Mackie 1642 Musical Toy Instrument User Manual


 
9
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.
3