Important Safety Information - · PDF fileImportant Safety Information 1 General Care of Your System 1 Contents 3 Introduction 5 Overview of Common Features 6 ... Internally, however,

OWNERS MANUAL

Model 201/2 Model 202/2c Model 203/2 Model 204/2c Model 205/2 Model 206/2ds Model 207/2

Thank you for purchasing KEF Reference Seriesloudspeakers. These have been designed tofaithfully reproduce high quality sound over manyyears of use and should provide realisticreproduction of music and speech. Please take alittle time to read these instructions prior to use.

Your KEF Reference Loudspeakers are tall,slim and extremely heavy. Installed correctly ona smooth, level surface, your loudspeakersshould be entirely safe to listen to and tolive with.

However, if you have small children, large pets,the infirm, uneven flooring or unusually thickcarpeting in your home, then correct adjustmentof the foot assemblies is imperative, if safe,stable operation is to be achieved.

Warning: The metal tweeter dome now hasprotective mesh at the centre of the Uni-Q®

driver array; if however this is compromised andthe dome itself is dented, it will permanentlyimpair performance.

1. Avoid temperature extremes.

2. Avoid damp.

3. Avoid direct sunlight.

4. Clean with the KEF cloth provided.

5. Do not use spirit based cleaners.

If you are at all uncertain about setting up, operating or caring for your systemyour dealer will be pleased to assist you.

1. Read this manual carefully, especially thesafety information, before attempting toassemble and operate the system.

2. Follow the unpacking and assemblyinstructions on the cartons. Please note thatlifting the heavier Model 207/2 and Model204/2c requires two able-bodied persons.

3. Never connect the system directly to theelectricity supply.

4. Trailing cables are dangerous. Ensure allcables are secure and tidy.

5. When stripping cables use only toolsdesigned specifically for the purpose ie:correct wire cutters or cable strippers. Do not attempt to strip cables with a knife asthis could result in serious injury.

Important Safety Information

General Care of your System

1 Part No.: 290201EIssue 2: January 2007

2 3

Important Safety Information 1

General Care of Your System 1

Contents 3

Introduction 5

Overview of Common Features 6

Model 207/2 7

Model 205/2 7

Model 203/2 7

Model 201/2 8

Model 206/2ds 8

Model 202/2c 8

Model 204/2c 8

Installation and Operation 9

Unpacking, Handling and Aftercare 9

Adjusting the Feet and/or Spikes 10

Loudspeaker Placement and Room Acoustics 11

Loudspeaker Positioning 12

Amplifier to Loudspeaker Connections 14

Amplifier Requirements and Power Handling 14

Uni Balance Adjustment Models 201/2, 203/2, 205/2, 207/2, 206/2ds 15

Placement Adjustment Models 202/2c, 204/2c 17

Single, Bi and Tri-wire Connections 18

Loudspeaker Cables 23

Grilles 23

Warranty 23

Service Information 23

Specifications 24

KEF Heritage 29

Wrong

Adjustment

Caution/Warning

Positive/RED

Negative/BLACK

Switch off appliance

Option

Correct

Contents

5

Since its formation in 1961, KEF has pioneeredmany innovations in loudspeaker technology anddesign. Your new Reference Series loudspeakerscontain one of the latest of these advances -the KEF ‘Project Austin’ Uni-Q driver array.

In this innovative KEF design, not only are themid and high-frequency drivers on the same axis(co-axial), but their acoustic centres are also onthe same plane (co-planar). The profile of themid-frequency driver’s cone modifies thedirectivity factor (or ‘Q’) of the high frequencyunit such that both drive units have the samedirectivity in the critical crossover region,where they are operating at similar frequencies.This unification of the ‘Q’ of the drive units liesbehind the name “Uni-Q”.

Now incorporated in many KEF loudspeakers,the Uni-Q driver array yields immediate andreadily audible sonic benefits. With no sharpdiscontinuity in ‘Q’ at the crossover frequency,correct tonal balance is not confined to asingle ‘sweet spot’ in the listening room andis extended to cover a far broader area.With sound arriving in phase, the sound sourceis brought into the sharpest possible focus.With properly recorded material and as part ofa good quality system, well set-up, loudspeakerswith KEF Uni-Q can reveal the location of eachmusical voice in the stereo image with pin-pointaccuracy and with a much smoother responsebeing maintained off-axis - where most peoplelisten - than before.

The latest Uni-Q array implemented in thisrange is a sophisticated device offering acombination of wider bandwidth and widerdispersion than its predecessor.

Both the midrange and high frequency drivershave been symbiotically designed to take us onestep closer to the ideal of a controlled directivitypoint source acoustic radiating system.The 165mm (6.5in.) midrange section has ashallow ‘Uni-Form’ cone profile which givesexcellent midrange performance but alsoprovides the optimum waveguide for thecoincidentally mounted tweeter.

This new two piece 25mm (1in.) titanium dometweeter has been developed utilising FiniteElements Analysis techniques to provide‘pistonic’ motion to a much higher frequency,eliminating the need for a separatehyper-tweeter.

It also features a vented pole piece,increasing the air space behind the domeproviding an extended but smooth highfrequency performance whilst retaining ultrawide bandwidth source compatibility:DVD-A/SACD.

