Quad ESL 2812X, ESL 2912X User guide

ESL X Series

ELECTROSTATIC LOUDSPEAKER

ESL 2812X
ESL 2912X

Scan the QR code using a smart-phone device,
for product warranty registration online.

User Manual

Important Safety Instructions

RISK OF ELECTRIC SHOCK DO

NOT OPEN

AVIS:RISQUE DE CHOC ELECTRIQUE-NE PAS OUVRIR

WARNING:SHOCK HAZARD-DO NOT OPEN

IMPORTANT SAFETY INFORMATION

Read these instructions.

Keep these instructions.

WARNING: The mains plug/appliance coupler/direct
plug-in adapter is a disconnection device; it must remain
readily operable.

CAUTION: These servicing instructions are for use by
qualified service personnel only. To reduce the risk of
electric shock, do not perform any servicing other than
that contained in the operating instructions unless you
are qualified to do so.

Please do not install this equipment in a confined or
built-in space such as a bookcase or similar unit, and keep
it well-ventilated in an open space. The ventilation
should not be impeded by covering the ventilation
openings with items such as newspapers, tablecloths,
curtains, etc.

Heed all warnings.

Follow all instructions.

Do not use this apparatus near water. Clean only with a
dry cloth.

Do not block any ventilation openings. Install in
accordance with the manufacturer’s instructions.

Do not install near any heat sources, such as radiators,
heat registers, stoves, or other apparatus (including
amplifiers) that produce heat.

Do not defeat the safety purpose of the polarised or
grounding plug. A grounding 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 to have
the obsolete outlet replaced.

Protect the power cord from being walked on or pinched,
particularly at the plugs, convenience receptacles, and
the point where it exits the apparatus.

Use only with the cart, stand, tripod, bracket,
or table specified by the manufacturer or sold
with the apparatus. When using a cart or
rack, use caution when moving the
cart/apparatus combination to avoid injury
from tip-over.

WARNING: Do not expose this apparatus to rain or
moisture to reduce the risk of fire or electric shock. The
apparatus shall not be exposed to dripping or splashing,
and ensure that objects filled with liquids, such as vases,
shall not be placed on the apparatus. No naked flame
sources, such as lighted candles, should be placed on the
apparatus.

This equipment is a Class II or
double-insulated electrical appliance. It has
been designed not to require a safety
connection to the electrical earth.

Correct disposal of this product. This marking
indicates that this product should not be
disposed of with other household waste
throughout the EU. To prevent possible
environmental or human health harm from
uncontrolled waste disposal, recycle it
responsibly to promote the sustainable reuse
of material resources. To return your used
device, please use the return and collection
systems or contact the retailer where the
product was purchased. They can take this
product for environmentally safe recycling.

Unplug this apparatus during lightning storms or when
unused for long periods.

Refer all servicing to qualified service personnel.
Servicing is required when the apparatus is damaged,
such as when a power supply cord or plug is damaged,
the liquid is spilt, objects fall into the apparatus, it is
exposed to rain or moisture, does not operate normally,
or has been dropped.

WARNING: Only use attachments/accessories specified
or provided by the manufacturer (such as the exclusive
supply adapter, battery, etc.)

Catalogs

Introduction 1

The ESL Choice 2

What’s in the Box? 3

Unpacking and Assembly 4

Positioning the Loudspeakers 5

Choosing and Preparing Loudspeaker Cable 6

Connecting Your Loudspeakers 6

Operation 6

LED Illumination 7

Final Adjustments 8

Horizontal Directivity 9

Maintenance and Service 11

Quality Assurance 14

About Your ESL Loudspeaker 15

Specifications 16

Physical Measurement 20

Introduction

Congratulations! You are now the proud owner of the very best Electrostatic loudspeakers in the world—introducing the
ESL 2812X and 2912X from QUAD Electroacoustics.

Since 1956, QUAD has been at the forefront of Electrostatic loudspeaker technology, crafting products renowned for their
unmatched accuracy and neutrality. The ESL 2812X and 2912X are not just the latest iterations of the world’s most iconic
loudspeakers; they are the pinnacle of ESL evolution.

