Next LA12 User manual

USER’S GUIDE
LA12 & LA12C
Version 2.0

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TECHNICAL SUPPORT
If you have a question about line
arrays or run into a problem
using one of our line arrays,
call our technical support team.
Phone: [phone]
Monday through Friday between 8:30 AM and 6:30 PM.
E-mail: [email protected]

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Table of contents
TABLE OF CONTENTS...................................................................................................................................... 3
1. INTRODUCTION........................................................................................................................................ 5
1.1MAIN FEATURES..................................................................................................................................... 5
1.2 SYSTEM ENCLOSURE .............................................................................................................................. 6
1.3 BASS,MID AND HIGH SECTIONS.............................................................................................................. 6
1.4 BOX DESCRIPTION AND DIMENSIONS ...................................................................................................... 8
1.5 OUTDOOR EXPOSURE.............................................................................................................................. 9
1.6 INPUT CONNECTOR PANEL..................................................................................................................... 9
1.7 LA12 (LA12C) LINE ARRAY ELEMENT SPECIFICATIONS FOR A SINGLE ENCLOSURE ............................. 10
2. SYSTEM CONNECTION, AMPLIFICATION AND DIGITAL PROCESSING ............................... 12
2.1 POWER AMPLIFIER ............................................................................................................................... 12
2.2 NEXT LMS240I DIGITAL PROCESSOR.................................................................................................. 13
2.3 SPEAKER CABLE REQUIREMENTS......................................................................................................... 16
3. RIGGING.................................................................................................................................................... 17
3.1 SAFETY WARNING................................................................................................................................ 17
3.2 FLYING LOUDSPEAKERS SAFELY........................................................................................................... 18
3.3 GROUND STACKING LOUDSPEAKERS SAFELY........................................................................................ 19
3.4 TRAINING &EDUCATION ..................................................................................................................... 20
3.5 RIGGING SYSTEM OVERVIEW................................................................................................................ 20
3.6 FLYING HARDWARE.............................................................................................................................. 20
3.7 QUICK –RELEASE PINS ......................................................................................................................... 21
3.8 FLYING BAR.......................................................................................................................................... 21
3.9 SWING ARMS ........................................................................................................................................ 22
3.10 RIGGING SLOTS .................................................................................................................................... 22
4. RIGGING SETUP PROCEDURES ......................................................................................................... 23
4.1 FLOWN INSTALLATION ......................................................................................................................... 23
4.2 GROUND STACKING.............................................................................................................................. 26
5. MAINTENANCE ....................................................................................................................................... 28
5.1 RIGGING SYSTEM.................................................................................................................................. 28
5.2 ENCLOSURE CLEANING......................................................................................................................... 29
5.3 TRANSDUCERS ..................................................................................................................................... 29
5.4 SPARE PARTS........................................................................................................................................ 29

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PLEASE take a little time to learn how to get great results with your NEXT LA12
(LA12C) System. It’s a small investment that will generate a large payoff: more satisfied
clients, more efficient operations and better recognition for your skill as a sound
reinforcement professional.

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1. INTRODUCTION
NEXT-proaudio LA12 (LA12C) line array is a next generation line array system
which combine innovative loudspeaker design techniques with line array technology to
produce a very powerful with extended frequency response, smooth coverage and maximum
dynamic impact line array.
1.1 MAIN FEATURES
3 way all horn loaded Line Array system;
High SPL and low distortion;
Very smooth and clear sound;
Excellent and highly predictable dispersion control over a wide bandwidth;
Great and deep bass impact thanks to the double tuned bass cabinet;
One piece molded Mid/High section for strength and accuracy;