Introduction

6 7

Four drive units in a three-way configuration areemployed in the Model 205/2. The single Uni-Qdriver array for upper mid-range and highfrequencies with ultrasonic extension, and a pairof 200mm (8in.) drive units in IDL configurationfor low frequencies. This system works optimallyin medium to large rooms where its controlledand extended bass lays a strong foundation tothe superior imaging of the Uni-Q driver array.

Model 203/2 is a floorstanding three-wayloudspeaker with four drive units designed forhigh quality reproduction in medium sized roomsor where space is limited. Two 165mm (6.5in.)drive units in IDL configuration handle bassfrequencies, the mid-range and high frequenciesare handled by the Uni-Q driver arrayextending the response smoothly into theultrasonic region.

Model 205/2 Model 203/2

Model 207/2

The KEF Reference Series products covered bythis manual are loudspeakers designed primarilyto operate away from room boundaries(free space), where the renowned stereoimaging of the Uni-Q driver array is at its best.However, a bass level adjustment is provided(Uni Balance) on all Reference Series Modelswhich corrects the response to allow forplacement close to a wall.

In addition, all the models listed featurea four step independent HF adjustment(also accessed via the Uni Balance terminals) toallow further tailoring to a particular acousticenvironment or to allow for the presentationof accompanying electronics.

All models use Reference matched drive unitsand crossovers that have been manufactured tolaboratory-standards and rigorously tested atevery stage of production. The drivercomplement of each system reflects theincreasing performance capabilities of eachmodel, particularly its ability to reproduce widerbandwidth at higher output levels.

Independent Driver Loading (IDL) is utilised forthe bass sections of this new Reference Range.Using two identical bass units rather than a single larger one has the advantage ofmaintaining a slim profile for the cabinet andsubsequently wide and even sound dispersion. Internally, however, a tall slim enclosure suffersfrom strong top-to-bottom acoustic standingwaves which are very difficult to control.

IDL divides the enclosure into two half-heightenclosures, one for each bass driver, with muchimproved internal acoustics.

Thanks to their internal Magnetic Shielding,these loudspeakers may be used close-to orbeside a television set or video monitor,when used in front left and right channelpositions in Home Theatre or SurroundSound applications.

The centre loudspeakers also include abass adjustment for TV or wall mounting,plus a high frequency boost facility for whenthey need to be mounted behind an acousticallytransparent screen.

All models are timbre matched to each other socombining different models in an AV system is noproblem. Extra Reference loudspeakers can beadded to your system with the knowledgethat the system tonal balance and integration willbe maintained.

Wide entry, gold-plated tri-wire/tri-ampterminals are fitted to the custom-designedmoulded terminal assembly at the rear of theloudspeaker cabinet. This allows the use of themany different gauges of loudspeaker cable thatare available.

Overview of Common Features of KEF Reference

The flagship of the new KEF Referencerange, Model 207/2 is designed to faithfullyreproduce the full bandwidth anddynamics of music signals. It is a nocompromise design where acousticperformance is the prime objective.

A complex, fully fourth order, high-quality,hand-soldered dividing network and fivedrive units are utilised in the Model 207/2.

The dividing network has its cross-overpoints at 120Hz, 400Hz and 2.3kHzand smoothly directs appropriatefrequencies to the relevant drive units.The new 165mm (6.5in.) Reference SeriesUni-Q driver array is used here for uppermid, high and very high frequencies.A 250mm (10in.) lower mid-rangeunit fitted within its own individualcompartment and two 250mm (10in.)fibre reinforced pulp-cone bass units,mounted in IDL (Independent DriverLoading) configuration, complete thedriver complement.

98

These Reference Series loudspeakers arepacked one loudspeaker per carton. Prior tounpacking, please ensure that the serial numbersof the loudspeakers supplied match each other.Then, unpack the loudspeakers carefullyand inspect for any sign of damage.Your loudspeakers left KEF in perfect condition.If any damage is apparent, you should notify yourretailer or consultant immediately. Retain thepackaging in case a need arises for you totransport the loudspeakers at a later date.

You will notice that a special KEF care-pack isincluded with each pair of loudspeakers.This pack contains a cleaning cloth and all therequired accessories for connecting andpositioning your loudspeakers. The care packalso contains the unique product buildcertificate. This is a valuable document andguarantees the quality and craftsmanship ofyour loudspeakers.

The cabinets are finished in real wood veneerand should be treated with the same care withwhich you would treat fine furniture. A suitablecleaning cloth is included in the customer carepack to maintain the original finish and lustre.

It is normal for the appearance of wood veneerto change with the passing of time, but locationsin direct sunlight should, if possible, be avoided.Furthermore the cabinets should not be allowedto become wet.

Each Reference Series floorstanding loudspeakeris supplied with KEF designed substantial spikesand locking nuts (also in the care pack).This enables fine adjustment of level, dependingon your preferred location of the loudspeakerswhatever the floor covering, carpet, tile or blockwood. In addition to the spikes and locking nutseach Model 207/2 also comes with castors.

