Krell Industries Preamplifier KRC 2 Quick start guide

A. INTRODUCTION
Thankyou for your purchase of the KRELLKRC-2.
remote control preamplifier. TheKRC-2combinesthe
latest eV.olutionsin preamL~lifiertechnologywitha radical
approaclato remotecontrol circuitry. The-KRC-2is part
oI" a newgener.ation, of KRELLproducts whereconve-
nienceis unitedwitla exceptionalsonicquality.
Toobtain the best performance.fromyour KRC-2,carefu.1
attention sh.ouldbepaid to its placement,installation anti
operation. Athor~oughunderstandingof these detail.s will
helpinsure satistactory operationandlonglife for the
KRC-2and related system components.
This Owner’sReferenceis divided into several sections,
eac.h designedto perfor_,m a different function. Asyou
read through the Owners Referenceyou will beco.me
bet.ter acquaintedwiththe features andfunctionsthat
makethe KRC-2a superb value, AQuestion and Answer
section is included wtiere answersto commonquestions
are provided. Shouldyouhave any questions or sugges-
tioffs pleasefeel free to contactyourauthorizeddeareror
the KRELLstaff for assistance.
In the unlikely event that your.KRC-2.shouldrequire
service, youwill bepleas6_dto ~lgaowtlaat it is backedbya
compretiensiveCustomerbatistaction policy and one of
the mostadvancedservice facilities in the industry. For
detailed informationon the termsand conditions of ser-
vice, please consult yourwarrantyregistration card, your
authorized KRELLDealer or Distributor.
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B. TABLE OF CONTENTS
4
5
6
8
10
11
14
15
UNPACKING AND ASSEMBLY
BASIC INSTALLATIONAND OPERATION
INPUT AND OUTPUT CONNECTIONS
BASIC PREAMPLIFIER OPERATION
REMOTE CONTROL
QUESTIONS AND ANSWERS
SPECIFICATIONS
WARRANTYAND SERVICE INFORMATION
3

C. UNPACKING AND ASSEMBLY
1. Openthe boxand removethe top layer of foam. The
KRC-2and following items will nowbe visible:
KRC-2remote control
Warrantycard
ACpower cord
Owner’s Reference
NOTE:If any of these items are not included please
contact yourauthorized dealer immediatelyf6r assis-
tance.
3. Removethe plastic bag fromthe preamplifier and
remotecontrol.
NOTE:Saveall packingm.ate.rials. If you.mustship your
KRC-2in the future, repacl~the unit withtlae remote
control in its original packagingto preventtransit dam-
age.
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D. BASIC INSTALLATION AND
OPERATION
1. Placethe unit on a firm level surface free fromexces-
sive dirt or moisture..TheKRC-2is not particularly hum
sensitive, therefore other componentscan be placedon or
around the KRC-2.
2. If youare using the separate. KPEph.onostage withthe
KRC-2,the following connections apply:
NOTE:If you are not using the KPEproceedto step 3.
a. Unplugthe KRC-2from the wall ACreceptacle.
b. Locate the 9 pin DCpowerconnector labeled KPE
POWER.
c. Connectthe KPEwith the DCpowercable supplie.d
with the phonostage, to the KPEPOWERinput on the
KRC-2.
d. Plugthe KRC-2into the wall AC.receptac.le..The Pilot
LEDon the KPEshould illuminate along with the
KRC-2.Theinput select will default to the mutepo.sition.
Shouldthe KPEpilot LEDnot illuminate, unplugthe
KRC-2fromthe wall ACreceptacle and checkaI1 qf your
connections. Shouldyouhave difficulty poweringtlae
KR.C-2and the KPEtogether please contact Krell for
assistance.
3. If you. are not usingthe .KPE,plugthe ACcordinto the
receptacle on the backof the umt. Plugthe remainingend
into the .wall ACreceptacle.Thepilot LEDwill illumi-
nate, and the KRC-2will default to the Muteposition.
NOTE:While the KRC-2has superb regulation and does
not require a dedicatedACcircuit, westrongly advise
against any. connectionsthroughextensioncords or mul-
tiple ACadaptors. Highquality 15 ampline conditioners
or groundedACstrips are acceptable.