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Wide bandwidth (60Hz - 19kHz );
Wide and uniform horizontal dispersion (-6dB @ 90º);
Fast, simple Integrated Rigging hardware;
Rugged premium void free plywood outer shell;
Stand alone operation in most situations;
Integrated flying hardware.
1.2 SYSTEM ENCLOSURE
The system enclosure integrates the unique acoustical elements into a highly portable
and rugged physical system. To make field handling easier and to enable you to create very
large arrays, the individual box weight has been minimized without sacrificing strength,
safety, or audio quality. Each box of the LA12 (LA12C) line array weights just 54kg (46kg)
while containing one 700-watt low frequency driver, two 280-watt mid frequency drivers, and
three 60-watt, 1” diaphragm high frequency compression drivers. This weight includes the
attached rigging hardware.
1.3 BASS,MIDAND HIGH SECTIONS
The Bass section

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The LA12 (LA12C) line array system features a 12" Neodymium high excursion high
power bass loudspeaker loaded by a DOUBLE TECHNOLOGY CABINET that perfectly
matches the very high efficiency and impact of a horn reproduction with the soft extended
bass response of the reflex loading.
The Mid section
For the mid we use 2 special 6.5" speakers with two PRISMATIC PHASE
CORRECTION DEVICES, mounted in a 90º horizontal dispersion wave guide. The
prismatic phases devices besides the phase correction also makes the system behave like a
four sound sources and so agreeing with the second line arrays condition: The distance
between the sound sources must be less than half a wave length of the higher frequency it
must reproduce.

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The High section
The HF reproduction is assured by three 1" drivers loaded by a proprietary wave
converter with path length equalization, the ICWG, that transforms the spheric waves into
cylindrical isophasic waves coupling seamlessly with the others high frequency transducers of
the array. The ICWG output directly feed a special 90º horizontal dispersion wave guide.
1.4 BOX DESCRIPTIONAND DIMENSIONS
The NEXT LA12 (LA12C) measures only 1087mm x 395mm x 550mm (838mm x
395mm x 550mm), each enclosure includes all the required rigging hardware and fittings
needed to couple one box to another. In the drawing shown below there is a front, top and side
view of the enclosure.
Designed as a Line Array Element, the NEXT LA12 (LA12C) is intended to be used
in multi-box arrays. Due to its trapezoidal shape, these LA12 (LA12C) arrays have an
important acoustical design characteristic: no “gaps” on the front baffle. All box splay angle
adjustments are made at the rear of the enclosure, not the front. This mechanical design
allows the front baffle size and box spacing to remain relatively consistent. This results in
better overall array performance, and minimizes the diffraction that would be caused if gaps

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were opened between adjacent box edges on the front baffle of the array. A significantly
curved LA12 (LA12C) array can thus be created without gaps on the front baffle of the array.
The LA12 (LA12C) enclosure can be coupled together to create small, medium or
large arrays. The acoustic benefits of the “gapless” array characteristic become more obvious
with increasing of the array size.
1.5 OUTDOOR EXPOSURE
The LA12 (LA12C) is designed for applications that require outdoor exposure to rain,
dust and other environmental conditions. While not a fully “weatherproof” system intended
for prolonged exposure in extreme environments such as seaside or tropical locales, the
system has a number of integral features that resist environmental exposure damage. The front
and speakers protection is assured by acoustically transparent foam and a power coated metal
grille.
As with any premium-grade professional product, care should be taken with each
LA12 (LA12C) system enclosure to prevent excessive amounts of dirt, water or other foreign
substances from penetrating the interior of the box. Systems subjected to extreme
environmental conditions require a more rigorous maintenance program.
1.6 INPUT CONNECTOR PANEL
The input connector panel is located at the rear of the enclosure. It
contains printed legends on the panel to identify the system
connections. The connector panel has two paralleled Neutrik NL8
connectors. The connector pinouts are marked on the panel.

