!
6.3.2 - Ground Stacking with HALO-A and the GS-HALO-A frame..................................... 25!
6.4 Using the CHAIN-HALO-A lifting chain ..................................................................................... 28!
6.5 – Fitting castors ................................................................................................................................. 29!
7.0 – Powering the System........................................................................................................................ 30!
7.1 - Amplifier and Processing Requirements............................................................................... 30!
7.1.1 - Connections............................................................................................................................. 30!
7.1.2 - Connector Options................................................................................................................. 30!
7.1.3 – Amplifier Requirements ...................................................................................................... 31!
7.1.4 – Processing Requirements................................................................................................... 31!
7.2 - Presets and Settings .................................................................................................................... 32!
7.2.1 – Standard ST-218 Preset ..................................................................................................... 32!
7.2.2 – Cardioid Array Preset............................................................................................................ 32!
7.2.2 - FIR Latency.............................................................................................................................. 33!
7.2.3 - Geometric Delay..................................................................................................................... 33!
7.2.4 - Applying EQ.............................................................................................................................. 33!
7.3 - Use with the DQ Series Advanced System Amplifiers ..................................................... 34!
7.3.1 - Connections............................................................................................................................. 34!
7.3.2 - Preset Recall............................................................................................................................ 34!
7.4 - System Connectivity..................................................................................................................... 35!
7.4.1 - Cable Length and Specification........................................................................................ 35!
7.4.2 - Available Cable Accessories............................................................................................... 35!
7.5 - Use with the DQRack.................................................................................................................... 37!
7.5.1 - DQRack Overview .................................................................................................................. 37!
7.5.2 - System Examples with the DQRack................................................................................ 38!
8.0 – Servicing Information........................................................................................................................ 40!
8.1 – ST-218: Removing the grille..................................................................................................... 40!
8.2 – ST-218: Removing the drive units ......................................................................................... 41!
8.3 – ST-218: Replacing a Rigging flying pin ................................................................................ 42!
Appendix A – Technical Specifications.................................................................................................. 43!
ST-218 large format flyable subwoofer.......................................................................................... 43!
Appendix B – Technical Drawings ........................................................................................................... 44!
Appendix C – Spare Parts List ................................................................................................................... 48!

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Appendix D – Warranty Information ....................................................................................................... 49!
Limited Warranty ................................................................................................................................. 49!
Warranty Coverage ............................................................................................................................. 49!
Returning your EM Acoustics loudspeaker................................................................................. 49!

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DECLARATION OF CONFORMITY
The products contained within this manual conform to the
requirements of the EMC Directive 89/336/EEC, amended by
92/31/EEC and to the requirements of the Low Voltage Directive
73/23/EEC amended by 93/68/EEC.
EMC Emission EN55103-1:1996
Immunity EN55103-2:1996
Electrical Safety EN60065:1993
RECYCLING
This product and its packaging constitute the applicable product according
to the WEEE directive. Please ensure that at the end of the working life of
this product, it is disposed of sensibly in accordance with local and national
recycling regulations. The packaging supplied with this product is
recyclable. Please retain all packaging, however if disposing of this
packaging please ensure that you comply with local recycling regulations.
These products also all comply to the RoHS Directive 2002/95/EC.

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1.0 - Introduction
Thank you for purchasing the ST-218 subwoofer from EM Acoustics. This product has been
designed and rigorously tested to give you the utmost in sonic performance and many
years of reliable, trouble-free operation. Please take the time to read this user manual
thoroughly to ensure you get the best performance from your system and to ensure you
set it up correctly and safely. If you have any questions or are in any doubt whatsoever
about any aspect of your new product, please do not hesitate to contact us directly or your
local EM Acoustics representative.
The ST-218 is a high-powered subwoofer, intended for a wide variety of low frequency
applications in larger format situations. The ST-218 is at home in permanent installations,
although with its rugged construction and flying system it is optimised for touring use.
Two state of the art neodymium 18” drive units provide effortless low frequency
extension and overall SPL capability within a rugged enclosure, and full flying hardware is
included. Various accessories are available to help you get the best out of this product –
from flying and stacking to transport and storage.
This manual contains all the information you should need on topics of set up, amplifier
connection, flying & stacking and basic service. If you feel we have missed anything, or
you have a question not covered by this manual, please visit our website
www.emacoustics.co.uk and send us a message or give us a call – we’re only too happy to
help.
Unpacking
Please take care when unpacking your loudspeaker system. Once unpacked, please inspect
each enclosure thoroughly for any transit damage and in the case of any damage please
notify your carrier immediately. It is the responsibility of you, the consignee, to instigate
any claim. Please retain all original packaging in case of future re-shipment.