With such unsurpassed accuracy, the ESL 2812X and 2912X have earned their place as staples in major recording studios
and a highly sought-after choice among discerning audiophiles. These speakers embody the clear, natural sound that has
become synonymous with all QUAD products, ensuring that your listening experience will be nothing short of
extraordinary. Welcome to the next generation of audio excellence!

Through a process of continued evolution, thorough observation of the original ESL design, technological implementation,
manufacturing techniques, and further enhancement by the most up-to-date materials and production processes, the new
evocations of our design philosophy achieve levels of detail, clarity, and perspective that will be a revelation and source of
continuing delight to all music lovers.

Like all previous iterations, the ESL 2812X and 2912X are doublets or dipole speakers, incorporating unique panels that
produce a spherical sound field from a point source. All naturally created sounds emanate from a point source, and the ESL
speaker concept recreates this effect more than any other speaker currently available. The ESL ‘push-pull’ design offers very
low distortion, meaning that your QUAD ESLs are probably the lowest-distortion loudspeakers ever made—and this
includes the bass region, where conventional speakers suffer from time-related delays and harmonically related distortions.

With such unsurpassed accuracy, the ESL 2812X and 2912X have earned their place as staples in major recording studios
and a highly sought-after choice among discerning audiophiles. These speakers embody the clear, natural sound that has
become synonymous with all QUAD products, ensuring that your listening experience will be nothing short of
extraordinary.

Welcome to the next generation of audio excellence!

1

The ESL Choice

Ask many of the world’s most respected music industry professionals what their speaker of choice is—the answer is
surprisingly common. The QUAD ESL opens a window on a recording, unlike any other speaker.

More hi-fi critics regard the QUAD ESL as an absolute reference for their listening than any other loudspeaker. They are
regularly praised by leading hi-fi press, listed in ’14 of the most legendary hi-fi products of all time’ by What Hi-Fi?,
lauded with multiple five-star reviews, winning ‘Golden Ears’ from ‘The Absolute Sound’ (USA) and not just ‘Product of
the Year’, but also ‘Component of the Year’ from ‘Stereophile’ (USA), a ‘Diapason d’Or’ award (France); a ‘System of the
Year’ award from Hi-Fi News Magazine; and a 'Best Product' from EISA Award.

When using the QUAD ESLs for listening at home, you can be sure that your experience will mirror that of the concert
hall. Known for their incredibly natural, transparent, and detailed sound, the ESL has a reputation for being one of the
most accurate and revealing speakers in the world, especially praised for its ability to reproduce vocals and midrange
frequencies with astonishing clarity.

You can expect superior Midrange Clarity and Transparency. The ESL produces a very smooth and coherent midrange,
where vocals, instruments, and other mid-frequency sounds sound lifelike and accurate. Voices and acoustic instruments
are presented, making them sound incredibly natural. High frequencies are very detailed but not exaggerated or harsh.
They’re smooth, airy, and refined without fatigue, enabling the ESL for immersive listening sessions.

Unlike other ‘electrostatic panel’ loudspeakers, the ESL does not have an integrated subwoofer, nor is one required. The
low end is tight and accurate. The bass is fast, clean, and seamless, as is the concert hall performance, a testament to the
ESL's lifelike performance.

The QUAD ESL excels in creating a wide, open, and three-dimensional soundstage. The sound feels like it extends well
beyond the physical boundaries of the speaker, creating a sense of space and depth in the music. The placement of
instruments and voices in specific locations within the soundstage is unparalleled.

The proprietary electrostatic design of the QUAD ESL allows it to have an incredibly fast transient response, capturing the
fast attacks of percussive sounds with great accuracy. The precision in the delivery of details allows the listener to pick up
on subtle nuances in the music that would remain unheard with traditional moving coil loudspeakers.

The overall balanced presentation is breathtakingly accurate. The QUAD ESL is unmatched.

2

What’s in the Box?

The packing contains the following items:

・  The QUAD ESL loudspeaker

・  AC power lead 3m with a mains connector suitable for your region

・  This Owner's Manual

・  A set of four spiked feet

・  A set of four standard feet

・  Four clamping collars

・  One collar locking bar

・  Base stabiliser weight

・  Two securing brackets, screws and shake-proof washers

・  Two pairs of cotton gloves

Consult the dealer from whom you purchased the equipment if any of these items are not present.