Unpacking, Handling and Aftercare

Installation and Operation

Model 202/2c Model 204/2c

Model 202/2c is a centre channel loudspeakerdesigned primarily to match the Model 201/2and Model 203/2 main loudspeakers and smallerscreens. It uses the same drive unit complementas the Model 203/2 and, like the larger Model204/2c is timbre matched to the otherReference Series loudspeakers thereby allowinga seamlessly integrated 3D soundstage to be setup in the listening room. The size has beenchosen to allow it to be mounted moreconveniently underneath the screen within thetypical dimensions of a 32in. widescreen TV orpanel stand.

Models 202/2c and 204/2c have magneticallyshielded drive units and crossover networksthus minimising any interference with CRTtype televisions.

Truly a statement centre channel loudspeaker,the Model 204/2c fully exploits the dynamicsand bandwidth of modern AV soundtracks.With around 70% of a typical soundtrack comingfrom the centre channel it makes sense tomake this loudspeaker a truly capable one.Four 165mm (6.5in.) LF units combine withthe 165mm (6.5in.) Uni-Q driver array in a threeway reflex system which, like the Model 202/2c,not only has a bass level adjustment forclose to wall mounting but also a treble boostfacility for mounting behind an acousticallytransparent screen.

Four specialised rubber feet or bumpers arefirmly fixed to the base during production tomake sitting easier straight from the box.In addition, dedicated stands are available forthe Model 202/2c and Model 204/2c centreloudspeakers which allows them to besecurely mounted for optimum performance infree space.

OWNERS MANUAL

Model 201/2Model 202/2

Model 203/2Model 204/2

Model 205/2Model 206/2d

Model 207/2

Model 201/2 Model 206/2ds

This is a three-way loudspeaker designedprimarily for high quality reproduction as a mainloudspeaker in small rooms or as a high qualitysatellite loudspeaker in AV systems where spaceis at a premium. Model 201/2 has three driveunits, two of which are combined in the single165mm (6.5in.) Uni-Q driver array, with a165mm (6.5in.) fibre reinforced pulp conebass unit mounted in a reflex enclosure,completing the driver line up.

The Model 206/2ds is a dedicated dipole rearsurround loudspeaker for KEF Reference multi-channel systems. Incorporating twoReference Series Uni-Q driver arrays and anadditional 200mm (8in.) ultra low distortion bassdriver, the Model 206/2ds is perfectly timbrematched with the other Reference Seriesloudspeakers.

1110

Under normal circumstances your loudspeakerswill be commissioned by your retailer orconsultant, who will have been trained in theirinstallation by KEF.

KEF strongly recommend that you donot attempt to level your loudspeakerssingle-handed.

Recruit the assistance of another adult -or consult an authorised KEF Reference outletfor assistance which may be chargeable if thepurchase was not made through them originally.

The spike/locking nut combination supplied isdesigned to provide small adjustments, not tocompensate for seriously irregular floors.A spirit level is provided with certain models togauge when the loudspeaker is perfectly level.

A rigidly-sited loudspeaker performs better thanone that can move because it enables the cabinetto remain fixed while the drive units are allowedto move as determined by the source signal.

Best results will be obtained if the loudspeakersare level and stable. Check the general stabilityof each loudspeaker by gently rocking it fromside to side, front-to-back and diagonally.Often, you will find that the loudspeaker is closeto vertical, but rocks because one spike (or twospikes diagonally) seems too short.

If the general stability is good, but theloudspeaker is leaning to left, right, backward orforward, then equal minor adjustments to thetwo spikes opposite to the direction of leanshould be made.

Adjusting the Feet and/or Spikes

* Only supplied withModel 207/2

*

The listening room is one of the most variableelements in the hi-fi chain and its effect cannotbe emphasised too strongly, nor can its effects bereliably predicted. Spacing the loudspeakersapproximately 2m - 3m (6ft. - 10ft.) apart willallow the stereo images to develop fully.You should sit at a distance at least equal to andpreferably greater than the distance betweenthe loudspeakers.

Positioning the loudspeaker in a corner or nearto a side wall is not recommended as thesignificant bass boost caused by this position willaffect the sound and cause the stereo image todeteriorate. However, placement close to thefront wall is catered for in the Uni Balancefeature (see later). It is best to place theloudspeakers symmetrically within the room,

relative to the walls, ceiling and floor,where possible.

Be aware also that soft furnishings near to aloudspeaker will deaden the sound - similarly,nearby reflective surfaces may brighten up thesound. Move the loudspeakers until you aresatisfied that the sound is right and that thestereo image is well defined.

Like all other KEF Uni-Q loudspeakers,your Reference Series loudspeakers aredesigned to be used with little or no ‘toe-in’.However if required a ‘brighter’, or ‘sharper’sound may be obtained by pointing theloudspeakers directly towards the listeningposition or adjusting the HF output(via Uni Balance).

Loudspeaker Placement and Room Acoustics

min.

min.

1312

2m(6' 8")

2m(6' 8")

Loudspeaker Positioning

14 15

All connections should be made with theamplifier switched OFF. Ensure the integrity of allconnections prior to switching the amplifier ON.

KEF Reference Series loudspeakers arefitted with purpose designed gold-platedTri-wire/Tri-amp terminals which will acceptbare wire, spade or 4mm connectors.