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2.0 – ST-218 & Accessories
The ST-218 subwoofer has a range of accessories available for flying, stacking and
transport in different configurations.
ST-218
Large format touring subwoofer
FEATURES & BENEFITS
•Signature EM Acoustics “maximum headroom” design approach ensures
consistency of performance regardless of SPL level.
•Intuitive, simple 4-point flying system, assembled from ultra-high tensile
strength steel.
•Flying and stacking system allows assembly of cardioid arrays.
•Enclosure coated with 3-step polyurethane process - ensuring the cabinets
are not only weather resistant but more resilient to impact damage.
•Various features and accessories for easy moving & handling.
•Single amplifier channel required.
KEY SPECIFICATIONS
!
ENCLOSURE TYPE:
DRIVE UNITS:
FREQUENCY RESPONSE:
NOMINAL DISPERSION1:
MAXIMUM SPL:
NOMINAL IMPEDANCE:
DIMENSIONS (HxWxD):
NET/SHIPPING WEIGHT:
!
!
Large format flyable reflex subwoofer
2 x 18” neodymium LF drive units
28Hz - 150Hz +/-3dB
omniirectional
137dB continuous, 143 dB peak
2 ohms
550 (21.7) x 1300 (51.2) x 850 (33.5) mm/(ins)
111/114kg (244.4/250.8lbs)
FG-218
Master Flying Grid
The FG-218 is the master flying grid for the ST-218 subwoofer and
provides a means of safely and swiftly flying arrays of ST-218
subwoofers. Up to 12 ST-218 subwoofers can be safely flown in any
configuration with a safety factor of 10:1. The FG-HALO-B is supplied
with two pickup links to use as suspension points - it is strongly
recommended that arrays larger than four subwoofers use two lifting
points for control and ease of use.
The FG-218 is supplied with four 3.25t WLL bow shackles.
Weight (without shackles) 50kg / 110lbs
Weight (including supplied shackles) 52.6kg / 115.7lbs
GS-HALO-A
Ground Stack Frame
The GS-HALO-A allows for HALO-A enclosures to be safely rigged on
top of ST-218 subwoofers and can also be used as a stand-alone
ground stacking base plate.
HALO-A enclosures need to be inverted to mount on to the GS-HALO-
A, and a maximum of six HALO-A enclosures can be stacked on the GS-
HALO-A in this way.
When using the GS-HALO-A without attaching to ST-218 subwoofers,
the GS-HALO-A must be secured using ratchet straps or similar for
arrays larger than two elements.
Weight 26kg / 57.2lbs

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CHAIN-HALO-A
Extension Lift Chain
The CHAIN-HALO-A assembly is intended to go between a motor and
the FG-218 pickup link. It is a variable length chain, intended to give
extra vertical clearance to accommodate motor lift chain bags. It has
a SWL of 2.5 tonne and an effective maximum working length of
1000mm.
Weight 3kg / 6.6lbs
The SAFETY-218 assembly is a 2-leg bridle chain assembly, intended
to connect the two safety points on the FG-218 to a single point for
application of a secondary safety. It has an effective working length
of 600mm and the following SWL:
3.55 tonne 0-45 degrees
2.5 tonne 45-60 degrees
The angle between the chain legs must not exceed 60 degrees.
Weight 3.6kg / 7.9lbs
WC-T218
Transit Wheelcart
Designed to safely transport columns of up to three ST-2158
subwoofers ready to fly, the WC-T218 is a steel frame construction
wheelcart that allows the ST-218 to lock securely to it.
Subwoofers can be assembled in cardioid arrays as well as front-
facing, and the WC-T218 is sized to truck pack neatly.
Four individually braked castors and protective polymer bumpers
complete the touring package.
Weight 40.8kg / 89.8lbs
Padded transit covers
Three padded transit cover options are available for the ST-218:
TC-T218 single subwoofer cover, designed to protect individual units
when fitted with the optional castor set.
TC-T218-2 dual subwoofer cover, designed to protect pairs of ST-218
subwoofers when on the WC-T218 wheelcart.
TC-T218-3 triple subwoofer cover, designed to protect three ST-218
subwoofers when on the WC-T218 wheelcart.
SAFETY-218
Chainset
Castor Set
For single subwoofer transport, tour-grade castors can be fitted to the
rear of the enclosure to allow the ST-218 to be easily moved around.

