KJB DNG-2300 User manual

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DNG-2300
Digitalwhitenoisegenerator
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UserManual
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2
Introduction
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Itiswell‐knownthatsoundpermeatesthroughwalls,doors,water,windowsandother
constructionsaswellasthroughvoids,cavitiesandventilationshafts.Thispropertyofmaterials
makesitpossibletointerceptconversationsconductedwithinpremiseswiththehelpofhighly
sensitivecontactmicrophones(electronicstethoscopes),windowlasersystemsorconventional
microphoneswithoutenteringthetargetarea.
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Wallcontactmicrophonescanpickupvibrationsfromtheplumbing,structures,walls,windows,
doors,floors,ceilingsandmore.Thelisteningdevicemaybeinanadjacentroom,orevenseveral
floorsorroomsawayattachedtoawall,pipeorotherfixture.Cavitiessuchasairducts,ventilation
shaftsorothervoidscanbeusedforinterceptingsoundfromanadjacentpremiseswithahelpof
conventionalmicrophones.Windowlasersystemsareableto"read"conversationsfromthe
premisesbysendingvisible,orinvisible,infraredbeamstotheglassandextractingthesound
vibrationsfromthereflectedrays.
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TheDNG‐2300generator,togetherwithitstransducersandspeakers,counteractsalltheabove
mentionedmethodsoflisteningbycreatingpowerful,non‐filterableinterferenceonthestructure
ofabuildingandwithinitsvoids.
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TheTD2300transducersareperfectlysuitedfortheDNG‐2300.Theyhaveanattractivedesign,
combineahighpoweroutputwithcompactnessandfitequallywellonwindows,wallsandother
structures.TheincludedmountingsetmakesitpossibletoinstalltheTD2300transduceronany
surface.Thetransducerpassesmostofthegeneratednoiseintothedesiredconstructioninthe
formofvibration,whilealsoproducinglessaudibleinterference.Thefrequencycharacteristics
optimallycorrespondtothespectrumofhuman'sspeech.
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Whiletransducersinjecttheirgeneratednoiseintosurfacesandstructures,stoppingthe
distributionofsoundthroughthem,theroleofaspeakeristofillvoids,cavitiesandventilation
shaftswithaudiointerferencetopreventleakageofsoundthroughtheair.TheSP2300isthe
recommendedspeakerfortheDNG‐2300.
Features
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Createspowerfulprotectionagainsttheleakageofalltypesofvibro‐acousticsbyinjectingnon‐
filterablenoiseintosurroundingstructuresandcavities
Suppresseswallcontactmicrophones,windowlasersystemsandwiredmicrophonesinside
walls,voidsandventilationshafts(airducts)
Isakeypartoftheprotectionsystemwhichalsoincludeswire‐connectedtransducersand
speakers
Generateswhitenoise–theoutputinterferenceisevenlydistributedthroughthespectrumofa
human'svoice
Has3independentoutputchannels:2xTRANSDUCERSand1xSPEAKERS
All3channelshaveindividualleveladjustment
EachTRANSDUCERSchannelcanfeedupto12transducersmountedonsolidstructures
(concrete/cement/bricks)andupto24transducersonlightstructures(glass,pipes,drywall,

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wood)
TheSPEAKERSchannelcanfeedupto12speakers
TheMUTEcontrolinputallowstheusertoturnoffthespeakerstemporarily
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Specification
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Powersource110‐220V,50‐60Hz
Dimensions6x17,5x25,4
Weight2.2kg
Outputchannels2xTRANSDUCERS
1xSPEAKERS
Peakoutputvoltage12V
TRANSDUCERSoutput 
Max.outputpower 2x10W
Frequencyresponse180‐5600Hz
Minimalimpedanceofload3Ohm
Max.quantityoftransducersperchannel24(lightstructures)
12(solidstructures)
SPEAKERSoutput 
Max.outputpower 1x8W
Frequencyresponse180‐7000Hz
Minimalimpedanceofload8Ohm
Max.quantityofspeakers12
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Suppliedset
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TheDNG‐2300isakeypartoftheprotectionsystemconsistingofanoisegenerator,transducers
andspeakers.Whilethegeneratorcreatesthenoise,thewire‐connectedtransducersand
speakerspassitontotheconstructionsandcavities.Sincethequantityofthetransducersand
speakersmayvary,dependingonthedimensionsoftheroom,possiblevectorsofattackandtype
oftheconstruction(windows,waterpipes,cavities,etc.),itispossibletoorderthestandardset,
whichincludesonlythegenerator,andadditionallyorderanyquantityofthetransducersand
speakers.AnotheroptionistopurchasetheDNG‐KIT1setwhichincludesthequantityof
transducersandspeakerssuitableformostcommoncases(smallormedium‐sizedroomwith1
window).
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*Transducersandspeakerstobeorderedseparately
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Standard*DNG‐KIT1
NoisegeneratorDNG230011
ACpowercord11
TransducerTD23004Ohm 12
SpeakerSP2300 2
Carrycase1