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1.7 LA12 (LA12C) LINEARRAY ELEMENT SPECIFICATIONS FOR ASINGLE
ENCLOSURE
Specification
LA12
LA12C
Type
3-way line array element
3-way compact line array element
Frequency Response (+/- 3dB)
60Hz - 19kHz
60Hz - 19kHz
Horizontal Coverage (-6dB)
90º
90º
Vertical Coverage (-6dB)
8º
8º
Components
- LF - 1 x 12" Neodymium Speaker
- MF - 2 x 6,5" Speakers
- HF - 3 x 1" Compression Drivers
- LF - 1 x 12" Neodymium Speaker
- MF - 2 x 6,5" Speakers
- HF - 3 x 1" Compression Drivers
Power Handling (AES
standard)
- LF - 700W Cont., 1600W Peak
- MF - 480W Cont., 960W Peak
- HF - 180W Cont., 720W Peak
- LF - 700W Cont., 1600W Peak
- MF - 480W Cont., 960W Peak
- HF - 180W Cont., 720W Peak
Impedance
- LF - 8 ohms
- MF - 16 ohms
- HF - 24 ohms
- LF - 8 ohms
- MF - 16 ohms
- HF - 24 ohms
Sensitivity (1w/1m half space)
- LF - 103 dB
- MF - 106 dB
- HF - 108 dB
- LF - 100 dB
- MF - 106 dB
- HF - 108 dB
Maximum SPL (Calculated)
- LF - 129dB Cont., 135dB Peak
- MF - 129.8dB Cont., 135.8dB Peak
- HF - 130.6dB Cont., 136.6dB Peak
- LF - 126dB Cont., 132dB Peak
- MF - 129.8dB Cont., 135.8dB Peak
- HF - 130.6dB Cont., 136.6dB Peak
Crossover Frequencies
400Hz, 3000Hz (active)
400Hz, 3000Hz (active)
Connectors
2 x NL8
2 x NL8

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Rigging
Integrated, Adjustable from 0º to 8º
Integrated, Adjustable from 0º to 8º
Enclosure Material
13-ply birch plywood
13-ply birch plywood
Finish
Black semi-matt textured paint
Black semi-matt textured paint
Grille
Black powercoated perfurated steel
Black powercoated perfurated steel
Dimensions (WxHxD)
1087mm x 395mm x 550mm
838mm x 395mm x 550mm
Weight
54Kg
46Kg

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2. SYSTEM CONNECTION,
AMPLIFICATION AND
DIGITAL PROCESSING
The LA12 (LA12C) is designed to be tri-amplified. All midrange transducers as well
as all high frequency transducers are energized as a group.
NEXT recommends that amplifiers have a peak voltage capacity of double the RMS
voltage at full power in order to avoid clipping the signal. For this reason maximum
Recommended Power Levels per Transducer may exceed the AES power rating of individual
drivers.
2.1 POWERAMPLIFIER
In order to power the system we make use of NEXT’S MA SERIES amplifiers with
the following rack setup:

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1 bridged NEXT MA900 amplifier for the highs;
1 channel of the NEXT MA3200 amplifier for the mids;
1 channel of the NEXT MA3200 amplifier for the low;
1 NEXT MA3800 amplifier for the sub-lows.
This rack setup is called a “slave” rack. Each of this “slave” racks, power two LA12 (LA12C)
and two LAS 218 speaker systems. In order to process the signal, a NEXT LMS 240i digital
processor is added to the first rack of the system, intitled the “master” rack, and then the
processed signal is passed from “slave” to “slave” by an LA Rack Systems Interconnection cable
(AM002).
2.2 NEXTLMS240I DIGITAL PROCESSOR
The LMS240i Digital loudspeaker management system is designed to optimize the
performance of a wide range of NEXT loudspeakers. It is a cost effective, single-rack space,
processor with fully controllable configuration and signal processing functions. The processor
is equipped with an LCD display and buttons via which it is possible to load set-ups from
memory and to modify some of the parameters of the current set-up. The LMS240i PC-
software allows the user to configure all parameters of the controller, storing them to the
processor by means of a simple USB computer connection. Superb audio quality and noise-
free operation is achieved by carefully optimized double precision signal processing coupled
with a 40-bit internal data path ensures a dynamic range in excess of 117dB. The high
sampling rate means minimal filtering providing exceptional sonic purity.