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3.0 - Safety Considerations
System Overview
The flying system for the ST-218 has been specifically designed to be flexible, intuitive and reliable.
Please read this section of the user manual extremely carefully as the rigging of loudspeakers is a
very serious matter with potentially fatal consequences should anything go wrong. If you are in
ANY DOUBT WHATSOEVER, contact a reputable rigging company or your local EM Acoustics
representative.
IMPORTANT SAFETY CONSIDERATIONS
The ST-218 rigging system has been designed and constructed to a very high standard of safety,
and tested to demanding specifications. To ensure the highest standards of safety, the following
information on array assembly must be exactly followed and understood.
Only use EM Acoustics recommended rigging hardware and accessories, which are specifically
designed for the purpose. Do not use ST-218 flying hardware for any other loudspeaker system –
the components are specifically designed to work with the ST-218 product and are not
interchangeable with any other EM Acoustics loudspeaker product or any other loudspeaker system
unless clearly specified. The use of ST-218 flying hardware with other manufacturers’ systems may
compromise the safety standards and EM Acoustics is in no way liable for any loss, damage or injury
caused by such practice.
Do not modify or alter the ST-218 hardware or accessories, nor use them in any way other than that
described in this manual. Rigging components supplied as part of the ST-218 system are in no way
interchangeable and should not be used as such.
The component parts of the ST-218 rigging assembly should only be assembled in the manner
described in this manual, using the fasteners and fixings stated herein. The use of fasteners and
methods of assembly not described in this manual may result in an unsafe assembly and as such
EM Acoustics will not be responsible for any loss, damage or injury caused by such practice. Welding,
drilling or any other means of modifying any part of the flying hardware or permanently fixing
components to each other is strictly forbidden.
Rigging assemblies must only be assembled using the appropriate parts and fixings as described in
this manual, explicitly following the assembly instructions given herein. Rigging components must
only be fixed to EM Acoustics ST-218 subwoofers, using the correct cabinet location points,
assembly methods and fasteners specifically described within this manual.
Walls, floors and ceilings must be capable of supporting the actual load placed upon them. The
rigging hardware must be safely and securely fixed to both the loudspeaker system and the
supporting structure.

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Secondary Safeties
It is imperative that all loudspeakers flown in any given environment should be provided with a
second, independent and properly rated safety suspension point in addition to the principle load
bearing means of suspension. Steel wire ropes or steel chains of an approved construction and load
rating only may be used as secondary safeties. Plastic covered steel chains may not be used as
secondary safeties under any circumstances. Also ensure that all local and national laws are
complied with when determining your primary and secondary suspension points.
Safety Inspections
Carefully inspect all flying system components prior to use for defects or signs of damage prior to
assembling a HALO Arena array. If any components damaged or you suspect them to be damaged,
DO NOT USE THEM.
Regular scheduled tests – which are much more rigorous than visual inspections – of all rigging
components must also be carried out. Safety legislation, and test/inspection requirements, will vary
from country to country and as such it is the user’s responsibility to ensure that local regulations
are adhered to. In most cases, annual independent tests & inspections carried out by a suitably
approved and qualified inspector will be required.
EM Acoustics recommends detailed logbooks be kept of all inspections and load tests to ensure an
accurate record is kept of the testing for each EM Acoustics rigging accessory.
When flying any loudspeaker system, always wear protective headwear, footwear and eye
protection in accordance with local regulations.
The rigging of a flown loudspeaker system may be dangerous if not undertaken by a suitably
experienced and qualified rigger. Installation & fixing of all hanging points should only be
carried out by a professional rigger in accordance with local legislation as well as the rules of
the venue. The house rigger and/or venue manager must always be consulted.

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4.0 – Simulation
Ease Focus 3
For safety and acoustic reasons, it is advised that users familiarize themselves with Ease Focus 3.
Along with providing the user with accurate simulations for setting up ST-218 subwoofers, it also
provides importing safety information with regards to load limits.
Ease Focus 3 can be downloaded for free from the AFMG website at http://focus.afmg.eu and is
currently available as a stand-alone application for Windows (XP or Higher) only. It can also be
downloaded directly from the EM Acoustics website with all the current product files embedded.
Tutorials for Ease Focus 3 are available from with the application itself.
For training on the design and implementation of ST-218 subwoofers including the specific use of
Ease Focus 3, please contact your local distributor.

