Knoll MR1250V User manual

Six stereo power
amplifiers with
individual volume
control electronics
Version 3.4
INSTALLATION
MANUAL
MR1250v
MR1250vf
2
CongratulationsandthankyouforchoosingtheKnöllMR1250vpower
amplifier.TheMR1250visdesignedtomeettheamplifierneedsof
custominstalledmulti-zonesystemswherehighqualitysoundisa
specificrequirement.
Key Features:
1.Individualmute,volume,bass,trebleandbalanceadjustment.
Eachofthesixstereochannelsfeatureadjustmentsforbass,trebleand
balance.Individualroomkeypadscontrolvolumeand mute.Any
keypadorRB8remotecanturnthesystemoff.
2.Costand size efficiency. The MR1250v consists of a total of 6
stereopoweramplifierswithindividualvolumecontrolelectronicsinone
3-1/2"highenclosure.Eachpoweramplifierchannelcandeliver50
wattsRMS.
3.Automaticprotectioncircuitry.EachMR1250vchannelis
individuallyandfullyprotectedagainstlowimpedance,overheating,
overloading,overvoltageandundervoltage.Theprotectioncircuitry
automaticallyrestorestheamplifierchannelassoonasitsparameter
returnstothesafeoperatingarea.
4.Externaltriggerout.An12VDCtriggeroutputisprovidedtoturn
othercomponentsonoroff.
5. Stackable17" chassis.The MR1250v can be stacked or placed in
a19"EIAequipmentrack(requiresRM1250kit).
6.LinkFeature.Certaininstallationsrequirethatsomeorallofthe
stereochannelsplaythesamesource.InsteadofYcords,"link"
cascadesanyorallofchannels2-6tochannel1(leftandright).
7.Datacascade.Forlargersystems,multipleMR1250v'scanoperate
intandemsoallMR1250v'sturnoffandontogetherandshareinfrared
signals.
8.Optionalfanversion. Forinstallationsthatrequirealotof"heavy"
usewerecommendtheMR1250vfwithaninternalfan.Somespeakers
thatclaimtobe4ohmswillcausetheMR1250vprotectionsystemto
activateaftermildusage.Afanwillhelptoavoidearlyprotection
systemdistortion.

Installation
InstallingtheMR1250vshouldberelativelyeasy.Withabitof
planning,theMR1250vwillgivetroublefreeserviceforyears.
1.Themostimportantconsiderationwheninstallingthe
MR1250viscooling.The MR1250v has alot ofpower packedinto
asmallchassissize.Wheninstallingitinanequipmentstack,itshould
bethetopcomponent.Itneedsatleast3"-5"ofspaceabovethe
amplifiertoallowforadequateconvectioncooling.
2.WheninstallingtheMR1250vinarackwesuggestaddinga
3-1/2"blankaboveandbelowtheMR1250v.InmultipleMR1250v
installations,planfora3-1/2"blank(double)betweeneach
MR1250vanda3-1/2"blankonthetopandbottom.Amplifiers
shouldalwaysbethetopcomponentsinaracksystem.
3.IfMR1250vchannelsfrequentlyshutdownduetooverheating,
installafandirectedupfromtheMR1250vbottomcenter.
4.NeveroperatetheMR1250vinitsside,asthecoolingpotential
drops significantly when operated on the side.
5.ConnecttheMR1250vinputstothesourcecomponentoutputs
with good quality, short as possible RCA jack cables. Connect
eachchannelindividually.Theinternallinkfeaturecanonlybeusedif
thesourcecomponent(s)are ratedfora 4k ohm load.
6.ConnecttheMR1250vspeakeroutputstospeakersusinggood
quality speaker wire. Minimum 16 gauge copper wire is
recommendedwith14 gauge minimum forruns over30' (10m).
Note:IdeallytheMR1250vlikes6-8ohmloads.Connectingto4
ohmloadswon'thurttheMR1250vbutthosechannelsconnectedto
4ohmloadsmayoccasionallyshutdownduetooverloading.
Never connect the MR1250v to 2 ohm loads.