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This digital audio controller is supplied with a software (running under Windows
95/98/NT/2000/Me/XP and VISTA) that allows the user to configure all parameters of the
controller, storing them to the processor by means of a simple USB computer connection.
The LMS240i provides the sound technician all the necessary tools for setting up the
system:
-Independent input and output delays;
-42 filters absolutely configurable;

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-Up to 48 dB/Oct 4 Crossovers;
-Dynamics control and noise gate per output;
-Included Digital Input AES/EBU or S/PDIF (32-96kHz).
The NEXT LMS240i loudspeaker management system has 2 inputs and 4 outputs,
completely configurable by the user. It has been designed to perform like:
-A complete 3 and/or 4 ways PA mono processor (global equalization, delay
unit, crossover, individual equalization, limiter / compressor and an
independent noise gate per way).
-A complete 3 ways PA mono processor with sub-bass output through Aux
send;
-2-ways stereo processor;
-2-ways stereo processor with mono sub-bass + Aux;
-4 outputs distribution system with different equalization, delay and levels;
-Stereo paragraphic equalizer;
-Stereo delay line with equalization;
-Stereo compressor/limiter.
Two 32 bits floating point DSPs (Digital Signal Processors) with 40 bits of internal
resolution are included in the LMS240i processor. They can develop up to 120 million
mathematic operations per seconds. All this calculating power is used in the signal processing
algorithms which controls all the process: input delays, global equalization, crossover filters,
individual equalization for each way, output delays, protections and dynamic control and
independent noise gate per output. All of these algorithms have been developed to provide the
best precision and the lowest round-off noise in the calculations. This way, the best sound
fidelity and transparency free of noise is achieved. The CRYSTAL AD and DA converters are
24bit with a dynamic range of 117dB. This guaranties a clean and distortion free sound with a

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negligible noise-floor level, making the LMS240i one of the processors with best technical
specifications in the market.
2.3 SPEAKER CABLE REQUIREMENTS
Speaker cables terminate at the speakers with an 8-conductor Neutrik NL-8 connector.
One cable reaches from the amplifiers rack to a single LA12 (LA12C). A short jumper cable
then connects an additional LA12 (LA12C) speaker in parallel to the first.
If you are using sub-woofers, it is usually ideal to have one cable each from the amp
rack to every subwoofer. Under heavy-use applications, jumpering sub-woofers in parallel
may reduce system performance capabilities.
The LA12 (LA12C) full-range speaker connections are labeled on the rear connector
panel. One Neutrik NL-8 connector is wired as follows:
Bandpass
NL8 connector
Low
Conductor pair 2+/2-
Mids
Conductor pair 3+/3-
Highs
Conductor pair 4+/4-

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3. RIGGING
3.1 SAFETY WARNING
The following sections detail general rigging practices appropriate to the
entertainment industry, as they would apply to the rigging of NEXT’S LA12 (LA12C)
loudspeaker systems. It is intended to familiarize the reader with standard rigging hardware
and techniques for suspending NEXT’S LA12 (LA12C) loudspeaker systems overhead. Only
persons with the knowledge of proper hardware and safe rigging techniques should attempt to
suspend any sound systems overhead. Prior to suspending any NEXT’S LA12 (LA12C)
loudspeaker systems, it is essential that the user be familiar with the rigging techniques and
special safety instructions outlines in this section. The practices and rigging techniques
recommended here are in general terms to accommodate the many variations in loudspeaker
arrays and rigging configurations. As such, the user is expressly responsible for the safety of
all NEXT’S LA12 (LA12C) loudspeaker array designs and rigging configurations as
implemented in practice.
All the general rigging material in this section is based on the best available
engineering information concerning materials, practices, use and limitations of the products,
and is believed to be accurate at the time of the original printing. Therefore, the regulations

