EAW KF364 Loudspeaker Owner’s Manual
- June 14, 2024
- EAW
Table of Contents
- KF364 Loudspeaker
- Section 1 Important Safety Precautions -Read This First
- Section 3 Overview
- Section 4 Rigging/Mounting/Suspension
- Section 5 Rigging Design
- Section 6 Amplifier Power Requirements
- Section 7 Locating the Loudspeaker
- Section 8 Signal Connections
- Section 10 Operating the Loudspeaker
- Section 11 Inspection and Maintenance
- 810049) is available from the EAW Service Department. Tips for repainting are
- Section 12 Troubleshooting
- Section 13 Contacting EAW
- Section 14 Warranty
- References
- Read User Manual Online (PDF format)
- Download This Manual (PDF format)
KF364 Loudspeaker
LOUDSPEAKER OWNER’S MANUAL
Congratulations on the purchase of your new EAW loudspeaker. You now own one
of the finest professional audio products available – the result of
exceptional engineering and meticulous craftsmanship.
This manual is intended for use with all EAW loudspeakers. As such, it
contains information that is common to different types of loudspeakers. This
includes: safety precautions; installation, set-up, and operating
instructions; troubleshooting, maintenance, and service procedures as well as
other information specific to their use. Certain information specific to
certain classes of loudspeaker, such as powered products, is so noted. Certain
loudspeakers with specialized designs have a manual that accompanies this one
with additional instructions and other information specific for their use.
Thus, both manuals apply to those loudspeakers.
Please read this manual plus any accompanying manual and follow all relevant
precautions and instructions. This should allow you to obtain the maximum
performance from your new loudspeaker.
Where there are conflicts or overlaps, the information in any accompanying
manual supersedes the information in this manual.
Section 1 Important Safety Precautions -Read This First
Read and heed all warnings and safety instructions in this Manual before using
the product.
Failure to follow all precautions can result in equipment damage, personal
injury, or death.
1.1 Important Safety Instructions for Powered Loudspeakers
The lightning flash with arrowhead symbol within an equilateral triangle is
intended to alert the user to the presence of uninsulated “dangerous voltage”
within the product’s enclosure that may be of sufficient magnitude to
constitute a risk of electric shock to persons.
The exclamation point within an equilateral triangle is intended to alert the
user of the presence of important operating and maintenance (servicing)
instructions in the literature accompanying the appliance.
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Read these instructions.
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Keep these instructions.
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Heed all warnings.
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Follow all instructions.
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Do not use this apparatus near water.
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Clean only with dry cloth.
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Do not block any ventilation openings. Install in accordance with the manufacturer’s instructions.
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Do not install near any heat sources such as radiators, heat registers, stoves, or other apparatus (including amplifiers) that produce heat.
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Do not defeat the safety purpose of the polarized or grounding-type plug. A polarized plug has two blades with one wider than the other. A grounding type plug has two blades and a third grounding prong. The wide blade or the third prong is provided for your safety. If the provided plug does not fit into your outlet, consult an electrician for replacement of the obsolete outlet.
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The power plug at the wall must remain accessible to be able to disconnect power from the apparatus.
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Protect the power cord from being walked on or pinched particularly at plugs, convenience receptacles, and the point where they exit from the apparatus.
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Only use attachments/accessories specified by the manufacturer.
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Use only with the cart, stand, tripod, bracket, or table specified by the manufacturer, or sold with the apparatus. When a cart is used, use caution when moving the cart/apparatus combination to avoid injury from tip-over.
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Unplug this apparatus during lightning storms or when unused for long periods of time.
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Refer all servicing to qualified service personnel. Servicing is required when the apparatus has been damaged in any way, such as power-supply cord or plug is damaged, liquid has been spilled or objects have fallen into the apparatus, the apparatus has been exposed to rain or moisture, does not operate normally, or has been dropped.
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This apparatus shall not be exposed to dripping or splashing, and no object filled with liquid, such as vases, shall be placed on the apparatus.
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This apparatus has been designed with Class-I construction and must be connected to a mains socket outlet with a protective earthing connection (the third grounding prong).
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This apparatus does not exceed the Class A/Class B (whichever is applicable) limits for radio noise emissions from digital apparatus as set out in the radio interference regulations of the Canadian Department of Communications.
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If the loudspeaker is exposed to changes in temperature and humidity, internal condensation may develop. If powered up with such condensation, electronic failure could result. When exposed to environmental changes, allow the loudspeaker at least 30 minutes to acclimate to a new temperature before connecting to the ac mains and operating.
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EAW loudspeakers can produce sound levels capable of causing permanent hearing damage from prolonged exposure. The higher the sound level, the less exposure needed to cause such damage. Avoid prolonged exposure to the high sound levels from the loudspeaker.
DANGER: There is danger of explosion if battery is incorrectly replaced.
Replace only with the same or equivalent type. This applies to any
loudspeakers with a battery.
WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE THIS
APPLIANCE TO RAIN OR MOISTURE. DO NOT EXPOSE THE APPARATUS TO DRIPPING OR
SPLASHING AND DO NOT PLACE OBJECTS FILLED WITH LIQUIDS, SUCH AS DRINKS, ON
THE APPARATUS.
CAUTION: This product is energized as long as it is connected to the AC
mains supply.
CAUTION: Allow at least six inches of free space all around the amplifier
heat sink for sufficient ventilation.
1.2 EC Declaration of Conformity
Eastern Acoustic Works, as the manufacturer, hereby certifies that, in their
delivered versions, all un-powered (passive) loudspeakers comply with the
provisions of the directives and standards listed below.
European Council Directive on Low Voltage, 73/23/EEC
EN 60065:2002 Audio, video, and similar electronic apparatus – safety
requirements
European Council Directive on Electromagnetic Compatibility 89/336/EEC
EN 50081-1:1992 Emissions limit for residential, commercial, and light
industrial equipment (generic standard)
EN 50082-1:1997 Immunity requirements for residential, commercial, and light
industrial equipment (generic standard)
The Technical Report/File is maintained at:
Eastern Acoustic Works
One Main Street
Whitinsville, MA USA
Tel: +1 508 234 6158
Tel: +1 800 992 5013
e-mail: design@eaw.com
Issued: 25 July 2005
NOTE: EC Declaration of Conformity for powered loudspeakers is found in
their accompanying owner’s manuals.