Most good quality loudspeaker cables have someindication, such as colour coding or ‘ribbing’on the insulating material, indicating whichconductor is ‘+’ or positive. Connection to theloudspeakers can then be made as follows:

The left channel amplifier output terminalmarked ‘+’ or coloured RED connects to the leftloudspeaker terminal marked ‘+’. The leftchannel amplifier output terminal marked ‘-’ orcoloured BLACK connects to the leftloudspeaker terminal marked ‘-’. Similarly,these instructions should be followed formaking connections between the right channelamplifier output and the right loudspeaker.Correct polarity, or phase, is vital to the properoperation of the system.

If the connections are not made correctly thesound will deteriorate giving poor bass outputand a diffuse presentation of the soundstage.

Bare wire connections are the simplest toachieve and involve stripping 12.5mm (1.2in.) ofinsulation to expose the loudspeaker wire core.(You should twist together, using clean fingers,the ends of each multi-stranded core prior tothe next stage to ensure a good signal contact).Having unscrewed the lower terminal cap,push the wire through the exposed hole in theterminal body and screw the cap down tightly.

Make sure that no stray strands come intocontact with the opposite terminal; this couldcause a short circuit between the terminals andmay damage your amplifier.

Be aware that a higher quality run of cable willalways give a more rewarding presentation thanmultiple runs of an inferior cable.

Amplifier to Loudspeaker Connections

Models 201/2, 203/2, 205/2, 207/2 and 206/2dsincorporate separate adjustments for bass andtreble output situated at the top of the terminalpanel (see below). The left hand terminalallows a two position bass level adjustmentwhile the centre and right hand terminals

allow a four position tweeter level setting.Three gold plated screw caps are supplied witheach loudspeaker, one for the LF and two for theHF adjustment.

LF Adjustment

With the supplied cap screwed into the‘LF Adjust’ terminal the bass level is set at the‘flat’ setting - for free space positioning. When aloudspeaker is positioned close to a wall the perceived bass level is increased byapproximately 2dB.

If the cap is removed from the LF Adjustterminal the bass level is reduced to correctthe loudspeaker response for the proximity ofthe wall.

Uni Balance Adjustment

2. Cutcap out

1. Flatcap in

1

2

Level (dB)

Frequency

300 Hz150 Hz50 Hz

-2.0

0.0 ModeLF

level (dB)

1. cap in 0.0

2. cap out -2.0

In KEF literature and in the specificationtable within these instructions are listeda range of amplifier power outputs to matchyour Reference Series loudspeakers.Conditions of use (room size, type ofprogramme, preferred listening level) and thenature of the loudspeaker/amplifier interfacevary so widely that it is not possible to lay downhard and fast rules about amplifiers and theloudspeakers they drive.

KEF loudspeakers are built to rigorous standardsof quality and consistency and the upper limits ofthe amplifier requirements shown are thosewhich the loudspeaker in question should handlewithout distress or damage when used undernormal domestic conditions.

If higher than specified amplifier powers areused, great care should be taken to avoidabnormal conditions such as switch-on surges or

gross distortion, either of the amplifier or theloudspeaker, resulting in power peaks greatly inexcess of the ratings specified. Care should betaken as the possibility still exists under certainconditions (such as excessive bass or trebleboost caused by tone and/or loudness controls,graphic equalisers, etc.) that the loudspeakerscan be overloaded and damaged. The lowerlimits of amplifier power are those necessary togive a reasonable sound pressure level underdomestic conditions.

Remember it is easier to damage theloudspeaker by using a small amplifier driven intodistortion by too much volume, possibly withbass and treble boost, than by using a largeramplifier which has power in reserve.

If in doubt, ask the advice of your retaileror consultant.

Amplifier Requirements and Power Handling

Models 201/2, 203/2, 205/2, 207/2 and 206/2ds

1716

HF Adjustment

The ‘HF Adjust’ A and B terminals control thehigh frequency output of the loudspeaker.This facility allows the user to adjust the‘brightness’ of the loudspeaker to suit listeningroom acoustics, partnering electronics andpersonal taste.

Four settings for tweeter output level arepossible +0.75, 0 (‘flat’), -0.75 and -1.5dB.For a‘brighter’ or ‘sharper’ sound select +0.75, toremove brightness select -0.75 or -1.5dB.The adjustment is made by screwing one,both or neither of the gold plated screw capsinto the HF Adjust ‘A’ and ‘B’ terminals,according to the table below. The default settingis 0 (‘flat’) - one screw cap in terminal ‘B’.

These adjustments as mentioned earlier areprovided not only for ‘room tuning’ butto allow a more sympathetic partnering tosome electronics.

Amplifiers that may have either a very forwardor bright presentation can be tamed or equallythose that have quite a warm presentation canbe given extra sparkle, it is your choice.

ModeHF

level (dB)Cap

A B

1.

2.

3.

4.

in +0.75

2.

1.

out

in

in 0.00

3. in out -0.75

4. out out -1.50

1234

Level (dB)

Frequency

2 kHz

+0.750.00

-0.751.50

The two centre channel loudspeakers,Models 202/2c and 204/2c, incorporate a twoposition ‘Free Space/Television’ Uni Balance thatadjusts the bass level depending on whether theloudspeaker is mounted freestanding or close toa TV or wall boundary. In the Model 202/2c the

‘television’ setting corrects the bass responsefor when the loudspeaker is placed on top of,or directly underneath, a TV. In the Model204/2c the ‘television’ setting corrects the bassresponse for when the loudspeaker is placed ona stand close to a wall.