Please retain the packing materials for future use or return them to your dealer. If you decide not to keep the packing,
please dispose of it sensibly. The timber, paper and plastic components are recoverable and may be taken to an
appropriate recovery service.

Please retain the owner's manual and the information concerning the date and place of purchase of this equipment for
future reference. In the unlikely event that you pass this product on to a third party, please include all the accessories
and this owner's manual.

3

Unpacking and Assembly

These loudspeakers are heavy! It needs two people to lift and manoeuvre the loudspeakers into position.

Caution: DO NOT USE THE TENSIONING BRACE TO LIFT OR MANOEUVER THE ESL, OR YOU WILL DAMAGE THE
LOUDSPEAKER. WHEN MOVING THE LOUDSPEAKER, HOLD IT BY THE SIDES OR THE SIDES AND BASE.

Always use the supplied cotton gloves when handling exposed surfaces.

Before you unpack the loudspeakers, ensure that you have a large and clear floor area on which to work. Remove or protect
any fragile carpets, etc., to avoid any damage.

Each ESL loudspeaker is packed in an outer cardboard carton and then on a pallet for safe transportation. The carton has
a lidded top and a tabbed seam down one long edge, which is taped over.

Place the speaker upright on its wooden pallet. Open the top first, then the tabbed seam all the way down. Remove the top
packing insert and the box containing the accessories. Remove the side packing pieces. The loudspeaker may now be lifted
out of the base packing.

The stabiliser block is strapped to one of the side packing pieces. Cut the ties and remove the block.

Caution: The block is heavy - exercise care.

The ESLs are provided with both spiked and standard feet, which screw
into the threaded holes in the baseplate. The heights of individual feet can
be adjusted to ensure that the loudspeaker sits securely and level on the
floor. Determine whether you will be using the spiked or the standard feet.
Remember that spiked feet are only suitable for use with carpets as they will
damage wood and stone floors. When using spikes, take care to avoid the
sharp tips.

Gently lay the loudspeaker on its front. If the floor surface is hard, place a soft cloth under the speaker first, such as a towel.
Spin one collar onto each foot all the way down, but do not tighten.

Attaching the front feet: Insert the two front feet in the threaded inserts on the base and thread them fully, but only
hand-tighten them at this stage. Refer to Illustration A below.

Attaching the stabiliser and rear feet: It is essential that you attach the stabiliser as this is both a safety and operational
feature. (As an alternative, the speaker may be attached to the floor - see Page 7)

First, attach the two clamps to the block using the provided screws and shake-proof washers. Line up the assembly with
the mounting holes in the base. Insert the feet through the support brackets and thread them into the base. Ensure that the
feet protrude below the clamps by an equal distance. When the speaker is operational, the weight/clamp assembly should
be clear of the floor surface. Tighten both rear feet. Insert the collar locking bar into a hole in the clamping ring and tighten.
Progressively move the bar from hole to hole until the feet are fully locked in place. Refer to Illustration B below.

Insert bar and tighten
clamping ring clockwise.

A

Attach the stabiliser
and rear feet.

B

4

Positioning the Loudspeakers

However good the loudspeaker is, the final results will depend on the acoustic characteristics of the listening room and the
position of the loudspeakers in it. Do not be afraid to experiment with both position and orientation and make a point of
trying some of the less obvious as well as the more obvious positions. The benefits obtained from the time spent doing this
can be very rewarding. The subject of room acoustics is complex and beyond the scope of this manual. It is assumed that
the loudspeakers will be used in a room with moderate reverberation, neither too bright nor overdamped. Furnishings can
alter the acoustic characteristics of the listening room, and here, common sense is the best guide.

The loudspeakers have constant directivity over a wide angle in both horizontal and vertical planes, so the response does
not vary with the height of the listener’s ears from the floor.

When experimenting, it is preferable to use high-quality recordings, works you are familiar with in the concert hall, or
speech.