NOTE:The KRC-2provides two special remote connec-
tors on the.backpane]. Theseare providedfor future room
remoteand remoteslave formats. Please consult the
KRELLstaff for assistance on these developments.

E. INPUT AND OUTPUT
CONNECTIONS
CAUTION:Whenmaking connections to this component
or any other, makesure tlie poweramplifier is OFF.
CAUTION:Makesure all cable terminations are of the
highest quality, free fromfrayed ends, shorts or cold
solder joints.
1. Connectt.he left and right outputs of your source com-
ponents t.o the inputs on the KRC-2.The KRC-2is
equipped with 4 single-ended inputs., 2 balanced capable
inputs, a single endedtape input and tape output.
The single-ended and balanced inputs are labeled S-1
througti S-4, B-1a.nd B-2 respectively, to allow
customization in the set-up otyour system. There is. no
difference betweenthe four single-ended inputs, or ~e-
tween the two balanced inputs.
2. Connectthe output of the KRC-2to the input of your
power amplifier. The KRC-2has both Balanced outputs
via standard XLRtype connectors and single-ended
outputs via standard-RCAtype connectors.
Thepin assignment for the XLRconnectors is:
pin _1-=shield (ground)
p!n 2 = non-inverting input (hot)
pin 3 - inverting input
NOTE:The RCAcenter conductor for each channel is
wired in para!lel with pin 2, the non-inverted output.
Onlyone of these outputs should be connected to a single
stereo amplifier.
NOTE:Whenconnecting inputs or outputs to the KRC,
rememberthe balanced connections will have 6dBof
gain .m.ore than the single-ended connections. Whenlevel
matchingis critical in yourinstall, keepthis specification
in mind.
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REAR PANEL DESCRIPTION
INPUTS
Four single-ended inputs via standard RCAconnectors
S1
$2
$3
$4
Twobalanced inputs via standard XLRconnectors
B1
B2
TAPE
Tapeinput via standard RCAconnectors
TAPE OUTPUT
Record via RCAconnectors
MAIN OUTPUTS
Single-ended RCAoutput connectors
Balanced XLRoutput connectors
XLRinput and output pin configuration
p!n 1 Ground(shield)
p!n 2 0 degrees(non-inverting)
pin 3 180~egrees (inverting)
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F. BASIC PREAMPLIFIER
OPERATION
TheKRC-2has the flexibility of a remotecontrolled
devicebut doesnot require special attention in orderto .
performsimple functions. Tile KRC-2will function much
fike other K/ell preamplifiers.Theunit can be operated
fromthe front panelcontrols or via the remotecontrol.
All functionsavailable onthe front panel can also be
accomplishedfrom the KRC-2remotecontrol. This gives
you.the ability to sit in yourfavorite listening position
andcontrol aI1 preamphfierfunctions.
Noteson the VolumeControl:
Thelevel control on the KRC-2is quite uniquein that.the
output level is indicated by illuminated LEDsaroundthe
ou~tsideof the level control, not bythe physicalpo.sition
ot the level co.ntr.ol. Whenyou~changelevel withthe
remotecontrol, the position ot the level control knob-
does not change. Whenyou increase the volumemanu-
ally or by remotecontrol, indicator LEDswill illuminate
clockwise. Whenyoudecrease the volume,indicator
LEDsilluminate counter clockwise. Whenthe level is
fully off, noindicatorLEDswill bei!lu .m.inated.Thisis
becauselevel is electrically regulatedwithout the use of
a potentiometer.
Thelevel indicator display for the KRC-2can be
switched betweena bar graph modeand a single LED.
.mode.In the bar graphmodeall LEDsare illuminated to
the point wherelevel is. set. In the single LEDmodeonly
one-LEDis illuminated at the level setting. Tochange
frombar graph modeto ~single LEDmode,pressanil
hold the MUTEbutton tor .approximately 3-seconds..
Level will nowbe indicated with a single LED.Holdthe
MUTEbutton in again for 3 secondsto changethe dis-
play back to the bar graph.mode.Thedisplay can only be
changedvia the front panel. "-
t~OTE:Whenchangingthe volume,display, do not select
e muteposition beforetrying to changethe display.