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and requirements governing rigging hardware and practices may be superseded by local
regulations. It is the responsibility of the user to ensure that any NEXT loudspeaker system is
suspended overhead in accordance with all current federal, state and local regulations. NEXT
continually engages in testing, research and development of its loudspeaker products. As a
result, the specifications are subject to change without notice. It is the responsibility of the
user to ensure that any NEXT’S loudspeaker system is suspended overhead in accordance
with the rigging techniques and safety considerations given in this section and any manual
updating notices. All non-NEXT associated hardware items necessary to rig a complete LA12
(LA12C) array (chain hoists, building tower supports, miscellaneous mechanical components
and grids) are the responsibility of others.
3.2 FLYING LOUDSPEAKERS SAFELY
Always inspect all the rigging components and cabinets for damage before assembly.
Pay special attention to the lifting points. If you suspect that any of the components are
damaged or defective, DO NOT USE THE AFFECTED PARTS. Contact your supplier for
replacements. Ensure that all local and National regulations regarding the safety and operation
of flying equipment are understood and adhered to. Information on these regulations can
usually be obtained from Local Government Offices.
When flying a loudspeaker system always wear protective headwear, footwear and eye
protection. Do not allow inexperienced persons to handle the loudspeaker system. Installation
personnel should be trained in loudspeaker flying techniques and should be fully conversant
with this manual. Ensure that public and personnel are not allowed to pass beneath the system
during the installation process. The work area should be isolated from public access. Never
leave the system unattended during the installation process. Do not place any object, no
matter how small or light, on top of the system during the installation procedure. The object
may fall when the system is flown and is likely to cause injury.
Secondary safety steels must be installed once the system has been flown to the
operating height. Secondary steels must be fitted irrespective of requirements of the local
safety standards applicable to the territory. Do not fly the system over areas to which the
audience has access. Avoid any form of dynamic loading to the assembly.

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When de-rigging the system ensure that the same care is given to the procedure as for
the installation. Pack components carefully to prevent damage during transit.
3.3 GROUND STACKING LOUDSPEAKERS SAFELY
Statistically, many more injuries occur due to unstable ground stacked PA systems
than to improperly flown systems. There are several reasons for this fact, however the
message is clear. Always survey the supporting structure upon which a ground stack is to be
built. Always look beneath PA wings to inspect the deck support and if necessary ask for the
stage scrims and dressings to be removed to allow access. If the stage surface slopes, as it
does in some theatres, ensure that the system is prevented from sliding forward due to
vibration. This may require attaching wood battens to the stage floor. For outdoor systems,
ensure that that the system is protected from wind forces which might cause the ground stack
to become unstable. Wind forces can be huge, especially upon large systems and should never
be underestimated.
Observe meteorological forecasts, calculate the “worst case” effect upon the system
prior to erection and ensure that the system is secured appropriately.
Take care when stacking cabinets. Always employ safe lifting procedures and never
attempt to build stacks without sufficient personnel and equipment.
Never allow anyone, whether operators, artists or members of the public, to climb onto
a ground stacked PA system.
Anyone who needs to climb over 6 feet high should be fitted with suitable safely
equipment including a clip-on harness. Please refer to local Health and Safety legislation in
your territory.
Apply the same attention to all safety matters when de-stacking systems.
Be aware that safety procedures are as important in the truck and in the warehouse as
they are at the venue.

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3.4 TRAINING &EDUCATION
Correct training is fundamental to safe practice when working with loudspeaker flying
systems. We recommend that users contact local industry associations for information on
appropriate courses.
3.5 RIGGING SYSTEM OVERVIEW
The NEXT loudspeaker systems have been designed to construct acoustic line arrays.
Acoustic line arrays typically consist of independent columns of loudspeaker systems. This
simplifies the rigging system. The LA12 (LA12C) loudspeaker enclosures utilize a rigging
system that makes the construction of arrays easy, predictable and repeatable. LA12 (LA12C)
enclosures are vertically trapezoidal, taller at the front than at the back. These enclosures are
linked at the front using swing arms that have two attachment points. Concerning the rear, the
enclosures are also linked using swing arms that have multiple attachment points, so that the
vertical angle of the bottom enclosure can be adjusted.
3.6 FLYING HARDWARE
The flying hardware consists of the following components:
A flying bar from which a column of LA12 (LA12C) loudspeakers enclosures is
suspended (One flying bar per column is required);
Front and rear swing arms;
Front and rear rigging slots;