As a dipole source, the ESL loudspeaker has considerable advantages over conventional loudspeakers regarding room
placement. No energy is radiated in the diaphragm's plane, so the axial room modes are discriminated against. Usually, the
loudspeaker is placed at an angle to both horizontal room axes, which excites both sets of horizontal axial modes. However,
this excitation is 3 dB less than with a conventional source, and it discriminates entirely against the vertical axial modes.

The loudspeakers should be placed at least 60cm (2 ft) from the rear wall of the listening room and angled towards the
listener. Placing the ESLs too close to the rear walls will adversely affect their dispersion characteristics; about 1/3 of the
way down the room's length is a good starting point. Operating the loudspeakers across corners, in alcoves or behind
furniture is not advisable. Because ESLs are a homogeneous sound source, it will be found that they can be placed
considerably further apart than usual, broadening the stereo sound stage. Proximity to the side walls is not detrimental to
performance and can actually benefit the bass response. Simple geometry will show that if the ESL is placed at an angle to
the side wall, there will be no audible reflection at the listening position.

5

Choosing and Preparing Loudspeaker Cable

Specialist audio cables usually offer better performance than general-purpose 'bell' or 'zip' wires. Audio cable is polarised,
with two cores of different colours, or often, in the case of twin cable, a coloured tracer or ridge along one wire to indicate
polarity. Choose a cable of suitable diameter – a cable that is too thin will limit the dynamics of the sound and may impair
the bass response. Split the twin cores to a depth of about 25mm. Carefully strip the insulation from each end, leaving
about 7mm of bare wire. If the cable is stranded, lightly twist together any loose strands.

Connecting Your Loudspeakers

Lift the cover off the connections panel box and store it safely until you have finished connecting the speakers. The cover
is magnetic for easy removal and replacement.

Choose an equal length of twin core speaker cable for each channel, and prepare the ends as described above. Unscrew
each speaker terminal. Thread the bared end of each cable through the hole in the bottom of the terminal post. Ensure that
there are no loose strands which may touch adjacent terminals. Retighten the terminal securely.

Connect the Left loudspeaker’s positive(+) terminal to the corresponding (+) amplifier terminal. Connect the negative(-)
terminals similarly. Repeat this procedure for the Right Channel. Note that the positive(+) terminals are located on the
right.

RIGHT LEFT

Phase

If the loudspeakers' phasing is unclear, they can be easily checked by playing a mono source. The sound should appear to
emanate from a point midway between the two loudspeakers. If this is hazy and poorly defined, the connections to one of
the loudspeakers should be reversed. When correctly connected, the loudspeakers will give a precise, defined centre
sound source with more full-bodied tenor and bass registers.

Operation

The ESL loudspeaker requires an energising voltage for operation and needs to be connected to an AC power supply.
Before connecting to the AC power supply check that the voltage range marked on the base corresponds with that of the
supply.

The on/off switch has a rocker action; press the bottom to switch the ESL on and the top to switch it off. An LED next to
the on/off switch indicates that the speaker is on.

6

LED Illumination

The QUAD logo on the speaker bezel is illuminated. This function can be switched on/off according to your preference by
way of the Logo Dimmer control on the rear panel.

The LED Halo (underside) illumination can also be adjusted according to your preference. Press and hold the ‘touch
control’ button for 3 seconds, until the underside LED Halo flashes twice. This will indicate that the unit is in 'brightness
adjustment mode'. Tapping the touch controller will cycle the LED Halo illumination settings through ‘high’, ‘medium’

(Default), ‘low’ and ‘off’ options.

The unit will automatically exit 'brightness adjustment mode' after 5 seconds of inactivity.

Logo Illumination Control

On/Off Switch

Mains Input

LED Halo Control

Mains Indicator

Amplifier Requirements

The ESL loudspeaker should be used with an amplifier of an output capability of 20V - 30V RMS (40-100W into 8 Ohms).
The impedance characteristic presents no problems to an amplifier that is unconditionally stable. Protection circuits limit
the maximum input voltage to 40V and there is no benefit from using an amplifier with an output greater than 30V RMS
(100W into 8 Ohms). Amplifiers with an output capability in excess of 35V RMS (150W into 8 Ohms approx) may be used
but with caution – see Loudspeaker Protection.