Wh.enyouare chang.ing the volumedisplay and holding
in the mutebutton, the muteLEDwill not illuminate.
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Basic Operation:
1. Press the Mutebutton briefly on the KRC-2.
2. Turnthe volumecontrol fully counterclockwiseto the
Off position, no LED’silluminated.
3. Turnthe poweramplifier On.
4. Choosea listening sourceand.select that input by
pushing the correspondinginput button on the KRC-2.
5. Start playof the source.
turn6. Slowly _ the volumecontrol clockwise until you
reach a comtortablelistening level.
7. Whenchangingsources, return to the Mu.teposition
andor lowerthe volume.Thisinsures that tlae next
sourceyouplay will not be potentially damagingto your
systemwitti a highoutputtransient.
8. Enjoy
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FRONT PANEL DESCRIPTION
INPUT SELECTION
S1 selects S 1 input
$2 selects $2 input
$3 selects $3 input
B1 selects B1 input
B2 selects B2input
FUNCTIONS
TAPE selects Tapei~nputandallows
monitoringot Tapereturn.
PHASE Inverts absolutepolarity of the main
output
LEDilluminates whenphase is
reversed 180 degrees when
GAIN
MUTE
BALANCE<
BALANCE >
VOLUME
Low6 dB High 12 dB
LEDilluminates in high position
Nosignal output whenLEDis On
Left channelattenuation in 1 dB
increments and OFF
Rightchannelattenuation in l dB
increments and OFF
Customelectronic volumecontrol
(Seenotes in section F)
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G. REMOTE CONTROL
1. Whena function button on the remotecontrol is
~ssed, the blue pilot LEDwill flash on the KRC-2.
en the buttonis releasedthe flashing stops.
2. Thefunctions of the remotecontrol are described
below:
UParrow
DOWNarrow volumehigher volume lower
S1 selects S 1 input
$2 selects $2 input
$3 selects $3 input
$4 selects $4 input
B1 selects B1 input
B2 selects B2input
TAPE selects Tapeinput and allows tape
monitoring
PHASE 0 or 180degrees
LEDilluminates whenthe phase is
reversed 180degrees
GAIN Low6 dB High 12 dB
LEDilluminates in high position
MUTE
BALANCE <
BALANCE >
Nosignal output with LEDon
Left channelattenuation in 1 dB
increments and OFF
Right channelattenuation in 1 dB
increments and OFF
BATTERYINSTALLATION
NOTE:Batteries should be replaced whenthe KRC-2
functions fromthe remotecontrol are not readily
accessible.
1. Removethe four hex head screws from the bottom
12ortionof the remotecontrol’s front plate.
2. llemovethe backplate to exposethe battery storage
compartment.
3. Insert batteries (Refer. to the polarity drawingwhile
insertingthe batteries)
4. Replacethe backplate and insert the four hexhead
screws.
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H. OUESTIONS AND ANSWERS
.Q. WhenI turn up the volumeon the KRC-2a loud hum
is present fromttie loudspeakers.Whatcouldit be?
A. Humcan be causedby_several different disturbances.
Checkto makesure all of the cables in andout of the
KRC-2are sound and makingproper contact. Makesure
there are~no powersupplies orhuminducing components
on top ot or directly belowthe KRC-2.
Youalso could be experiencinga groundloop in the
system. Agroundloop can be ca.used whe.nseveral.
componentswith diffdrent groundpotentials are in the
system.Groundloops can often be easily correcte.d.
Consult your dealer or KRELLfor system grounding
considerations.
Q. Canthe KRC-2be used to control morethan one
system?
A. Yes, the KRC-2has both single end.ed and bala.nced
outputs that can be usedsimultaneouslyto control two
seperate systems.
Q. WhenI select the B 1 input on the KRC-2one channel
seemsto haveless gain than the other. Is something
wrongwith the preamp?