1.3 Rigging: Mounting/Suspension
DANGER: Mounting or overhead suspension of any heavy load can result in
serious injury and equipment damage. This work should be done by qualified
persons following safe rigging practices in accordance with all applicable
safety and construction standards. Such persons must determine the required
load ratings and design factors. They must determine the mounting or
suspension method that meets static, dynamic, shock, and any other load
requirements. All such work must be done in accordance with and in compliance
with all federal, state, and local regulations governing such work.
CAUTION: The user assumes all responsibility and liability for the proper
design, installation, and use of any rigging and mounting systems for EAW
loudspeakers.
CAUTION: Accessory items are available from EAW and from aftermarket
suppliers to facilitate suspension, wall, ceiling, or other rigging. When
using these items, review all enclosed documentation and carefully follow all
instructions and safety precautions.
1.4 Purchaser and User Responsibility
It is the responsibility of the purchaser and end-user of EAW products to:
- Read the product instructions and labels and follow them.
- Inspect the product immediately upon receipt as well as before and after each use.
- Receive training in the proper installation and use of the equipment. Proper training includes safety procedures, limitations of the equipment, inspection of the equipment, and risk management. If you are not competent in the use of a product, do not use it.
- Determine if the product is suitable for its intended use and that it meets all applicable standards and regulations.
- Use adequate safety precautions and back-up systems.
- Practice risk management at all times.
2.1 Shipping Damage
You should have visually inspected the outside of the shipping carton and
noted any damage on the shipping bill you signed. After unpacking, if you find
concealed damage to the loudspeaker, save the packing materials for the
carrier’s inspection, notify the carrier immediately and file a shipping
damage claim. Although EAW will help in any way possible, it is always the
responsibility of the receiving party to file any shipping damage claim. The
carrier will help prepare and file this claim.
2.2 Returning Product to EAW
If this loudspeaker must be returned to EAW, contact the EAW Service
Department for a Return Authorization. Use the original shipping carton and
packing materials. If the shipping carton is damaged, contact EAW for a new
carton at a nominal cost. EAW will not be responsible for damage caused by
inadequate packing.
All units returned must have a factory Return Authorization Number. Any units
received without a Return Authorization Number assigned and written
prominently on the outside of the carton will be refused.
Section 3 Overview
This loudspeaker is intended for professional use. The construction,
components, and hardware have been designed to provide robust, reliable
performance for its intended applications. Please ensure that you fully
understand proper installation and operation before use.
You will need to perform the following general tasks to properly put the
loudspeaker into service.
Details concerning each task are provided in this manual.
- Design and install a rigging system to support the loudspeaker in its intended location and aimed in the desired direction.
- Connect the loudspeaker to a power amplifier(s) selected to provide the output needed for the loudspeaker in the application. In the case of powered loudspeakers provide an ac mains supply as specified for the particular loudspeaker.
- Set-up and adjust system gain, signal processing, and limiting, as needed to maximize the loudspeaker’s performance.
- Provide training to operate the loudspeaker within its limits.
- Provide regular inspection and maintenance to maintain the integrity of the installation and performance of the loudspeaker system.
Section 4 Rigging/Mounting/Suspension
CAUTION: The rigging information provided herein is not all-inclusive. Rather it is intended as a guide to the work scope involved and to some of the more important issues that must be considered.
4.1 Definitions
For brevity purposes, “rigging” is used herein as a general term referring to
fixed mounting and suspension as well as the hardware used for such mounting
and suspension. It also applies to temporary and permanent installation.
4.2 Rigging Information
DANGER: If there is any question about the integrity or capability of any part
to perform its intended function when used to suspend or mount a loudspeaker,
immediately remove it from service for repair or replacement.
WARNING: Do not under any circumstances use a loudspeaker’s handles to support
the weight of the loudspeaker except for their intended use: hand carrying.
The handles are not rated to support the load of the loudspeaker for
temporary or permanent installation.
WARNING: Rigging loudspeakers is an extremely serious matter with potentially
lethal consequences should anything go wrong. It is of vital importance that
this task is done by persons qualified to do so and who have a full
understanding of all factors involved, with safety as the number one priority.
Only persons with the knowledge of and experience with proper hardware and
safe rigging techniques should attempt to suspend or mount loudspeaker
systems overhead. For all questions involving loudspeaker rigging, consult a
licensed, qualified Professional Engineer or Professional Rigger. All rigging
work must be done in accordance with and in compliance with all applicable
regulations governing such work.
4.3 Working Load Limits
To maintain the Working Load Limit (WLL) for the rigging points on EAW
loudspeakers, support each loudspeaker independently of any other. This means
do not use one loudspeaker to support another.
Most EAW loudspeakers have one or more types of rigging fittings, integral
with the enclosure. Depending on the loudspeaker, these will be suitable for
fixed mounting, suspension, or both. The WLLs for these fittings are defined
and listed on the Mechanical Drawing found on the specification sheet for the
loudspeaker. This information may also be found on a yellow sticker applied to
the flybar itself. If this is missing from the drawing, contact EAW Design or
consult EAW Resolution. The WLLs do not extend to any rigging hardware
attached to these fittings nor to the connection of that hardware to
structure.
The WLLs listed are the maximum load that should ever be applied to the
fittings under any condition. The WLL assumes a straight, tensile pull,
perpendicular to the enclosure surface where the fitting is mounted and that
the enclosure and fittings are in like-new condition.
The WLL is the Ultimate Strength (breaking or failure point) divided by the
Design Factor. The WLL does not apply to any product that has been altered
from its manufactured condition.
Exceptions:
- Where a WLL is specified in an accompanying manual for a specific loudspeaker model, that rating supersedes this section.
- Where the loudspeaker is specifically designed for suspension in touring applications.
4.4 Design Factor
The Design Factor for all WLLs is a minimum of 10:1.
Section 5 Rigging Design
5.1 Rigging Design Practices
Rigging a loudspeaker requires determining:
- The rigging methods and hardware that meet static, shock, dynamic, and any other load requirements for supporting the loudspeaker from structure.
- The design factor for and the required WLL (Working Load Limit) for this support.
EAW strongly recommends the following rigging practices:
- Documentation: Thoroughly document the design with detailed drawings and parts lists.
- Analysis: Have a qualified professional, such as a licensed Professional Engineer, review and approve the design before its implementation.
- Installation: Have a qualified professional rigger do the installation and inspection.
- Safety: Use adequate safety precautions and back-up systems.