If the QUAD 405/2 power amplifier is used, the amplifier voltage limiters should not be fitted.

Loudspeaker Protection

The ESL loudspeaker is fitted with a protection circuit, incorporating a special device called a multifuse, which

prevents damage from excessive programme input signals. Should the loudspeaker be severely overdriven for
any length of time, the circuit will operate and effectively reduce the drive to the loudspeaker, causing a reduction in the
volume level with some loss of quality.

If this occurs, then the volume control of the amplifier should be turned down. After a delay of a few seconds to allow the
circuit to reset, the volume can be increased, but only to a point below which the protection circuit initially functioned,
otherwise the circuit may operate again.

Persistently overdriving the loudspeaker will cause the multifuse to completely fail, necessitating its replacement by a
qualified engineer. The above conditions are unlikely to occur in normal use or with amplifiers with a power output rating
of less than 100W unless driven into distortion. Steady state signals such as pure sine waves in excess of 10V RMS should
not be fed to the loudspeaker.

When the AC power to the loudspeaker is switched off or disconnected, the signal input protection circuit operates to
prevent excessive signals being fed to the loudspeaker elements. Even so, care should be taken to ensure that the
loudspeakers are not driven for long periods (minutes) with no AC power applied.

Caution: The QUAD logo on the front grill is set to flash if the protection circuit detects abnormally high voltage on the
ESL element. If the logo light flashes please switch off for 15 minutes then play again at a lower volume if you were
previously listening at loud volume levels. If the logo flashes at normal listening levels and reoccurs after the 15 minutes
waiting time then please contact your local QUAD Distributor for further advice.

7

Final Adjustments

After you have finalised the position of the loudspeakers, you should level the speaker by adjusting the feet.

Tensioning the Speaker

This is the final adjustment. Tighten the tensioner anti-clockwise.
This pulls the tensioning rod tight and rigidifies the assembly. Do
not omit this stage, as it significantly improves performance at high
power levels. The tensioner should be periodically checked to
ensure the speaker is fully rigid, as temperature and humidity varia­tions may cause the tension to slacken slightly.

After completing all the adjustments, gently drop the connection
panel cover into place.

Mounting Alternatives

After finalising the position of the loudspeakers, for added safety and to improve the coupling with the floor still further,
the loudspeakers may be screwed to the floor.

Disconnect each loudspeaker from the mains supply and the amplifier. Mark the position of all four feet with tape or
chalk. Place a soft towel or similar item on the floor and lay the loudspeaker carefully on its front. Remove the stabilising
block. Undo the collars on the rear feet half a turn to loosen the bracket and rotate each bracket so that it is facing the rear
of the loudspeaker. Retighten the collars.

Floor Spikes on Carpet: The pointed foot should only be used with carpets. Adjust the rear feet so that the tapered section
of the spike protrudes below the bottom of the bracket. When you screw the bracket into the floor through the carpet, the
bracket will rest on the carpet, thus avoiding damage to the carpet surface.

Standard Feet: The bottom of the floor clamp should be
marginally above the bottom of the foot. Make sure the feet
rest firmly on the floor and that the bracket is not supporting
the weight of the loudspeaker.

Stand the speaker upright. Carefully manoeuvre the loudspeaker so that the feet stand on their marked location. Now
screw the clamps to the floor using suitable screws and fixings.

Check that both front feet support the speaker. Reconnect both loudspeakers to the amplifier and the mains supply.

8

Horizontal Directivity

These are actual measurements taken from our reference samples. The directivity pattern is exceptionally well maintained,
from very low frequencies to well beyond audibility. This consistent pattern ensures a smooth spatial response with no
peaks and troughs. In addition, the ESL's virtually massless diaphragms ensure near-instantaneous starting and stopping
with an almost total absence of hysteresis, providing lightning-fast transients and phenomenally accurate bass response.