HF Adjustment Models 202/2cand 204/2c

The two centre loudspeakers Models 202/2cand 204/2c incorporate a two position highfrequency level adjustment which allowscompensation for the sound attenuation when

the loudspeaker is positioned behind a typical acoustically transparent projection screen,see below. Select ‘Screen’ when the loudspeakeris positioned behind a screen.

Placement Adjustment Models 202/2c and 204/2c

NORMAL SCREEN

FREE SPACE TELEVISION

H.F.ADJUST

L.F.ADJUST

0

300 Hz

Level (dB)

Frequency

NORMALSCREEN


H.FADJUST

L.FADJUST

NORMALSCREEN


H.FADJUST

L.FADJUST 1

2

Mode

LFlevel (dB)

0.0

-3.0

300 Hz

Level (dB)

Frequency

1

2

Mode

LFlevel (dB)

0.0

-2.0

300 Hz

Level (dB)

Frequency150 Hz50 Hz

1

2

Mode

LFlevel (dB)

+0.750.00

NORMAL SCREEN


H.F.ADJUST

L.F.ADJUST

0.00+0.75

2 kHz

Level (dB)

Frequency20 kHz

NORMALSCREEN


H.FADJUST

L.FADJUST

SCREEN

TELEVISION

H.FADJUST

L.FADJUST

Mode

LFlevel (dB)

LF Adjustment

Tri-wiring/Tri-amping Terminals

The three sets of input terminals are linked by ahigh quality shorting cable. Removal of this cablewill allow the LF, MF and HF sections to beconnected separately, either by a parallelconnection from one amplifier (known as tri-wiring) or to separate power amplifiers

driven from the same pre-amplifier(tri-amping). Further adjustment of this cable will allow connection of just two (pairs of)adjacent terminals together for Bi-wiringand Bi-amping.

x4

Attaching Shorting Links

1918

x8

x4

Loudspeaker single wire connections

Loudspeaker bi-wire connections

Loudspeaker tri-wire connections

Single, Bi and Tri-wire Connections

2120

x4

x2

Centre loudspeaker single wire connections

Centre loudspeaker bi-wire connections

Centre loudspeaker tri-wire connections

x8

x4

Loudspeaker bi-amplification connections

Loudspeaker tri-amplification connections

Loudspeaker single amplification connections

2322

x4

x2

Centre loudspeaker single amplification connections

Centre loudspeaker bi-amplification connections

Centre loudspeaker tri-amplification connections

Poor quality cables can seriously compromisethe overall sound of your hi-fi system.KEF recommends that high quality loudspeakercable be used for connecting your ReferenceSeries loudspeakers. It is good practice to keepthe cables as short as possible.

The left and right channel loudspeaker cablesshould, wherever possible, be the same lengthotherwise there may be a perceptible change inoutput level between the loudspeakers.

Dedicated grille assemblies are factory fitted toeach loudspeaker. However, if you wish you mayremove the grille by gently pulling it forwardtoward you. The grille is held on via ‘pegs’ thatlocate into the front baffle grille-peg sockets(or magnets which hold the top Uni-Q driverarray grille). If required, the grilles may beremoved during use, but KEF recommendsreplacement following use.

KEF suggest removal of the grille for seriouslistening. For cleaning purposes, the grillesshould be removed from the cabinets andbrushed lightly with a soft brush. Alternatively,use a variable suction vacuum cleaner, with softbrush attachment.

Loudspeaker Cables

Grilles

Your KEF Reference Series loudspeakers areguaranteed against manufacturing defects in bothmaterials and workmanship. For further detailsof how this guarantee affects you, please readthe enclosed Warranty leaflet.

It should be noted, however, that failure ofthe loudspeaker due to abuse, improper orinappropriate use and/or operation or damagecaused by other faults in your system are NOTcovered within the terms of the guarantee.

Loudspeakers are inherently reliable and rarelygive trouble. It is important to remember thatfaults arising in any part of the reproducingsystem will be heard via the loudspeakersand therefore when faults occur, careful andanalytical diagnosis will be required to locate theactual source of trouble.

Loudspeakers cannot generate hiss or hum.Spurious noises of this type generallyoriginate in the electronic sections of theequipment or even in the programme sourceitself. Faults in a loudspeaker will be audibleon all programme sources. A fault which is evident only when playing CDs but not,for example, when using a radio tuner is unlikelyto originate with the loudspeakers.

Service problems should be discussed in the firstinstance with the dealer from whom theloudspeakers were originally purchased.Generally, warranty claims are best handledby your dealer. However, in case of difficulty,please contact:

Customer Services DepartmentKEF Audio (UK), Eccleston Road, Tovil,MAIDSTONE, Kent, ME15 6QP UK

Telephone No.: +44 (0)1622 672261Fax No.: +44 (0)1622 750653www.kef.com

Service Information

Warranty

2524

Specifications

Design : Bass reflex four-way floorstanding loudspeaker,

magnetically shielded.