5.2 Rigging Hardware and Accessories
Rigging EAW loudspeakers will invariably require hardware not supplied by EAW.
Various types of load-rated hardware are available from a variety of third-
party sources. There are a number of such companies specializing in
manufacturing hardware for, designing, and installing rigging systems. Each
one of these tasks is a discipline in its own right. Because of the hazardous
nature of rigging work and the potential liability, engage companies that
specialize in these disciplines to do the work required.
EAW does offer certain accessory rigging items, primarily for attachment to
the hardware integral with the loudspeaker. Some items, such as eyebolts, can
be used with a variety of products. Others, particularly U-brackets and
similar hardware, can only be used with a specific product or product Series.
While these accessories are intended to facilitate installation, the wide
variety of possible installation conditions and array configurations do not
permit EAW to determine their suitability or load rating for any particular
application.
EAW is not in the business of providing complete rigging systems, either as
designers, manufacturers, or installers. It is the responsibility of the
installer to provide a properly engineered, load-certified rigging system for
supporting the loudspeaker from structure as outlined in Section 5.
Section 6 Amplifier Power Requirements
This section does not apply to powered loudspeakers.
6.1 Selecting an Amplifier
As is true of all professional loudspeaker systems, the performance of the
loudspeaker depends on an amplifier delivering an adequate supply of clean
power. Determining the appropriate power amplifier wattage for a given
loudspeaker and application is a subject of some debate within the audio
industry. As such, there is no single answer to the question of what amplifier
power you should use for a particular loudspeaker. The “Ruleof-Thumb” is an
all-purpose metric commonly used for selecting amplifier power.
A more exacting approach involves three separate and distinct issues: power
ratings, appropriate amplifier size, and preventing loudspeaker damage. These
are discussed within this section.
6.1.1 Rule-O f-Thumb For S elec ting An Amplifier
If the loudspeakers are used for professional application with competent
operators, a rule of thumb can be applied. Where the full output capabilities
of the loudspeakers may be needed to achieve appropriate acoustic output
levels, EAW recommends amplifiers with ratings up to 1.4 times the voltage,
which equals twice the wattage, listed in the loudspeaker specifications. This
provides a peak voltage capability of 6 dB above the specified rms voltage
limit. This assumes the audio signals will have a peak to average ratio in
excess of 6 dB, which is usually, but not always, true. Under this condition,
the thermal limits are unlikely to be exceeded. While this rule of thumb is
consistent with the EAW’s testing parameters, it does NOT guarantee trouble-
free operation. See Section 6.1.4 In some cases, the amplifier power
determined by the Rule-of-Thumb may not be available in acceptable products.
In this event, select an amplifier within approximately +/-25% (+/- 1 dB) of
the desired power. In some cases, particularly subwoofers or multiple LF
subsystems powered off one amplifier channel or an amplifier in bridged mode,
the desired power will exceed that available in acceptable products. In this
event, select the largest amplifier possible.
WARNING: The power amplifier sizes recommended by the above rule of thumb are
capable of continuous output levels that can cause damage to or failure of the
drivers.
Exercise caution in operation to avoid exceeding the specified, maximum rms
voltage limits. This is especially true when reproducing recorded music. Many
recordings have very low peak to average ratios such that much higher
continuous levels are possible before amplifier clipping. If an EAW Processor
or Amp is used with Greybox settings loaded, a voltage limiter will be
automatically applied.
6.1.2 Power Ratings
The voltage and/or power listed in EAW’s specifications mean that the
loudspeaker has passed EAW’s standard power-handling test. In this test, the
loudspeaker is “exercised” to a point of damage or failure. The voltage and/or
power ratings resulting from this test are intended to be used as a point of
comparison with the ratings of other loudspeakers. This rating does not
necessarily correspond to the best amplifier size to use nor is it a measure
of the “safe” amplifier size to use depending on the actual operating
conditions.
6.1.3 Selecting An Appropriate Amplifier Size
The amplifier for your loudspeaker should be sized according to both the sound
levels required and the type of audio signals that will be reproduced. This
requires a considered analysis for the particular application. If you are
unsure of how to determine these parameters, consult a qualified audio
professional or contact EAW’s Design Team.
6.1.4 Preventing Loudspeaker Damage
Preventing damage to or failure of a loudspeaker is not a function of
amplifier size nor the loudspeaker’s power rating. Preventing damage is a
function of operating an audio system so that a loudspeaker is not stressed
beyond its limits. If an audio system is operated improperly, damage to or
failure of a loudspeaker can occur even with an amplifier sized well below the
loudspeaker’s power rating. Contrarily, if an audio system is operated
properly, damage to or failure of a loudspeaker can be avoided even with an
amplifier sized well in excess of the loudspeaker’s power rating.
It is the responsibility of the audio system operator to ensure that all
equipment in the system is operated within its capabilities. This is the only
way to ensure that loudspeakers are not stressed beyond their limits to the
point of damage or failure. See Section 10.1.
Section 7 Locating the Loudspeaker
7.1 Placement Precautions for Powered Loudspeakers
7.1.1 Ambient Temperatures
If the ambient temperature is high, the amplifiers may overheat if running the
system at high output levels. In this case, aiming a fan at the heat sink to
increase the airflow past it will usually help.
7.1.2 Temperature Changes
If the loudspeaker is exposed to a rapid temperature change of more that 15° F
/ 8° C, internal condensation may develop. A good example of this is moving
the loudspeaker from outside summer conditions to an air-conditioned
environment. Allow the loudspeaker at least 30 minutes to acclimate to any
ambient temperature changes before connecting it to the ac mains and operating
it. Allow for longer acclimation times for larger temperature changes.
7.1.3 Thermal Switch
To avoid heat damage, amplifiers have a built-in, thermal switch that
activates if they overheat and puts them into a standby mode. When the
amplifiers have cooled down to a safe operating temperature, the thermal
switch will reset and the loudspeaker will resume normal operation. An
amplifier Fault indicator will illuminate if a thermal switch has been
activated.
7.1.4 Heat Sink Ventilation
The amplifiers are convection cooled by a large heat sink on the rear of the
enclosure. For efficient cooling, it is important to allow at least six inches
of free space all around the heat sink area behind the loudspeaker. Air should
be able to flow freely from below the heat sink, up around it, and then above
the enclosure.