7.Install one or twoVC201or one VC201e oroneVC201f keypad
intheroomswiththespeakers.ForroomswithtwoVC201's,
connectthetwokeypadstogetherusingarunofcat5wirewithRJ45
connectors.Seeguidenextpage.Connectalleightindividualwires.
Fromeachroommakeahome runofcat5wire fromoneVC201to
theMR1250v.Theinfraredsignaltravelsonthesamecat5wire.
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installationcontinued...
8.Makesurethespeakersineachroomareconnectedinphase.
9.WheninstallingVC201eorVC201fkeypadsyoumayneedto
connectupto4emitterstotheIREmitterportsontherearofthe
MR1250v.
10.WhenconnectingtwoormoreMR1250v'sinthesamehome,
connecttheampstogetherusingstereo3.5mmplugs(allthreewiresare
used)tothedataplugontherearoftheMR1250v.TheMR1250v's
sharepoweronandoffdataaswellasinfraredsignals.
11.ConnecttheACpowerintoanoutletthatcansupplyatleastsix
amps(700watts)dedicatedtoeachMR1250v.
MR1250v 12 Channel Power Amplifier
Inputs: 12 gold RCA jacks
Inputimpedance: 24 k ohms
Outputs: Gold 5 way Binding posts
Output power: 50 watts RMS per channel (8 ohms)
Peak output power: 100 watts RMS per channel (8 ohms)
Idealimpedance: 6-8ohms
Freq. response: 10 Hz - 40 kHz +/- 1 dB (1w)
S/N ratio: over 105 dB A weighted 50 watts
THDdistortion: <0.1% 20 Hz to 20 kHz
IMD distortion <0.01% 60 Hz 7 kHz 4:1 (SMPTE)
Triggercontrol: 12VDCoutputon3.5mminputjack.
Power: 750 watts 117 VAC
Dimensions: 17" x 3.5" x 10.5"
Weight: 21 lbs (9.6 kg)
Caution:Neverlistentosoundthatisdistorted.Ifdistortedsoundis
heard,turnthevolumedownimmediatelyorspeakerand/oramplifier
damagecouldoccurthatisnotcoveredbythewarranty.Ifthis
problempersists,contactyourdealer.
UserAdjustmentsandService:Therearenoadjustmentsinthe
MR1250v.Yourinstallermaymakecertainbass,trebleandbalance
adjustmentsontheMR1250vrearpanel.
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InCanada:
11791 Machrina Way #120
Richmond, B.C. V7A 4V3
KnöllSystems
tel [phone]
fax [phone]
CCOPYRIGHT 1998-2003, Knöll Systems, All Rights Reserved
InAmerica:
145 Tyee Drive, #1206
Point Roberts, WA 98281
Limited Warranty
Knöll Systems warrants its electronic products sold in Canada and the USA by
authorized Knöll dealers to be free from defects in materials and workmanship.
This warranty extends for three full years from the date of purchase by the
consumer. Any products returned freight prepaid to Knöll Systems and found to
be defective by Knöll Systems within the warranty period will be repaired or
replaced at Knöll Systems option, at no charge. Knöll Systems will not be
responsible for the actual cost of installation or removal of the product, nor for
any consequential or incidental damages. Some states do not allow the exclusion
or limitation of incidental or consequential damages, so the above limitation or
exclusion may not apply to you. This warranty gives you specific legal rights.
You may have additional rights which vary from state to state. Knöll products
sold outside of Canada and the USA may be covered by warranties provided by
an authorized Knöll distributor. Please contact the distributor in the country that
the Knöll product was purchased.
Printed in Canada
Keypads and Remote Control
RB8 Eight button remote control. For use with VC201f keypad to
control functions ofMR1250v. Power,mute, volumeup and
volume down functions enabled. Inputs 1 thru 4 disabled.
VC201 Basic paddle style keypad to control: room power on, room
poweroff, all poweroff, volume up,volumedown, muteand
unmute. Includes green led status indicator and six green led
volumelevelindicators.Availableinwhite,ivory(bone)and
almond colors.
VC201eSame as VC201withinternal pass throughinfraredreceiver.