QUAD ESL 2812X

9

QUAD ESL 2912X

10

Care and Cleaning

The surfaces of the speaker should be wiped occasionally with a barely damp soft cloth. The grille cloth may be cleaned
with a soft brush or a handheld vacuum cleaner. The loudspeakers are protected against the ingress of dust, etc. Periodic
servicing at two-year intervals is recommended to keep your speakers in pristine condition. Great care has been taken in
the selection of materials to ensure long-term stability under a wide range of temperatures and humidity. In
environments where the relative humidity regularly exceeds 80%, it is recommended that the listening room be air
conditioned for optimum performance.

Caution: SWITCH THE LOUDSPEAKERS OFF AND DISCONNECT THEM FROM THE MAINS BEFORE CLEANING.

Servicing

If your QUAD equipment requires servicing, return it to the dealer from whom you purchased it. For further support and
advice, please contact the regional distributor. You are strongly advised to keep the original packaging for transport or
long-term storage.

Warranty Coverage

Your loudspeakers have been constructed to the highest standards. From top grade furniture construction and finish to

carefully designed and selected acoustic components, QUAD speakers are built to provide a lifetime of sonic pleasure.
We hope you will derive many years of good service from our products.

QUAD warrants its products, subject to the following terms and conditions below, to be free from defects in materials and
workmanship.

Online Registration

Scan the QR code using a smart-phone device,
for product warranty registration online.

The three (3) year extended warranty is applicable to items purchased from Jan 1st 2021, onwards. Items purchased prior
to this date are not eligible for this extended warranty service but are subject to statutory warranty claims and all
applicable consumer rights.

To qualify for the extended 3 year warranty, you must register your product within ninety (90) calendar days from the
date of purchase. Visit https://www.quad-hifi.co.uk/warranty-registration to complete your online registration. Items
not registered online will have a Limited Warranty for one (1) year, or for the period of your country’s statutory warranty,
whichever is longer.

Warranty can only be offered to products registered with proof of purchase with date, model and details of the authorised
dealer clearly stated on the receipt/invoice. Please keep the original receipt/invoice in case it is required for a warranty
claim.

This Limited Warranty is non-transferable and is offered exclusively to the original owner.

This Limited Warranty is valid only in the original country of purchase.

11

Warranty Coverage

Repairs or replacements are provided under this warranty are the exclusive remedy of the consumer. QUAD shall not be
liable for any incidental or consequential damages for breach of any expenses or implied warranty with any product.
Except to the extent prohibited by law, this warranty is exclusive and in lieu of all other warranties whatsoever, both
expressed and implied, including but not limited to the warrant of merchantability and fitness for practical purpose.

This warranty provides benefits that are additional to and do not affect your statutory consumer rights.

This Limited Warranty offer is subject to correct information being submitted in your application. Incorrect dates or
mismatched purchase receipt dates that are outside of the warranty terms will immediately invalidate any warranty claim.

*Please check with your dealer local distributor for further information.

Exclusions

The following items are excluded from the QUAD warranty:

Normal wear and tear and cosmetic damage (including but not limited to any wear from reasonable use, environmental
deterioration or neglect)

Products on which the serial number has been removed, altered or otherwise made illegible.

Products not purchased from an authorised QUAD dealer.

Products that were not new at the time of original purchase.

Products sold ‘as is’, ‘as seen’ or ‘with faults’.

Product not purchased from an Authorised Dealer/Distributor within the region of the claim (ie parallel imports or grey
market products)

Accidental damage or faults caused by commercial use, acts of God, incorrect installation, incorrect connection, incorrect
packaging, misuse or careless operation or handling which is not in accordance with the user instructions.

Equipment that has been operated in conjunction with unsuitable, inappropriate or faulty apparatus.

Repairs, alterations or modifications carried out by parties other than QUAD or its authorised service partners.

Damage in transit that cannot be attributable to the fault of QUAD, the authorised distributor or dealer (ie. claims
otherwise covered by transit insurance.)

Faults relating to abnormal or inappropriate power supply voltage or power surges.

Faults relating to extremities in temperature, exposure to heat, water or other liquids, insects, excessive moisture, sand,
chemicals, battery leakage or any other contaminants.

Any force majeure events, including but not limited to any acts of God, fire, lightning, typhoon, storm, earthquake,
hurricane, natural disaster, tsunami, flood, war, riot, public disturbance.