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Controls
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Frontpanel
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Figure1
1. Powerswitch
2. Levelindicator‐Channel1(TRANSDUCERS1)
3. Levelindicator‐Channel2(TRANSDUCERS2)
4. Levelindicator‐Channel3(SPEAKERS)
5. Level1adjustment‐Channel1(TRANSDUCERS1)
6. Level2adjustment‐Channel2(TRANSDUCERS2)
7. MutestateofChannel3(SPEAKERS)
8. Level3adjustment‐Channel3(SPEAKERS)
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Rearpanel
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Figure2
1. TRANSDUCERSoutputterminals–Channels1and2
2. MutingforChannel3(SPEAKERS):contactsopen–channelon,contactsclosed–channeloff
3. SPEAKERSoutputterminals–Channel3
4. ACpowerinput
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5
Installation
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Thecompleteprotectionsystemconsistsofthegeneratorandanumberoftransducersand
speakersuniformlyinstalledinaroomonthestructuresandwithintheaircavities.While
transducersinjectthegeneratednoiseintosurfacesandstructures,stoppingthedistributionof
soundthroughthem,theroleofthespeakersistofillvoids,cavitiesandventilationshaftswith
audiointerferencetopreventleakageofsoundthroughtheair.
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Carefullystudythepremisesforanypotentialpointsofacousticleakage.Notethemostsensitive
pointsfortheplacingofthetransducersandspeakers.Payattentiontothefollowingdetails:
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Structureoftheboundarywalls,ceilingandfloorandtheiraccessibilityfromoutside
Acousticisolationoftheentrancedoor
Windowsandtheirorientation
Presenceofpipes(theheatingsystem,watersupply,fireextinguishingsystem)
Presenceofvoidsconnectedwiththeadjacentrooms
Ventilationshaftsgoingoutofthepremises
Presenceofanyotheracousticleakagechannels
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Quantityandarrangementoftransducers
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Thereare2availableversionsoftheTD2300transducers.Thehigh‐power,4OhmTD2300,is
especiallygoodforsolidsurfacessuchasconcrete,cementorbrickceilingsandfloors,althoughitis
universalandcanbemountedonlightersurfaces.
Theeasy‐to‐wire16OhmTD2300suitslightsurfacessuchaswindowglass,wood,drywall,plaster
andpipes.
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Toestimatethequantityoftransducersusethefollowingsuggestions:
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OnwallstheTD2300transducersshouldbeinstalledevery2‐3meters,centeredbetween
floorsandceiling.Ifitisnecessarytopositionthetransducersclosertothefloororceiling
becauseofinteriordesigndemands,selectalesserdistancebetweenthetransducers.
Onfloorsandceilings–shouldbeinstalledevery6squaremeters
Onwindows–oneachwindowpane
Doors–One,placedadjacenttothecenterhingeonthedoorframe
Waterpipes–oneachpipegoinginandoutofthepremises
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Wiringandconnectionoftransducers
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Whenthequantityoftransducersisestimatedandtheyaregroupedbythesurfacetype,itis
possibletoselectthewiringvariant.Dependingonthenumberoftransducersneeded,choosea
wiringdiagramfromthebelowpictureforeachchannelofthenoisegenerator.
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TD23004Ohmtransducers
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Toprovideanequaloutputpower,andtofollowthedemandsofoutputimpedance,theTD2300