Allows use of component (DVD, CD, tuner satellite dish, etc.)
remote controls to adjust (component only) settings.
Available in white, ivory (bone) and almond colors.
VC201f Sameas VC201 withinternalinfrared receiver capable of
controlling MR1250vand passthrough. Designedforuse with
RB8 remote control. Remote control can do even more
MR1250v functions than keypad.
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Caution:TheMR1250vcontainsnouserserviceableparts,sodo
notattempttoopenorrepairtheMR1250v.Referservicingtoa
qualifiedtechnicianonlyorcontactthefactoryforinformation.
Troubleshooting
IfaproblemisencounteredwiththeMR1250v,themostexpedient
procedureistolocatetheproblemandifpossiblerepairitbefore
requestingservice.Besuretocarefullycheckothersystem
componentssuchascontrollers,CDplayers,volumecontrols,wiring,
speakers,etc.thatmaybeatfault.
Problem Action
Powerindicatordoes 1.CheckthattheMR1250vispluggedin.
notlight-nosound 2.TesttheACoutletwithalamp..
3.CheckthattheMR1250vpowerbuttonis
on (in).
Soundcutsout 1. Verify speaker impedance is 4-16 ohms.
Changingspeakersmayberequired.
2.CheckiftheMR1250vfeelshot.Ifit's
hot,increasecooling-seeInstallation.
Sound is distorted 1. Turn the volume down
2. Check speakers for damage.
3. Check inputs for proper levels.
Sourceoutputlevelsmayneedadjustment.
4.Speakersmayhavelessthan4ohmrating
MR1250vdoesnot 1.PressanyVC201keypad"down"button
turnoff all the down untilthebottomVC201led
blinksthreetimes.TheMR1250vshould
powerdown and the MR1250vled turns
red(idle).BeforeturningtheMR1250v
powerswitchtooff (out)wealways
suggesttheMR1250vbeidling.
Speaker pops when 1. Speaker may need resistor placed across
amp turned on or off terminal. Suggest 2k0 1/4 w resistor.
Discharges speaker internal capacitor.

MR1250v Rear Panel
12Vtrigger out
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5
1
234
5
1
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5
1
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1
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AC120V
8 amps
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L
R
3L+
Inputs Outputs
3L- 4L- 4L+
3R+ 3R- 4R- 4R+
12
L
R
1L+
TrebleBassBalance
Inputs Outputs
1L- 2L- 2L+
1R+ 1R- 2R- 2R+
56
L
R
5L+
Inputs Outputs
5L- 6L- 6L+
5R+ 5R- 6R- 6R+
Link-Out
Link-Out
Link-Out
Link-Out
Link-Out
Link (out position)
cascadeschannel1
to channels 2-6
Note 1: Ideal speakerimpedanceis 6-8
ohms. When using 4 ohm speakers,
MR1250vfwithfanmaybeneededto
obtainfull powerwithout distortion
caused by protection system.
brown
white/brown
orange
white/blue
blue
white/orange
green
white/green
RJ45 plug wiring guide
Room 1 TrebleBass Balance
Room 6
TrebleBass Balance
Room 5
TrebleBass Balance
Room 4
TrebleBassBalance
Room 3
Treble BassBalance
Room 2 Room 1 To Keypads
Room 2 Room 3 Room 4 Room 5 Room 6
Data
IREmitters
1 2 3 4
Room power on and
volume up button
Mute button (volume
level led blinks)
Room power on, volume
down and all room power off
button (hold down button for
three led blinks)
System status led and
infrared signal confirming
led (VC201e and Vc201f only)
VC201 Keypad functions
Volume level
indicator for
this room only
Infrared signal
receiver
(VC201e/fonly)
Note 2: With channels 2 to 6
linked to channel 1 the input
impedance is 4000 ohms.
Note 3: Keypad wire code:
brown c1 (led control)
white/brown c0 (led control)
orange infrared signal (hot)
white/blue downsignal(normally5VDC)
blue up signal (normally 5VDC)
white/orange ground
green c2 (led control)
white.green c3 (led control)