Any other causes beyond the reasonable control of either QUAD and its Authorised Distributor.

Please note items purchased before 1st Jan 2021 are not eligible for the extended warranty claim.

How to Claim

To obtain warranty service please contact the authorised dealer from which you purchased this product and present the
limited warranty certificate offered upon registration of your product’s extended warranty offer.

Do not dispatch goods without the prior agreement of the dealer distributor or authorised service centre.

12

Warranty Coverage

If asked to return products for inspection and or repair, please pack carefully preferably in the original carton or packaging
affording an equal degree of protection and returned via insured, trackable courier service.

The authorised dealer or distributor will offer full return details and instructions. However, please note if unsuitable
packaging is used the warranty may be deemed void due to improper action in return.

QUAD or the authorised distributor, dealer or service centre may make a charge for the supply of new packaging for the
return of the repaired item. Please note, insurance is recommended as goods are returned at the owner’s risk. Authorised
distributors or service centres can not be held liable for loss or damage in transit. insurance and freight charges on the
return journey will be paid for by QUAD, authorised dealer, distributor or service centre if corrective work proves to be
necessary.

In the event of ‘no-fault found’ or ‘no repair necessary’, the return shipping charge will be the responsibility of the owner.

Repairs

All repairs will be carried out by the appointed distributor (or locally appointed service centre). Repairs handled or
processed without authorisation or approval of the appointed representative will be excluded from this limited warranty.

Please note, QUAD is not able to supply parts or replacement items to any other entity than the official distributor or
authorised service centre.

Other than the warranty and services set out in this warranty, to the fullest extent permitted by law, QUAD shall not be
liable to you and/or any third party or entity whatsoever for:

Any loss, damages and/or malfunction caused to any product(s) which is/are connected to any of the products

·

covered by this warranty.

Any damages, loss and liability, whether direct, indirect, incidental, consequential special, punitive or otherwise,

·

howsoever caused by, arising out of or otherwise, in relation to the installation, delivery, use, service, repair, replacement
and/or maintenance of the product;

Any damages, loss and liability under this warranty in respect of any act, omission, or negligence of any of their

·

technicians, employees, agents, representatives or independent contractors relating to the actual or purported
performance of any of the obligations under this warranty.

Service Centre Address

For technical support, servicing or product queries and information please contact either your local retailer or the
office below.

IAG Service Dept.

13/14 Glebe Road

Huntingdon

Cambridgeshire

PE29 7DL

UK

Tel: [phone]

Email: [email protected]

For information on other authorised service centres worldwide contact QUAD International, UK.

A world wide distributors list is available on the QUAD website: www.quad-hifi.co.uk

13

Q is for Quality

QUAD’s attention to detail and our quality management standards are a byword in the hi-fi industry.

The finest C-Core transformers in the audio path provide excellent linearity,
wide bandwidth and very low phase shift.

Inspecting a panel.

The delay line - the ingenious solution that gives the ESL its legendary
point-source capability.

A section of an ESL panel.

14

About Your ESL Loudspeaker

Your ESL loudspeaker consists of a vertical multiple-element or membrane line
array mounted on top of an electronic matching circuit contained within the base
structure.

In order to achieve the efficiency needed for full-range audio operation, a large
moving diaphragm is required. This is achieved using several individual elements
connected within a rigid frame. The smaller ESL 2812X features four elements, two
bass elements and two mid and high-frequency elements, whilst the ESL 2912X
features six elements with the addition of two further bass elements.

The membrane (diaphragm) in each element is a highly charged ultra light,
immensely strong plastic film, pre-stretched and fixed to an open frame. To achieve
constant-charge conditions, this membrane is coated with a specially formulated
high-resistivity coating. This membrane is one-tenth of the thickness of a human
hair and virtually massless compared to other types of loudspeakers. Again, unlike
a conventional loudspeaker, the membrane, when energised, is driven
simultaneously over its entire surface. This combination results in an extremely fast
transient response - the diaphragm responds to alternating motion without
introducing any time lag - completely unlike the sluggish, high-mass conventional
loudspeaker.