High ambient temperatures can cause amplifiers to overheat, even when
operating well below full output. In such cases, aim a fan at the heat sink
area to increase the airflow and thus assist with cooling.
7.1.5 Stage Monitor Applications
If you use the loudspeaker on its side for stage monitor applications for
vocal monitoring, we recommended that you use at least a 12 dB per octave HPF
(High Pass Filter) on the signal, 90 Hz to 100 Hz being a good guideline. This
will allow more power for useful monitor frequencies.
Having one side of the enclosure on the floor does restrict the airflow for
cooling the amplifiers. In more extreme ambient temperatures of high level
operation, an HPF can reduce unwanted lower frequencies from being amplified.
This will reduce the overall power and thus reduce the possibility of
overheating the amplifiers.
7.1.6 Signal Levels
Keep signal levels low enough so that neither the Clip nor Limit Active
indicators are blinking frequently or are on continuously. If they are, turn
down the input signal level to avoid overheating the amplifiers.
7.2 Placement Precautions For All Loudspeakers
7.2.1 Outdoor Weather Protection
CAUTION: Do not permanently mount EAW loudspeakers in outdoor environments,
unless they are WP versions, normally special ordered. If using powered
loudspeakers temporarily outdoors, protect the loudspeaker from moisture. If
rain is expected, make sure the loudspeaker is protected by a rain cover.
7.2.2 Magnetic Fields
Loudspeakers generate magnetic fields, unless specifically designed for audio-
visual applications where drivers are magnetically shielded to limit the
extent of the magnetic field. Therefore, place a loudspeaker at least 2 ft
(0.6 m) or more from any TV set or computer monitor. If it causes distortion
or a change in the display color, move it further away. Do not place any
audio, video, or computer magnetic media near the loudspeaker as the
loudspeaker’s magnetic field may damage the data.
Section 8 Signal Connections
CAUTION: In spite of the listings below, check the input panel labeling
to verify proper connections because of possible design differences or
production changes.
8.1 Audio Input Connectors – Unpowered Loudspeakers
8.1.1 Neutrik® NL and Cannon AP® Connectors
The input connector on the loudspeaker will be one of following types with the
pin connections as listed.
NOTE: Ensure that the connection polarity is correct. To do this, connect with the “+” terminal on the loudspeaker to the like terminal on the amplifier, normally labeled: “+”, positive, or hot. Similarly connect the “-” terminal on the loudspeaker to the like terminal on the amplifier, normally labeled, “-“, negative, or ground.
8.1.2 Two Connectors
If the loudspeaker has two NL or AP type connectors, they are wired in
parallel so you can “Y-connect” multiple loudspeakers together to a single
amplifier channel. This is commonly known as “daisy chaining.” This will lower
the load impedance on the amplifier. This can be calculated by this formula:
(Nominal impedance single loudspeaker) / (number of loudspeakers daisy
chained)
8.1.3 Barrier Strip Terminal Block and Phoenix Connectors
The proper connections are marked on the loudspeaker input label, normally as
“+” and “-“.
8.1.4 Loudspeaker Wire Gauge
The proper conductor size (wire gauge) to use for the loudspeaker cable is
primarily a function of the wire length. The general rule is that lower
resistance, in relation to the loudspeaker’s impedance, is better. To achieve
this, use larger conductor sizes for longer lengths of cable and for lower
impedance loudspeaker loads.
To provide a sufficient damping factor (DF) for low frequency drivers, use loudspeaker cable with conductor sizes per the following chart. For cable lengths over 200 feet at 8 ohms, over 100 feet at 4 ohms, and over 50 ft at 2 ohms, the conductor sizes required for an adequate damping factor are rarely practical for physical and cost reasons. While it is recommended to avoid such situations the most practical wire gauge for these situations is 10 AWG / 6 mm2
Loudspeaker Cable Conductor Size
Maximum Cable Length| Nominal Loudspeaker Z| AWG Size|
Metric Size mm 2
---|---|---|---
50 ft/ 15m| 8 ohm| 14| 3.
100 ft/ 30m| 8 ohm| 12| 4
200 ft / 60m| 8 ohm| 10| 6
200 ft / > 60m| 8 ohm| Not Recommended| Not Recommended
50 ft/ 15m| 4 ohm| 12| 4
100 ft/ 30m| 4 ohm| 10| 6
100 ft/ > 30m| 4 ohm| Not Recommended| Not Recommended
50 ft/ 15m| 2 ohm| 10| 6
50 ft/> 15m| 2 ohm| Not Recommended| Not Recommended
(AWG = American Wire Gauge)
NOTE:
This table is based on achieving adequate damping factor (>20). The
associated, worstcase SPL losses are below 0.5 dB and should be considered
insignificant.
8.2 Audio Input Connections – Powered Loudspeakers
8.2.1 Input Connection
The audio input connector will be a female XLR-3 or a type of terminal block
connector. Where both male and female XLR-3 connectors are provided, the input
connection can be made to either. Normally, the female connector is used for
the input signal, with the male connector functioning as a loop through
connector for routing the audio signal to additional loudspeakers. Connect the
output from your signal source (mixing console, microphone, preamp, or other
line-level source) to the input connector on the rear panel. This is an
electronically balanced input designed to be connected to a balanced signal
source, but may be connected to an unbalanced source. However, this WILL
create a ground loop, possibly causing excessive noise. See Section 8.3.
Pin | Connection |
---|---|
1 | Sheild |
2 | signal plus or cold |
3 | signal minus or hot |
Typical XLR-3 Input and Loop Through Connectors
Terminal Block Connections:
The proper terminal block connector connections are labeled on the
loudspeaker, normally as “+”, “-“, and a shield (ground) symbol, as shown.
8.2.2 Loop or Thru Connector:
Use this connector to “daisy-chain” the input signal to multiple loudspeakers.
For terminal block connections, use multiple wires to each terminal for daisy-
chaining.
If the signal processing, including the crossover, is built in, full-range
loudspeakers and subwoofers may be daisy-chained together from a single
signalsource.
8.3 Unbalanced Connections
Connection to an unbalanced signal source will create a ground loop that can
result in excessive noise (hum and buzz) in the system. The cause of ground
loop noise can be difficult to determine, as sometimes it can even be related
to the internal design of some equipment.
For unbalanced-to-balanced connection, use an interconnect cable wired as
shown above.
The important point is that the shield and the negative signal wire from the
powered loudspeaker input are connected at the unbalanced output and usually
left “floating” at the balanced input. This wiring scheme does not prevent a
ground loop; it is simply the best way to directly wire the interconnection.