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4Ohmtransducersareunitedasacombinationofserialcircuits(chains)connectedinparallel.
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Theoutputpowerisdividedbetweenthetransducersandisinquadraticdependenceontheir
quantityinaserialchain.Thepercentage%showstherelativepowerproducedbyatransducer,
comparingtothe"basic"variantwith2seriallyconnected4Ohmtransducers.
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Quantityof
transducersina
serialchain
Relativepowerproducedby
4Ohmtransducer
Typeofsurface
2100%Solid
344%Solid
425%Solid/Light
516%Light
611%Light
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Thepercentagereflectstherelativepower,whiletherealoutputwilldependonthegenerator's
volumecontrol(LEVEL).Thetransducerswithahigherrelativepowercanbeinstalledonanytypeof
surface,includingthelightconstructionifthecorrespondingoutputissettoalowerlevel.
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Itisrecommendedtopassmorepowertothetransducersmountedontosolidsurfacessuchas
concrete/cement/brickwall,ceilingandfloor.Inthiscasethequantityofseriallyconnected
transducersineachchainshouldnotexceed3‐4pcsfor4Ohmversion.
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Lightsurfacessuchaswindowglass,wood,drywall,plasterandpipesusuallydemandlesspower
andallowfortheconnectionofmoretransducersinaseries(upto6).

    
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 
  
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Thetransducersmarkedas100%,44%and25%canbemountedonsolidsurfaces.Thetransducers
markedas11%,16%and25%‐onthelightsurfaces.
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TD230016Ohmtransducers
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QuantityofRelativepowerproducedby Typeofsurface

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transducersina
serialchain
16Ohmtransducer
1100%Solid
225%Solid/Light
311%Light
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  
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AssignmentofTRANSDUCERSoutputs
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TheDNG‐2300hastwoTRANSDUCERSoutputs,eachcapableoffeedingupto12‐24transducers
dependingonthedensityofstructures.
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Groupingthetransducersbythedensityofstructure(solidorlight)andconnectingthemtoa
separateoutputchannelwillallowyoutoadjustthelevelforeachgroupseparately.Forexample,
output“TRANSDUCERS1”canbededicatedtosolidsurfaces(upto10‐12transducers),whilethe
output“TRANSDUCERS2”‐tolightsurfaces(upto24transducers).
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Whentherearemanysolidstructuresintheroom,itmaybenecessarytoinstallmorethan10‐12
"solid"transducers.Inthiscaseitispossibletosharethesecondoutputbetweenthe"light"and
"solid"transducers.Takingintoconsiderationthatthecombinedoutputshouldproduceahigher
powerandlightstructures,beinggoodconductorsofsound,demandalesserportionofnoise,itis
recommendedtochangethestandardconnectionschemesothatthe"light"transducersare
connectedinlongerserialchains.
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Attention:
Resistanceoftheentireloadshouldnotbelowerthan3Ohmper‘TRANSDUCERS’channel.
DamagetoyourDNG‐2300mayoccurifimproperlywired.
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Beforeconnectingtothegenerator,measuretheresistanceoftheentirecircuitwithamultimeter.
Youcanalsocalculatetheresistanceoftheentireloadbyconsideringtheresistancemarkedonthe
transducerandbyusingthefollowingformulas:
ResistanceofaserialcircuitiscalculatedasR=Rt*n,whereRtistheresistanceof
transducerandnisthequantityoftransducers.
Example:resistanceof3transducers(each4Ohm)connectedinseriesis4+4+4=12Ohm
ResistanceofaparallelcircuitiscalculatedasR=1/(1/R1+1/R2…1/Rn)
Example:resistanceof3parallelcircuitseachconsistingof3serial4Ohmtransducersis
R=1/(1/12+1/12+1/12)=1/0.25=4Ohm
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10
Mountingthetransducers
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TheTD2300transducersaresuppliedwithanumberofaccessoriesallowingdifferentmethodsof
installation.Themethodofmountingisselecteddependingonthetypeofsurface.
Directscrew(wood)
Plasticdowel(cement,concrete,bricks)
Wallanchor(bricks,drywall,fragilematerials)
Mountingdisk(windowglass)
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Theaccessoriesformountingonpipesshouldbepurchasedseparately:interlockedhoseclamp100‐
150mm,boltM4x8,washerandnut.
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Itisrecommendedtoreadthemanualsuppliedwiththetransducerbeforestartinginstallation.
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Quantityandarrangementofspeakers
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Behinddroppedceiling‐1xSP2300speakerforeach9‐10squaremeters
Inventilationshafts,airductsandothervoids–1xSP2300foreachvoid
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SincetheSP2300isassembledfrom3parts,eachbeingaseparatespeaker,itispossibletousethe
3individualpartsforsmallervoids.DisassembletheSP2300byremovingthetriangularholder,cut
thecables,placetheseparatespeakerpartswherenecessaryandreconnecttheminseries.
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ConnecttheSP2300speakersinparallelwhenthereis1,2or3pieces.Foralargerquantity
combinespeakersinserialpairs.Youcanconnectupto6pairs(12pcstotal)
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