The ESL is a dipole – the sound radiates equally from both sides of the diaphragm.

The centre two panels in each loudspeaker incorporate divisions in the diaphragm.
These can be seen as concentric rings on the outer grid plates surrounding the
diaphragm. Each ring is subjected to a minuscule time delay and attenuated by its
own individual circuit, the sound spreading gradually from the centre outwards
through each successive ring. This carefully structured delay line creates a
near-perfect spherical wave front originating from an apparent point 400mm
behind the loudspeaker. In the vertical plane the elements are line arrayed, the mid
and high frequency elements being centrally sited to preserve the spherical shape.

In order to eliminate even the slightest cancellation effect caused by diaphragm
motion interacting with the speaker frame, the base is weighted at the rear with a
steel mass spaced away from the cabinet base. An adjustable strut further increases
rigidity and improves cabinet coupling. The result is a structure of immense
stability and rigidity.

The ultimate design goal of any high-fidelity loudspeaker is faithfully to preserve
the illusion of a naturally occurring sonic event. That this is fully realised by the
QUAD ESL in practice can be seen from the loudspeakers’ polar plots reproduced
on Pages 8 and 9. These loudspeakers give a truly three-dimensional sound stage
like no other.

15

Specifications

Model ESL 2812X ESL 2912X

Format

Floor standing dipole with 3° fixed tilt

Floor standing dipole with 3° fixed tilt

Type

Point Source Time Delay

Chassis Structure

Panel Elements

Maximum Output

Sensitivity

Nominal Impedance

Impedance Variation

Maximum Input

Frequency Response

Directivity Index

Distortion (100dB @ 1m)

Multiple electrostatic drive membranes

Progressive concentric rings

Heavy duty composite aluminium / steel

4

2 N / m2 at 2m on axis

1.5 mbar per volt referred to 1m

(86dB/2.83V rms equivalent)

8 Ohms

4 - 15 Ohms

Continuous input voltage (rms):

10V Programme Peak for undistorted output: 40V

Permitted peak input: 55V

37Hz - 21kHz (-6dB)

33Hz - 23kHz (useable)

See Polar Diagrams

Above 1000Hz <0.15%

Above 100Hz <0.5%

Multiple electrostatic drive membranes

Progressive concentric rings

Heavy duty composite aluminium / steel

6

2 N / m2 at 2m on axis

1.5 mbar per volt referred to 1m

(86dB/2.83V rms equivalent)

8 Ohms

4 - 20 Ohms

Continuous input voltage (rms):

10V Programme Peak for undistorted output: 40V

Permitted peak input: 55V

32Hz - 21kHz (-6dB)

28Hz - 23kHz (useable)

See Polar Diagrams

Above 1000Hz <0.15%

Above 100Hz <0.5%

Above 50Hz <1.0%

AC Input

Power Fuse

Power Consumption

Dimensions (H x W x D)

Net Weight

*The right is reserved to alter performance, specifications and appearance as required.

220 - 240V, 100-120V

100mA anti-surge, 200 - 240V

200mA anti-surge, 100 - 120V

8W

1070 x 690 x 380 (mm)

35kg

Above 50Hz <1.0%

220 - 240V, 100-120V

100mA anti-surge, 200 - 240V

200mA anti-surge, 100 - 120V

8W

1470 x 690 x 380 (mm)

44kg

16

171819

Physical Measurement

* Cabinet dimensions are in millimeters (mm).

Correct Disposal of this product. This marking indicates that this product should not be disposed of with other
household wastes throughout the EU. To prevent possible harm to the environment or human health from
uncontrolled waste disposal, recycle it responsibly to promote the sustainable reuse of material resources. To
return your used device, please use the return and collection systems or contact the retailer where the product
was purchased. They can take this product for environmentally safe recycling.

20

IAG House, 13/14 Glebe Road, Huntingdon, Cambridgeshire, PE29 7DL, UK
Tel: [phone] Email: [email protected] http://www.quad-hifi.co.uk

IAG reserves the right to alter the design and specifications without notice. All rights reserved © IAG Group Ltd.

QUAD is a member of the International Audio Group.