The usual way to eliminate ground loop noise is by inserting an isolation
transformer into the signal path.
WARNING: Do not defeat any safety grounding connection to the ac mains
supply to reduce ground loop noise. This is a dangerous and, in many locales,
an illegal practice.
Failure to follow this warning may result in injury or death.
8.3.1 Input Cable
For line level signals, use cable constructed with a shielded, twisted pair.
However, the requirements for portable cables and permanently installed cables
are quite different.
These will depend on the specific application, meaning the environments to
which the cable will be exposed: mechanical, chemical (atmospheric), and/or
electrical. These conditions will primarily affect the insulation and the
cable construction. For both types of applications, follow all local
electrical codes.
Section 9
Signal Processing
9.1 Digital Signal Processor Compatibility
The processing EAW determines for its loudspeakers is used to modify
performance characteristics that are stable over time and under use. For this
reason, precision in the frequency, amplitude, and phase of the settings are
critical for reproducing EAW’s settings and to maintaining those settings
over time. The only type of readily available equipment that can provide these
capabilities is a digital signal processor (DSP).
EAW signal processing settings are based on EAW’s digital processors. The
filter algorithms implemented for digital signal processing vary from
manufacturer to manufacturer. Therefore, if a different manufacturer’s digital
signal processor will be used, it is not enough to merely duplicate the
numerical settings. The transfer functions for the settings must be made
similar, meaning not only the magnitude response but also the phase response.
If the transfer functions do not match closely then this will actually
redesign the loudspeaker’s performance with arbitrary results. Contact EAW’s
Design Team for assistance about your processor’s compatibility with the EAW
factory settings.
9.2 Unpowered Loudspeakers
9.2.1 Single-amplified Mode
Signal processing, whether analog or digital, is required for all single-
amplified loudspeakers to implement the specified high-pass filter (HPF).
Digital signal processing is highly recommended as it can provide not only the
required high pass filter, but also better equalization tools, signal delay,
limiting, and accurate gain settings. With most DSP units, the settings can be
protected from unauthorized changes.
Digital Signal Processing:
For certain single-amplified products, DSP is required to achieve the designed
performance. This is stated on their specification sheets. In most cases, this
design approach was chosen to reduce the complexity of the internal passive
components, minimize power losses, and provide far more sophisticated
processing to maximize performance. The information in Section 9.2.2 applies
to such loudspeakers.
DSP Output Gains:
EAW’s published processor output gain settings are determined so as to achieve
the following conditions. This also applies to gain settings for loudspeakers
where the only processing specified is an HPF (High Pass Filter).
Unprocessed Input Signal: EIA-426B spectrum with an average level of 0 dBu /
0.775 V
Processed Output Signal: average level of 0 dBu / 0.775 V
Amplifier Gain Settings:
The amplifier gain setting for a single-amplified loudspeaker has no bearing
on the loudspeaker’s inherent performance. Choose the amplifier gain as needed
for optimum system dynamic range or as needed for a desired level relative to
any other loudspeakers in the system.
9.2.2 Multi-amplified Mode
Signal processing in the form of a digital signal processor (DSP), is required
for all multiamplified products.
Factory Signal Processing Settings:
The signal processing settings determined by EAW should be fully implemented
“as is.” They will normally provide excellent results in a variety of venues.
These settings are determined from careful laboratory measurements and affect
many aspects of the loudspeaker’s performance.
DSP Output Gains:
EAW’s output gain settings are determined so as to achieve this condition.
Unprocessed Input Signal: EIA-426B spectrum with an average level of 0 dBu /
0.775 V Processed Output Signal: Average level of 0 dBu / 0.775 V for the
least sensitive passband.
WARNING: Do not under any circumstances use “generic” or your “favorite”
crossover, output equalization, or other settings. Arbitrary settings will
actually redesign the loudspeaker’s performance with the results being equally
arbitrary. Always use EAW’s recommended signal processing settings.
Performance, in terms of frequency response, beamwidth consistency, output
level capability, and wavefront coherency is dependent on the EAW-engineered
crossover and other processing settings.
Amplifier Gain Settings – IMPORTANT:
In order for EAW signal processing to function properly for multi-amplified
loudspeakers, it is critical that all amplifiers for all passbands be set to
the same voltage gain, regardless of the amplifiers’ power output ratings.
NOTE: The same gain does NOT mean the same input sensitivity, but the
same input to output voltage gain. Consult your amplifier manufacturer if this
cannot be readily determined. Do not selectively boost or attenuate
loudspeaker levels of the amplifiers in order to balance a system. This
should be done at the output of the signal processor.
The specific gain setting chosen for the amplifiers has no bearing on the
loudspeaker’s inherent performance. Choose a gain setting as needed for
optimum system dynamic range or as needed for a desired level relative to any
other loudspeakers in the system.
9.3 Subwoofer Signal Processing
For subwoofers, a digital signal processor (DSP) is the best method for
providing crossover, output equalization, protective high pass filter, and
limiting. See Section 9.2.1 for signal processing details. These apply equally
to any quantity of subwoofer amplifier channels.
9.4 Unpowered Loudspeakers – Limiters
CAUTION: The assumptions that must be made about how to set a limiter and
what a driver’s power handling limits are cannot address all conditions of
use. As such, limiters cannot provide absolute protection nor provide any
guarantee against damage or failure from excessive inputs. At best, they can
only provide some degree of protection.
9.4.1 Limiters And Limiting
Limiters can help avoid either of two things, depending on the signal
frequency content and the amplifier / driver power ratings. The choice depends
on which will be exceeded first.
Exceeding a Loudspeaker’s Thermal Limit:
The limiter is used to prevent the amplifier, operating within its
capabilities, from exceeding the loudspeaker’s capabilities.
Exceeding the Amplifier’s Output Limit (Clipping).
The limiter is used to prevent the amplifier from exceeding its capabilities,
even though the loudspeaker is operating within its capabilities.
9.4.2 Limiter Design
EAW has done the work of determining limiter characteristics with real audio
signals by performing a number of tests on its behavior with real audio
signals and analyzing how this relates to both loudspeaker power handling
limits and sonic performance. Based on measurement and analysis of the above
variables, EAW Engineering was able to formulate a set of “rules” for setting
limiters. Listening tests determined settings that maintain good sound quality
while maximizing protection.