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5.0 – Rigging System Overview
5.1 – ST-218 Cabinet Hardware Overview
[2]
[4]
[6]
[1]
[3]
[5]
[7]
[5]
1
Lifting & Carrying Handle
2
Rigging Link (retracted)
3
Rigging Link Lock Pin
4
Enclosure Link Pin
5
Floor Runner
6
Stacking Recess
7
Castor Attachment Point
[6]

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5.2 - FG-218
[6]
[1]
[3]
[7]
[9]
[8]
[6]
[5]
[2]
[2]
[4]

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[1] – Front Link Attachment Point
[2] – Rear Link Attachment Point
[3] – Sub Link Attachment Point
[4] – Front Dual Pickup Location
[5] – Rear Dual Pickup Location
[6] – Safety Points
[7] – Pickup Links (Stowed)
[8] – Pickup Links (Normal Position)
[9] – Pickup Links (Cardioid Position)
This clevis forms the area where ST-218 enclosure links
should be engaged. A 0.375” ball-lock pin secures each
link in place.
This clevis forms the area where ST-218 enclosure links
should be engaged. A 0.375” ball-lock pin secures each
link in place.
When using two motors to fly the array, insert the rear
link into this location in the “normal” orientation.
A secondary safety must always be used on flown
arrays. Both safety points should be connected to avoid
the array swinging in the event of a primary lift failure.
The SAFETY-218 2-leg bridle is designed for this
purpose.
When using two motors to fly the array, insert the front
link into this location in the “normal” orientation.
Stow locations for the two pickup links when the FG-
218 is being stored or transported.
When using a single pickup point and a front-firing
conventional subwoofer array, use the link in this
orientation. This orientation is also used for both links
in dual pickup applications.
When using a single pick point and a cardioid array, use
the link in this orientation in the relevant location on
the FG-218 spine.
Single point pickup location. Two possible options are
available for picking up either a standard array or a
cardioid array, and position the pickup location directly
over the centre of gravity of the subwoofer array.

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FG-218 Instruction Labels – Spine, Right Side

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6.0 – System Setup
6.1 – Preparing ST-218 subwoofers for flying or stacking
6.1.1 – Extending the rigging links
Remove the Link Lock pin from
the top of each rigging assembly
Extend all four rigging links
Reinstate all four Link Lock pins to lock link in place
Safety label visible when link is retracted
Safety label hidden when link is correctly extended
Step 1.
Step 2.
Step 3.

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Standard subwoofer column
All subwoofers forward
Cardioid subwoofer column
One subwoofer in three reversed
6.1.2 – Cardioid Use
The ST-218 rigging locations are symmetrical front-to-back, so subwoofers can be
reversed to create cardioid arrays. Simply assemble the subwoofer stack or flown column
as normal but reverse every third subwoofer. The rigging hardware can and should be
engaged as normal.
For guidance on correct cabling for cardioid subwoofer arrays, see Chapter 7 of this manual.
IMPORTANT NOTE:
See sections 6.2.1 and 6.2.2 for information on the correct procedure when flying
normal or cardioid arrays from a single point.
For all sections of this manual describing flying or stacking ST-218 subwoofers, the
procedure is identical when assembling cardioid subwoofer arrays.

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6.1.3 – Using the WC-T215 transit wheelcart
Step 1.
Keeping the subwoofer the right way up, remove
the enclosure link pins from the bottom of each
rigging assembly.
Step 2.
Line the subwoofer up over the links on the
wheelcart, and lower into place ensuring that the links
engage into the clevises on the subwoofer. The
subwoofer will rest on the supports in the cart
structure.
Step 3.
Reinstate the enclosure link pins into all four corners of the cart to
lock the subwoofer to the wheelcart.

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Step 4.
If adding more subwoofers, simply stack the next
subwoofer on top of the first one. Ensure that the
protective runners on the lower sub have engaged in the
recesses in the upper one – this helps to ensure the
subwoofer is correctly located. Remove the Link Lock pins
on the lower subwoofer, and the Enclosure Link pins on the
upper subwoofer, and slide each link into the upper
position.
Step 5.
On each rigging assembly, reinstate both the Enclosure Link pin, and the
Link Lock pin. This ensures the second subwoofer is securely locked to
the first one and the cart is stable. There should not be any of the
rigging safety indicators visible where the two subwoofers meet.
Step 6.
This process can be repeated to add a third subwoofer if required.

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6.2 – Flying ST-218 subwoofers
6.2.1 – ST-218 subwoofers – single pickup, normal orientation
Step 1.
Prepare the FG-218 by locating a single pickup link into the “normal”
position as indicated by the main label and the label on the link. Ensure
the location arrows are lined up as shown.
(Label is on the right side of the flying grid)
Step 2.
Remove the four Enclosure Link pins from the FG-218.
Prepare the first ST-218 as detailed in
section 6.1.1 above so that the four
links are extended and locked in place.
Step 3.