Owner`s manual

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Owner’s Manual
Owner’s Manual
1. Mic Ins
ThisisafemaleXLRconnectorthatacceptsa
balancedmicorlinelevelinputfromalmostanytype
ofsource.TheseOnyxmicpreampsfeaturehigher
delityandheadroomrivalinganystandalonemic
preamponthemarkettoday.These circuits are
excellentatrejectinghumandnoise.
TheXLRinputsarewiredasfollows:
Pin 1 = Shield or ground
 Pin2=Positive(+orhot)
 Pin3=Negative(–orcold)
Professionalribbon,dynamic,andcondensermicsall
soundexcellentthroughtheseinputs.Themic/line
inputswillhandleanykindoflevelyoucantossat
them,withoutoverloading.
Noteveryinstrumentismadetoconnectdirectlyto
amixer.GuitarscommonlyneedaDirectInjection(DI)
boxtoconnecttothemixer'smicinputs.Theseboxes
convertunbalancedline-levelsignalsfromyourguitar,
intobalancedmic-leveloutputs,andprovidesignaland
impedancematching.Theyalsoletyousendyourgifted
guitarrenditionsoverlongcablesoraudiosnakes,
withminimuminterferenceorhigh-frequencysignal
loss.Askyourdealerorguitarmakerabouttheir
recommendationsforagoodDIbox.
Phantom Power
Mostmodernprofessionalcondensermicsare
equippedforphantompower,whichletsthemixer
sendlow-currentDCvoltagetothemic’selectronics
throughthesamewiresthatcarryaudio.(Semi-pro
condensermicsoftenhavebatteriestoaccomplishthe
samething.)“Phantom”owesitsnametoanabilityto
be“unseen”bydynamicmics(ShureSM57/SM58,for
instance),whichdon’tneedexternalpowerandaren’t
affectedbyitanyway.
The1642VLZ4’sphantompowerisgloballycontrolled
bythephantom[22]switchontherearpanel.
(Thismeansthephantompowerforallchannels
isturnedonandofftogether.)
TheGAINcontrolsforstereochannels9-10and11-12
areonlyusedtoadjusttheMicinputs.Thelineinputs
are set to unity gain.
TheGAINcontrolsforchannels13-14and15-16only
adjusttheline-levelinputs,astheyhavenoMicinputs.
4. Insert
Foundonlyonchannels1–8,theseunbalanced1/4"
jacksareforconnectingserialeffectsprocessorssuch
ascompressors,equalizers,
de-essers,orlters.Theinsertpointisafterthegain
[3]control,butbeforethechannel’sEQ[32],lowcut
[34],fader[25]andmute[30]controls.Insertcables
mustbewiredthusly:
 Tip=send(outputtoeffectsdevice)
Ring = return(inputfromeffectsdevice)
Sleeve = commonground
Eventhoughchannels1–8alreadyhavedirectout[5]
jacks,insertjackscanalsobeusedaschanneldirect
outputs;post-gain,pre-lowcut,andpre-EQ.Seethe
connector section on page 27 showing three ways to use
insert cables.
tip
This plug connects to one of the
mixer’s Channel Insert jacks.
ring
tip
ring
sleeve
SEND to processor
RETURN from processor
(TRS plug)
Neverplugsingle-ended(unbalanced)
microphones,orribbonmicsintothemic
inputjacksifthephantompowerison.
Donotpluginstrumentoutputsintothe
micinputjackswithphantompoweron
unlessyouknowforcertainitissafetodoso.
2. Line Ins
These1/4"jackssharecircuitry(butnotphantom
power)withthemicpreamps,andcanbedrivenby
balancedorunbalancedsourcesatalmostanylevel.
Youcanusetheseinputsforvirtuallyanysignalyou’ll
comeacross,frominstrumentlevelsaslowas–50dBto
operatinglevelsof–10dBVto+4dBu,asthereis45dB
ofgainavailableviathegain[3]knob.Notethat
channels1-8lineinputsareintiallyattenuatedby
15dB.Alwaysmakesuretoperformthelevelsetting
procedureonpage5.
Tolearnhowsignalsareroutedfromtheseinputs,
see the details lovingly described in the channel strip
section.
Toconnectbalancedlinestotheseinputs,use
a1⁄4"Tip-Ring-Sleeve(TRS)plug,wiredasfollows:
 Tip=Positive(+orhot)
 Ring=Negative(–orcold)
Sleeve = Shield or ground
Toconnectunbalancedlinestotheseinputs,
usea1⁄4"mono(TS)phoneplug,wiredasfollows:
 Tip=Positive(+orhot)
Sleeve = Shield or ground
3. Gain
Thesecontrolsarenotinthepatchbay,but
theyarethetoprowofknobsinthechannelstrip
section.(Theyaresovitallylinkedwiththeinputs,
thisseemedlikeagoodplacetodescribethem.)
Ifyouhaven’talready,pleasereadthelevel-setting
procedureonpage5.
Gainadjuststheinputsensitivityof
themicandlineinputs.Thisallows
signalsfromtheoutsideworldtobe
adjustedtooptimalinternaloperating
levels.
IfthesignaloriginatesthroughtheXLRjack,there
willbe0dBofgainwiththeknobfullydown,ramping
to60dBofgainfullyup.
Throughthe1⁄4"input,thereis20dBofattenuation
fullydownand40dBofgainfullyup,witha“U”(unity
gain)markat10:00.This20dBofattenuationcanbe
veryhandywhenyouareinsertingaveryhotsignal,or
whenyouwanttoaddalotofEQgain,orboth.Without
this“virtualpad,”thisscenariomightleadtochannel
clipping.
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