Because limiters differ in their behaviors from manufacturer to manufacturer,
EAW can only provide limiter settings for its own processors. These are the
only ones on which the required analysis was done to optimize settings. As
such, EAW limiter thresholds are only valid for use with an EAW digital
processor and with amplifiers that have or are set to 32 dB gain for all
passbands. This assumes that the factory gain settings for the processor
outputs are also used. For amplifiers with gain other than 32 dB and for
loudspeakers where no factory limiter settings exist, use the EAW Limiter
Wizard to determine the correct limiter threshold settings. See Section 9.4.3.
9.5 Powered Loudspeakers
9.5.1 Ex ternal Processing
Powered loudspeakers have built-in, factory set, signal processing. The
settings were determined to provide the maximum performance in terms of
frequency response, phase response, power handling, and audio quality. In some
cases, acoustical conditions, program material, or personal taste may require
additional equalization or signal processing, such as signal delay. In such
cases, use external analog or digital equalizers or other signal processing.
Avoid radical or extreme equalizer settings.
9.5.2 Limiters
Powered loudspeakers have built-in, factory set limiting. The limiter
characteristics and settings were determined to provide the maximum protection
possible, to minimize the sonic effects, and to integrate closely with the
amplifier capabilities. Defeating such limiting and/or using an external
limiter could expose the drivers or amplifiers to operation beyond their
limits.
External limiting should only be used to limit the maximum output to some
level below that allowed by the factory limiting. In this case, choose limiter
settings that minimize the sonic effects when the limiting is active.
Section 10 Operating the Loudspeaker
10.1 Operating Limits
10.1.1 Operator Responsibility – Preventing Damage
It is the responsibility of the audio system operator to operate the
loudspeaker within its limits and capabilities. This is the only way to ensure
that the loudspeaker is not stressed beyond its limits to the point of damage
or failure.
10.1.2 Loudspeaker Limits – Preventing Damage
Operation beyond the loudspeaker’s capabilities usually includes, but is not
limited to, one or more of the following conditions:
- Amplifier clipping
- Voltage input in excess of the specified rms voltage limit
- Peak voltage input in excess of twice the specified voltage limit
- Noticeable distortion
- Mechanical noise (such as a cone bottoming out)
- A suitable means for determining these conditions is highly recommended. At a minimum, the operator should have a meter display calibrated to indicate when the loudspeaker’s maximum rms voltage limits will be exceeded. This assumes amplifiers are not being driven into clipping at these limits.
10.2 Acoustic Level Precautions
CAUTION: If exposure to levels higher than 100 dB will be prolonged, wear
earplugs in the ear canals or ear protectors over the ears.
10.2.1 Operating Levels
EAW loudspeakers, when appropriately powered, are capable of producing sound
levels that are potentially damaging to your hearing. For a single loudspeaker
and depending on the product, this can easily occur within 50 ft / 15 m of the
loudspeaker. When used in multiples, such levels can be reached at
considerable distances from the loudspeakers. Avoid operating the loudspeaker
systems at levels that exceed 100 dB PL in the listening area for more than
short periods. One way to do this for musical performances is to provide some
moderate boost at the very low and to a lesser extent, at the very high
frequencies. Judicious applications of this type of equalization can make a
loudspeaker sound significantly louder than it actually is. Both your
listeners and your loudspeakers will thank you. It is recommended that a sound
level meter be used to verify listening levels. Relatively inexpensive meters
are available that provide adequate accuracy for this purpose.
Be aware that audience members will not have the benefit of ear protection.
Therefore, if you need to use ear protection because the levels are loud, the
audience also needs ear protection. The remedy is to reduce the system volume
to a safer listening level.
10.3 Testing and Test Signals
Loudspeakers are designed to reproduce primarily speech and music audio
signals. Such signals are highly variable from moment to moment in their
level, frequency content, and phase. Accepted loudspeaker measurements and
tests that are accurate and consistent are possible only with signals where
the level, frequency content, and phase are accurately known and consistent at
all times. Such signals include sine waves, swept tones, pink noise, white
noise, and other constant level test signals. These are much harder on a
loudspeaker than speech and music signals and therefore the potential for
damage is much greater. Keep in mind that the parameters of electronic
limiters are also designed for the characteristics of speech and music
signals – not test signals. Their capability to protect the loudspeaker is
considerably reduced using test signals.
Take certain precautions to avoid loudspeaker damage when using test signals.
Never use power inputs that exceed 50% (-3 dB) of the loudspeaker’s power
rating and do not test at this level for more than a few moments. For sine
waves and for any other test signals that must be used for extended periods
of time, the input to the loudspeaker should be kept below 10% (-10 dB) of the
loudspeaker’s power rating.
10.4 Measurements
The Smarts Live™ computer program, from Rational Acoustics, is an ideal tool
to use to measure and optimize a loudspeaker system or loudspeaker array for a
particular venue. This is a fast, yet sophisticated, process that will
indicate problem areas due to particular venue characteristics. Usually it is
a matter of applying small amounts of equalization to adjust significant
anomalies.
While there are a number of other commercially available and quite
sophisticated measurement programs, they are not specifically optimized for
measurements of loudspeakers in use, but rather for laboratory type
measurements. On the other hand SmaartLive provides the major benefits of
using a test signal, including music, for the measurements and providing
continuous, real-time data for making system adjustments.
A demo version of SmaartLive is available at
www.rationalacoustics.com.
Section 11 Inspection and Maintenance
Your EAW loudspeaker should require little to no regular attention for normal
use.
However, performing regular inspections and maintenance can ensure your
loudspeaker remains in optimum operating and cosmetic condition.
11.1 Periodic Inspec tion
DANGER: If there is any question about the integrity or capability of any part
used to rig a loudspeaker to perform its intended function, immediately remove
it from service for repair or replacement.
11.1.1 O verall Physical Inspec tion
Perform complete and thorough inspections of the loudspeaker on a routine,
periodic basis. The interval between inspections and scope of the inspections
will depend on the installation and the conditions of use. It is strongly
recommended that the interval between inspections not exceed 1 year.
Inspect for problems and abnormalities, including, but not limited to:
- Cracks or breaks in the wood
- Cracks or bends in the grille
- Loose or missing hardware
- Damaged mounting/rigging hardware and components
- Loose input connections
11.1.2 Rigging Inspection
Specifically and thoroughly inspect all rigging hardware and components used
to support the loudspeaker. Do this on a routine, periodic basis, whether
components are integral with or external to the loudspeaker or whether factory
or user-supplied. The interval between inspections and scope of the
inspections will depend on the installation and the conditions of use. The
rigging inspection interval must not exceed 1 year.