Drive Unit Array : 2 x 250mm (10in.) LF

1 x 250mm (10in) LMF1 x 165mm (6.5in.) Uni-Q MF

including a 25mm (1in.) titanium HF

Frequency Response :(@ 15° horizontally off axis ± 3dB)

40Hz - 60kHz

Crossover Frequencies : 120Hz, 350Hz, 2.3kHz

Amplifier Requirements : 50 - 400W

Sensitivity : (2.83V / 1m)

91dB

Maximum Output : 117dB

Impedance : 8Ω (3.0Ω min )

Bass Extension : 26Hz (-6dB)

Weight : 66Kg (145lbs)

Dimensions (H x W x D) : 1226 x 400 x 685 mm

48.2 x 15.7 x 27 in.

Finishes :Piano Black

High Gloss CherryHigh Gloss American Walnut

Satin Sycamore

MODEL 207/2

Design : Bass reflex three-way floorstanding loudspeaker,



1 x 165mm (6.5in.) Uni-Q MF including a 25mm (1in.) titanium HF


45Hz - 60kHz

Crossover Frequencies : 400Hz, 2.3kHz



90dB


Impedance : 8Ω (3.2Ω min )


Weight : 33Kg (72.6lbs)


43.5 x 11.2 x 17 in.



Satin Sycamore

MODEL 205/2

Design : Bass reflex three-way floorstanding loudspeaker,


Drive Unit Array : 2 x 165mm (6.5in.) LF

1 x 165mm (6.5in.) Uni-Q MFincluding a 25mm (1in.) titanium HF

Frequency Response : (@ 15° horizontally off axis ± 3dB)

50Hz - 60kHz

Crossover Frequencies :

300Hz, 2.3kHz



89dB


Impedance : 8Ω (3.2Ω min)


Weight : 26.5Kg (58.3lbs)


40.2 x 9.8 x 15.9 in.



Satin Sycamore

MODEL 203/2

Design : Bass reflex three-way bookshelf loudspeaker,



1 x 165mm (6.5in.) Uni-Q MFincluding a 25mm (1in.) titanium HF


55Hz - 60kHz

Crossover Frequencies :

450Hz, 2.5kHz



86dB





Dimensions (H x W x D) : 417 x 248 x 405 mm16.4 x 9.8 x 15.9 in.



Satin Sycamore

MODEL 201/2

2726

Design : Closed box three-way dipole loudspeaker,



2 x 165mm (6.5in.) Uni-Q MFincluding 2 x 25mm (1in.) titanium HF


65Hz - 60kHz




88dB




Weight : 11.6kg (25.5lbs)




Satin Sycamore

MODEL 206/2ds

Design : Bass reflex three-way centre loudspeaker,





53Hz - 60kHz

Crossover frequencies : 400Hz, 2.3kHz



90dB



Bass Extension: 40Hz (-6dB)

Weight : 34.6Kg (76lbs)


7.9 x 43.4 x 16.7 in.



Satin Sycamore

MODEL 204/2c

Design : Bass reflex three-way centre loudspeaker,





65Hz - 60kHz




89dB








Satin Sycamore

MODEL 202/2c

29

KEF was founded in 1961 by an electricalengineer named Raymond Cooke in a NissenHut on the premises of a metalworkingoperation called Kent Engineering & Foundry(hence KEF), on the banks of the River Medway,near Maidstone in Kent.

From the beginning KEF was destined to becomea company with a flair for the unusual andcontroversial in terms of loudspeakerengineering, design, and use of materials.Within a year, KEF, under Cooke’s outstandingvision, was planning loudspeakers with bass unitsusing foil-stiffened, vacuum-formed, expandedpolystyrene diaphragms and a Melinex or Mylartweeter. This idea was manifested in the K1,an immediate success, followed by the bookshelfmodel, Celeste, a loudspeaker with an evenmore significant commercial success and onethat helped secure the early financial stability ofthe new company.

Re-establishing a previous relationship with theBBC in 1966, Cooke was interested in adoptinganother material, Neoprene (an artificial rubber)to help maintain sound quality in the mid-band byusing it as the surround to the loudspeaker

diaphragm, while using new materials for thediaphragm itself. Cooke was always looking fornew materials and settled on Bextrene as asolution, as its lightweight plastic sheet-likeproperties were flexible enough for shaping andthe material remained stable under varyingtemperature and moisture conditions and wassmooth and consistent over a wide bandwidth.As a result, in 1967, two new drive units, the 5in.B110 and 8in. B200 appeared which, with theircountless applications, found use in some 3million systems from KEF and many otherloudspeaker brands throughout the world.A new, smaller tweeter also arrived, the T27,which led to the most famous BBC/KEFcollaboration, the LS3/5A, of which some100,000 units were sold world-wide.

During the 1960’s KEF flourished.Loudspeakers such as the Concord,Concerto and Cresta and then, in 1969,the Chorale began to shape the company’sgrowing reputation as ‘The LoudspeakerEngineers’, a fact justly recognized in 1970 whenKEF received the first of two Queen’s Awardsfor Export Achievement.

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By 1973 the company was developing theconcept of computer assisted ‘Total System’design, at a time when the world’s very first 4-bitmicroprocessor was still in its infancy.KEF engineers, using a given set of parameters,could for the first time actually “see” what theresponse characteristics of a loudspeaker systemwould be. KEF was the first loudspeakercompany in the world to take the newtechnology seriously in order to achieve this.Now it was the use of computers and digitaltest methods which provided the KEF engineerswith the relevant crossover and drive unitdata at a glance, thus dramatically improvingtheir ability to produce loudspeakers ofoutstanding accuracy. Amongst other benefits,KEF loudspeakers could now be computermatched as an almost identical pair - to withinone-half of a dB.