A. Morethan likely there is not a problemwith the
KRC-2.Thebalancedinput or output internal cable
terminationscould be incorrect. Switchthe suspect cable
to the other channelandvice versa to determinewhether
a cableis defective. If the problemswitchesto the other
channel,it is a defective cable. If the problemdoesnot
moveto the other channel and remainsthe sameafter
cables havebeenswitched, checkthe wiring at the input
of the KI~.C,2withthe sameprocess.If it is not cableor
sourcerelated call yourdealer or KRELL.
Checkto makesure there are no LED’silluminated in the
Balancecontrol sectionof the front panel. If there are,
correct the balanceby pushingthe balancecontol
switchesuntil no LEDson the balancecontrol section are
illuminated.
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Q. Whydo I have. to turn upthe volumeso high to get
musicat a normallistening level?
A. If your systemdoes not seem.to have enoughgain
overall, youare probab~lynot utilizing the balancedinput
or output capabihties ot the KRC-2.For every balanced
termination on the KRC-2yo.u increase the gain by 6dB.
If youstill haveto increasetlae gaintoo far, makesure
the KRC-2is in the HIGHgain position.
~. I camehomeone eveningand the pilot LEDin the
RC-2wasnot illuminated. Whatstiould I do?
A. Unplugthe KRC-2from the wall ACreceptacle and
checkthe. fusein the rear panel.If there is a 15reakin toe
wireinside the fuse, replaceit. If there is nobreakin the
fuse, donot try turningonthe preamplifi.eror replacing
.the fuse. Call yourdealer or KRELL.If tlae newfuse lets
thee unit turn onwhenyouplugit in, then fails shortly
atterward, call KRELLIndustries. If the fuse solves the
problem,carry onlistening as usual.
Q. WhenI push the function buttons on the KRC-2re-
motecontrol the preampdoes not respond. Whatshould I
do?
A. Checkor changethe batteries in the remotecontrol.
Theremotecontrol will not operate the preamplifier in
other roomsnot in the remotecontrol’s trajectory..Make.
sure youhavea direct path fromthe remotecontrol to the
preampfront.
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I. SPECIFICATIONS
GAIN
6dB orl 2dB
SIGNAL-TO-NOISE
< ,95 dBunweighted
THD
1K < 0.02%
20K < 0.02%
INPUT IMPEDANCE
47,000 ohms(47K)
OUTPUT IMPEDANCE
10 ohms
OUTPUT VOLTAGE
16 volts R.M.S.
DIMENSIONS
19.0" WIDE
14.5" DEEP
2.75" HIGHwith feet
WEIGHT
Unit only 20 pound_s
packed 26 pounds
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J. WARRANTYAND SERVICE
INFORMATION
Thereare no user-serviceable parts inside the KRC-2.The
KRC-2has a limitecl warrantyof fiv.e years parts and
labor. Returnfreight is includedin tlae warranty.The
warranty,per!od, beginson~thedate of purchaseandis
activated witla tlae return ot the enclosedWarra.ntyCard
anda copyof the Sales receipt. Pleasereturn tlae war-
ranty cardimmediatelyafter successful installation and
operation are completed.
Thewarrantyfor Krell products is valid ~ in t.he coun-
t~ry to whichtheywereoriginally shippeda.ndat tlae
ta.ctory. If youthinkthere are pr.oblemsw.itla yourunit,
pleasecontactyourdealer, distrit)utor or tlae tactory
~mmediately.
~heoperatingvoltageof this unit is determ,inedb.ythe
acto_ryandc.a.n only be changedbyan autlagrized
KREELdistrit~utor or the KR-ELLfactory. Anyunautlao-
[~zedvolta.ge cooversio~nwill voidthe warranty.Should
e operating voltage ot your KRC-2require changing,
contact KRELLIndustries.
Plea~s.edonot return, anyunit to KRELLfor repair with-
out first calling to cliscuss the problemandto obtaina
ReturnAuthorizationnumber.-Freightto the factory or
distributor is yourresponsibili.ty. Returnfreight to you
will be paid bythe factory or distributor. Anyunautho-
r.ized disassembly,.updatesor modificationsperformedto
the unit will voidthewarranty.
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1 KRELL INDUSTRIES
I45 Connair Road
Orange, Ct USA
06477-3650