Inspect for problems and abnormalities including, but not limited to:
- Bends
- Breaks
- Broken parts
- Corrosion
- Cracks
- Cracks in welded joints
- Deformation
- Denting
- Wear
- Holes
- Loose or missing parts or fasteners
11.2 Periodic Performance Testing
Periodically perform listening tests and/or formal acoustical measurements for
proper performance. The interval between such tests will depend on the
frequency of system usage and the conditions of use.
A simple test is to play a CD through it using well-defined, articulate, wide-
range program material. Listen to ensure all drivers are working properly and
for any evidence of distortion or other extraneous sounds. Test at several
volume levels: very low, normal, and high.
All drivers should be tested for functionality and proper performance. A sine
wave sweep at approximately 10% of rated power will usually reveal driver
and/or enclosure problems in the form of distortion, buzzes, or rattles.
11.3 Periodic Maintenance
11.3.1 Periodic Acoustical Maintenance
Normally, no periodic maintenance, beyond the testing and inspections detailed
in Sections 11.1 and 11.2, is required to maintain the acoustical performance.
11.3.2 Routine Maintenance
Periodically do routine maintenance on the loudspeaker. The interval between
maintenance times and the scope of the maintenance will depend on the
installation and the conditions of use. It is strongly recommended that
maintenance intervals not exceed 1 year.
Maintenance shall include but not be limited to:
- Repair or replace of any item determined by inspection to be sub-standard for their intended use.
- Replace any load supporting parts whose load handling integrity is the least bit questionable.
- Lubricate all parts subject to friction using WD-40, Scott oil FS365, or similar. These are water-based lubricants with machine oil, surfactant, an anti-rust treatment.
- Tighten all accessible screws, nuts, and bolts, especially those that are part of the rigging hardware.
- Clean the exterior surfaces of the enclosure and rigging system as required, this largely depending on the type of “dirt”. Normally, use a cloth dampened with mild soapy water to remove dust, dirt, food spills or similar. Avoid getting moisture into any of the openings of the cabinet, particularly where the drivers are located. After cleaning, use a clean dry cloth to remove any excess moisture and treat metal parts and the rigging system with lubricant to prevent rusting.
CAUTION: For powered loudspeakers, do cleaning only when the power is
turned off.
CAUTION: To avoid damaging the exterior finishes do not use cleaning
solvents or abrasives.
11.3.3 Cosmetic Maintenance
While the paint finish and the wood used for the enclosures are of high
quality and durability, mars, marks, scratches, and other blemishes may appear
from normal handling. For cosmetically damaged wood, repair such damage using
common woodworking methods and materials as appropriate for the damage.
Scratches on the enclosure or hardware can be painted over with an outdoor
latex paint or simply colored in with a “Sharpie” or artist’s marking pen.
More serious gouges or dents should be sanded out, filled with wood putty,
and repainted. Black touch-up paint in pints (part #810050) or quarts (part
810049) is available from the EAW Service Department. Tips for repainting are
on EAW’s website.
11.3.4 Long Term Maintenance
For approximately five years, only routine inspections, performance testing,
and maintenance are normally required to maintain the loudspeaker’s
performance. Over a longer period, there are possible, additional maintenance
issues: Ferrofluid:
Some EAW loudspeaker models employ compression drivers with Ferrofluid-filled
magnetic gaps. This magnetic fluid fills the loudspeaker’s magnetic gap to
cool the driver by transferring heat from the voice coil through the fluid to
the magnet structure. Over time, the Ferrofluid can thicken enough to affect
the acoustical response and should be replaced. For normal conditions of use,
Ferrofluid will retain its original properties for 6 years or more. However,
if a loudspeaker is driven very hard on a daily basis, the Ferrofluid may
retain its properties for only 2 years.
When either of these conditions of use apply, replace the Ferrofluid to
restore performance.
Contact the EAW Service Department for instructions.
Grille Material:
Some EAW loudspeaker grilles are backed by either cloth or foam. This material
can deteriorate over time due to various environmental conditions and effects,
particularly if installed outdoors. If these conditions of use apply,
periodically inspect and replace any deteriorated grille material. Contact the
EAW Service Department for materials and instructions.
Cosmetics:
Various finishes are used on loudspeaker enclosures depending on the product
and its applications. While these finishes are designed to be durable over
long periods, like any applied finish, they can deteriorate over time, largely
depending on the conditions of use. While this deterioration will not affect
performance, refinish the loudspeaker as needed for aesthetic reasons. Contact
the EAW Service Department for instructions.
Section 12 Troubleshooting
12.1 Rigging Problems
Because of the potential serious consequences and liabilities due to faulty
rigging, contact the EAW Design Team to determine the appropriate service
solution for any problems with the rigging hardware integral to the enclosure
or EAW rigging accessories.
12.2 Enclosure and Integral Hardware
Enclosure problems, such as loose hardware, faulty joints, or other structural
problems, will usually be heard as distinct buzzes, rattles, or other unwanted
noises. To test for enclosure problems, use a sine wave signal manually swept
on the LF sub-system. The input level should be varied, because certain
problems can be level as well as frequency specific. However, in no
circumstances should the sine wave level be higher than 6 dB below rated power
(equal to no higher than 1/2 rated rms input voltage). It may be possible to
field-repair some enclosure problems.
12.3 Cosmetics
While the paint finish and the wood used for the enclosures is of high quality
and durability, mars, marks, and other blemishes may appear from normal
handling for an installation. For paint touchup, use good quality latex paint.
For a more permanent and cosmetically correct appearance, contact the EAW
Service Department for the paint specifications or to purchase small
quantities for touch-up. For cosmetically damaged wood, use common woodworking
methods and materials as appropriate for the damage.
12.4 Isolated Sonic Problems
12.4.1 What is Involved
Loudspeakers invariably consist of an input panel, internal components and
wiring, drivers, and an enclosure.
Troubleshooting for various performance problems usually involves isolating
the problem to one of these areas. In most cases, the fault can be clearly
isolated to one of them and that will determine the appropriate action for
servicing.