1973 then saw the introduction of the first KEFReference Series Model, the 104 which sweptreviewers, distributors, retailers and customersoff their feet. The archetypal ‘domestic monitor’104 provided the standards of a broadcastmonitor loudspeaker in a domestic package,probably for the first time.

With the installation of a Hewlett Packardcomputer at the Maidstone Head Office in 1975,the Corelli, Calinda, and Cantata were alldesigned under the total system concept andwith them came a second Queen’s Award forExport in the same year.

1977 saw the most radical KEF design yet in theModel 105 which apart from setting newstandards for flat frequency response introduceda design by which the mid and treble were splitfrom the bass box and placed within a contouredmoulded enclosure above the bass enclosure.The added ability to angle the separate uniquehead unit provided the opportunity for the userto tailor the 105 to his or her own environment.The loudspeaker was of such general importanceand consumer interest that a leading quality UKNewspaper, The Daily Telegraph, featured theModel 105 on the front cover of its magazinesupplement. More Reference Models were tofollow. 1978 saw the launch of the 101 and103 and, in 1979 a further refined 105/2Model appeared.

Ten years of growth world-wide followed,peaking with a massive onslaught on the lucrativeand influential US market in 1985 with thesetting up of KEF Electronics of America, seen asthe appropriate recognition of this importantmarket-place.

1986 saw more activity amongst the now worldfamous KEF Reference Series; the 104/2, alwaysregarded as one of the world’s truly outstandingloudspeakers since its 1984 launch spawned the107, in reality an evolution of the 105/2 but withKEF’s coupled-cavity bass loading, a systemwhich positions the drivers internal to theenclosure, each separately loaded and firing intoa third common chamber which delivers verytight and accurate bass to the listening area via asubstantial front-mounted port. This combinesthe taut sonic character of a sealed box with thehigher sensitivity of a reflex design and succeedsin providing a huge boost to bass performance.Also came the 102 and the 103/3, both acceptedby recording and broadcast engineers asideal monitors. KEF’s reputation asloudspeaker engineers was set in stone.As well as the coupled-cavity bass loadingsystem, KEF Reference loudspeakers boastedsuch highly sophisticated features as a conjugateload network technique, which makes even acomplicated loudspeaker design simplicity itselffrom the amplifier’s perspective and a heavilydamped midrange module which preserves lowcoloration and fine stereo. A force cancellingrod, fitted between the vertically opposed bassunits was an added introduction, eliminating thepossibility for coloration caused by woofervibrations exciting the enclosure panels.

Amidst all this excitement, 1988 also brought inthe birth of the KEF Custom Installationloudspeakers, a move made in response to newworld market demands. The same exactingengineering standards were naturally applied tothe range and the CR200F and its sub-basspartner, the CR250SW set new standards fromin-wall/ceiling units.

Then, again in 1988, came Uni-Q. A designprocess, painstakingly evolved by KEF overseveral years, by which a single point source atlast became a reality. The HF units made use ofa rare-earth magnet material, Neodymium/Iron/Boron which was developed for the NASASpace Programme.10 times more powerful thana conventional loudspeaker magnet, this materialallowed KEF engineers to make a tweeter smallenough to fit within the bass unit coil former atthe precise acoustic centre of the cone.KEF’s Uni-Q technology delivered well-definedstereo imaging over a much wider listening areawithout the need for the time honoured sacred“hot-spot” in the listening room. The 105/3 wasa massive success, bringing together, not justUni-Q (now in its second generation form),but all of KEF’s magnificent technology -coupled-cavity bass loading, conjugate loadmatching, force cancelling rod, computermatched crossovers and drive units, even handpair-matched veneer finishes - in fact almosteverything by which KEF had made its name asthe world’s foremost loudspeaker company -in to one product. It was voted Best ImportedSpeaker by the Japanese Press in 1992.

‘Total System’ design testing equipment

The Model 105/3

The 1970’s The 1980’s

Uni-Q Technology

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KEF’s acclaimed Reference Series

Under new ownership in 1992 KEF Audio founditself equipped with new ideas, new personalitiesand new products. But the same philosophies ofsolid engineering and innovation to provide thefinest quality product available at its particularprice-point remained firmly at the bed-rock.

In 1994 and 1995 the company brought out theversatile and appealing Q Series, offering all thebenefits of a third generation Uni-Q driver butin a shielded format for AV use, together withthe multi-award winning Model 100 CentreLoudspeaker, the Model 90, the new Model200C and the Reference Series Models One,Two, Three and Four. KEF also introduced thenew entry level Home Theatre System for trueaudiophile home theatre sound at a price to fitmost pockets. At the end of 1994 the companyhad quietly launched three loudspeakers thatwere to become one of the most spectacularsuccess stories in recent KEF history.These were simply called Coda; affordableloudspeakers that took the world’s Press bystorm, the baby Coda 7 clinching the covetedUK Magazine What Hi-fi?’s “Best Buy”Loudspeaker of the of the Year Award for 1995.