- Drivers
- Input panel, internal crossover/filter components, and wiring (unpowered loudspeakers)
- Internal electronics (powered loudspeakers)
- Enclosure and integral hardware
If no problems can be traced to any of these items, look for problems with
external electronics or cabling. Troubleshooting these items is beyond the
scope of this manual.
12.4.2 Drivers
A faulty driver will usually cause readily audible distortions or other
unwanted noises. In other cases, they may stop functioning. Use your ears and
test signals or other sound source to determine which one is at fault.
Normally, a faulty driver requires return for service or replacement by EAW.
12.4.3 Input Panel and Wiring
Faults with these items will usually cause a driver to stop working or be
intermittent.
For unpowered loudspeakers:
Check wiring continuity from the input jacks to the crossovers and from the
crossovers to the driver terminals. Many faults in this area can be field-
repaired.
For powered loudspeakers:
Check wiring continuity at the input jacks and from the amplifier(s) to the
driver terminals. Many faults in this area can be field-repaired.
12.4.4 Crossovers
NOTE: This section does not apply to powered loudspeakers.
Faults with these items will usually cause drivers to stop working, be
intermittent, or alter the frequency response. If a crossover fault is
suspected, the nature of the fault determines the action. A poor connection or
obviously open circuited, shorted, or physically damaged component (such as
from overheating) can be relatively easy to find and fieldrepair. An
improperly functioning component may require more sophisticated
troubleshooting, as the fault will likely be frequency dependent. A faulty
crossover is best returned for service or replacement by EAW.
12.4.5 Enclosure and Integral Hardware
Enclosure problems, such as loose hardware, faulty joints, or other structural
problems, will usually be heard as distinct buzzes, rattles, or other unwanted
noises. To test for enclosure problems, use a sine wave signal manually swept
on the LF sub-system. The input level should be varied, because certain
problems can be level as well as frequency specific. However, in no
circumstances should the sine wave level be higher than 6 dB below rated power
(equal to no higher than 1/2 rated rms voltage). It may be possible to field-
repair some enclosure problems.
12.5 Problem Symptoms
Loudspeaker difficulties usually fall into one of the following categories.
The causes for each problem are listed in the most likely order of
probability.
12.5.1 No Sound or Low Output
- Loudspeaker cables or connectors are mis-wired or faulty: Check all cabling. Refer to these instructions for correct loudspeaker cable connections. The best way to check a suspect cable is to swap it with a known good cable. Read the loudspeaker’s input panel to verify correct cable connections.
- Electronic equipment is not turned on or level controls are not adjusted properly: Make sure that all equipment in the signal path is powered up and that all controls are set to appropriate levels for normal operation.
- Loudspeaker is not working: Connect the signal cable to a known good loudspeaker leaving all equipment set to the same levels. If the problem disappears, the loudspeaker is probably not working. Contact EAW Service for appropriate troubleshooting.
12.5.2 Distorted Sound
- The power amplifier is clipping: The signal level is exceeding the limits of your system and you must reduce the level.
- Other electronic equipment is clipping: Ensure that no equipment in the signal chain is being overdriven. For example: input(s) or summing bus in the mixing console, equalizers, etc.
- Driver(s) not working properly: Contact EAW Service for appropriate troubleshooting.
12.5.3 Partial Sound (Some Frequency Bands Missing)
- Incorrect EQ settings in the electronic equipment: Ensure all EQ settings and filters on the mixing console or preamplifier and on other equipment are set for normal operation. Ensure level controls on electronic crossovers and associated amplifiers are correctly set and that all cables and connections for such equipment are working properly.
- Incorrect processor configuration: Make sure the processor configuration is correct for the loudspeaker and its intended mode of operation. This includes settings made using software for powered loudspeakers.
- For unpowered loudspeakers: Incorrect mode switch settings on the loudspeaker input panel. Ensure this switch is set for the operating mode you are using: single, bi-amplified or tri-amplified.
- For powered loudspeakers: Incorrect control switch settings on the loudspeaker input panel. Ensure switch settings are correct for the application.
- Driver(s) not working properly: Contact EAW Design for appropriate troubleshooting.
- The crossover network inside the loudspeaker is not working properly: Contact EAW Design for appropriate troubleshooting.
12.5.4 Powered Loudspeaker Electronics
Some faults with the electronics will normally be indicated by an Amplifier
Fault indicator. Others should clearly be indicated by an outright malfunction
in the sound output. Such malfunctions can include:
- No or very low sound output
- Highly distorted sound
- Bad frequency response, such as the loss of low or high frequencies
- Intermittent sound
- Excessive electronic noise
In the case of malfunctioning electronics, contact the EAW Service Department for troubleshooting and repair instructions.
Section 13 Contacting EAW
In this manual we have tried to answer any questions you may have about EAW
loudspeakers. Should you need further assistance, please do not hesitate to
contact us.
You can contact us in several different ways.
13.1 Operating Questions
For questions about configuring, operating or troubleshooting the loudspeaker,
contact: EAW Design
Tel: | 508 234 6158 |
---|---|
Tel: | 800 992 5013 |
e-mail: | design@eaw.com |
13.2 Service Information
For questions about servicing the loudspeaker, contact:
EAW Service Department
Shipping:| One Main Street
Whitinsville, MA 01588 USA
---|---
Tel:| 508 234 6158
Tel:| 800-992-5013
e-mail:| parts@eaw.com
13.3 General Information
For all other information:
Mail:| Eastern Acoustic Works
One Main Street
Whitinsville, MA 01588 USA
---|---
Tel:| 508 234 6158
Tel:| 800 992 5013
Web Site:| http://www.eaw.com
Section 14 Warranty
Your EAW loudspeaker is warranted against factory defects for these periods
from the date of installation:
Six (6) years for loudspeakers and drivers
Five (5) years for weather protected (WP) loudspeakers products
Two (2) years ac powered electronics
See the warranty card packaged with the product for the complete warranty
statement and warranty service details.
IMPORTANT: Retain your sales receipt as this is proof of your warranty
coverage.
Eastern Acoustic Works
One Main Street | Whitinsville, MA 01588 | USA
tel 800 992 5013 / +1 508 234 6158
www.eaw.com
©2019 Eastern Acoustic Works
All rights reserved. Products are not drawn to scale.
All terms, conditions, and specifications subject to change without notice.
References
- EAW: Eastern Acoustic Works | High-performance, professional loudspeaker system design and manufacturer
- Rational Acoustics
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