KEF’s founding father, Raymond Cooke O.B.E.,sadly died during 1996, but with the knowledgethat all of his original and noble principlesremained intact, and would always do so.

Recognition that year for the Reference SeriesModel Four had reached a peak with world-wideacclaim. Reviews by internationally famed andrespected writers were quick to praise themerits of the company’s new flagship model withits fourth generation Uni-Q driver and to pointout the sheer engineering excellence of thecompany - an unswerving KEF attribute for over30 years. Comments such as “the best I’ve had inmy listening room.” from the US magazineStereophile and “KEF’s best yet” from UKmagazine Hi-fi News were just two of the manyplaudits showered on the Model Four.

The home theatre series boomed and thecompany introduced the Model 20B, a babybrother for the Model 30B active subwoofer.The Coda Series, particularly the Coda 7,continually outsold competing brandsthroughout the world. 1996 also saw the launchof the new Q Series and the new MonitorSeries, superbly crafted loudspeakers to meetthe challenges of the next century. Both rangesepitomise KEF’s total commitment toengineering qualities beyond all. As the 90’s drewto a close, KEF introduced the Reference SeriesModel 109 - The Maidstone. Over thirty fiveyears of technical excellence, innovation indesign and award winning engineeringcombined in one stunning loudspeaker.(Pictured Opposite).

The 1990’s

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The millennium ushered in a new era ofgroundbreaking audio innovation.

Among the most important was the launch of anew Reference Series - the forerunner of today’sdesign - in 2002. This redefined the benchmarkfor high-end loudspeakers by incorporatingsignature KEF technologies such as Uni-Q andthe ‘pod’ concept.

The decade had begun with the introduction of aproduct destined to become a design icon in itsown right: the KHT (KEF Home Theatre) 2005system. With satellite loudspeakers nicknamed‘KEF eggs’ because of their distinctiveelliptical shape, KHT2005 represented a realbreakthrough not only in terms of the buildquality and sonic performance that it offeredbut at a price that many found “very reasonableindeed”.

With the rising demand for home entertainmentsystems, the KHT series steadily grew toencompass both smaller and larger variants.The concept proved a worldwide success,with all models earning enthusiastic reviews anda plethora of awards, and the expanded rangeremains popular today.

Another patented KEF innovation of the 21stcentury was Acoustic Compliance Enhancement,or ACE. This technology was developed in theconstant quest to resolve a fundamental dilemmaof loudspeaker design: how to optimise thetrade-off between the large cabinet size requiredfor maximum bass extension and populardemand for smaller, less obtrusive loudspeakersin modern living rooms.

ACE largely succeeded in overcoming theseconflicting constraints by adding granules ofactivated carbon inside the driver enclosures.By a molecular process known as adsorption,the presence of the granules makes eachenclosure sound twice as big as it actually is.

Yet more KEF innovations soon followed.The KIT (KEF Instant Theatre) concept, forexample, proved an immediate hit - an integratedmultimedia home entertainment system forconsumers who want a complete, user-friendlypackage that offers quality sound without beingcomplicated to set up.

One of the most revolutionary aspects of thedesign is that it delivers the apparentlyimpossible: a three-dimensional surround soundimage from only two loudspeakers. This wasachieved by adding two flat panel drivers behindeach front loudspeaker driver to act as rearloudspeakers by radiating the sound behindthe listening area. This radical concept hassince been applied to other KEF homeentertainment products.

The launch of the new Q Series in 2005further strengthened KEF’s position as anacknowledged market leader in mid-pricedaudiophile quality loudspeakers. With its highperformance Uni-Q driver array, distinctivecurved cabinets and outstanding build quality andfinish, the new range was soon being referredto as “the baby Reference”.

Since then though, the Reference has evolvedfurther still. True to our vision and roots ashigh-end audio designers, KEF engineers havebeen concentrating on raising the bar in terms ofultimate sonic performance. And the result,it has to be said, is outstanding. When the latestKEF Reference technologies were showcased atthe prestigious High End 2006 audio show inMunich, prototypes for our new ‘Austin’(pictured opposite) concept loudspeakers werevoted by some the best sound of the show inindependent comparative tests.

Now as in ‘61, it’s all about greatness by design.

The 2000’s

GP Acoustics (UK) Ltd., Eccleston Road, Tovil, Maidstone, Kent, ME15 6QP U.K. Telephone: + 44 (0)1622 672261 Fax: + 44 (0)1622 750653

GP Acoustics (US), Inc., 10 Timber Lane, Marlboro, New Jersey 07746 U.S.A. Telephone: +(1) 732 683 2356 Fax: +(1) 732 683 2358

GP Acoustics GmbH, Heinrichstraße 51, D-44536 Lünen, Deutschland. Telephone: +49 (0) 231 9860-320. Fax: +49 (0) 231 9860-330

GP Acoustics (France) SAS, 39 Rue des Granges Galand - BP414, 37554 Saint Avertin CEDEX, France. Tel : +33(0)2 47 80 49 01 Fax : +33(0)2 47 27 89 64

www.kef.com

Documents

Important Safety Information - · PDF fileImportant Safety Information 1 General Care of Your System 1 Contents 3 Introduction 5 Overview of Common Features 6 ... Internally, however,