Boss GT-X - Clean Preamp Summary; Using the Preamps for Overdrive;Distortion


Section14Preamps

©Copyright2000-2002BarryS.Pearceetal.  72
CleanPreampSummary
Insummary,thebestwaytousethepreampsareasabase
for a patch, providing the patch with the basic tone
characteristics, and then use other effects to colour and
shapeasnecessary.AlwaysrememberthattheEQisthere
toalterthecolouring.Examiningthepresetshasshownus
howeffectivethiscanbe.

TheMasterVolumecontrolisinallcasesaflat response
control that provides a good wayof managingthe output
level of the preamp without changing the colour of the
sound.

Lookingatourthreepre-ampswecanseethattheJC-120
gives a fairly well balanced sound, warmer than
nothing/[GT-3]AC.Guitar.TheCleanTwinwithitsboosted
bass,andtreblegivesveryarichwarmsound,andwouldbe
verywellsuitedas a basis for someprettyheavypatches
especiallywithagooddosingofdistortion.Whichpreamp
youchoosewillgreatlyaffecttheunderlyingsoundofthe
patch.Thus,tohelpyouchoosethereisafileinthe'set-
up....' folder called 'GTx-PRE-Compare.jpg'. This image
willgiveyouahandyreferencetochoosingacleanpreamp.

In practice, Bass = Warmth, Middle = Body,
Treble/Presence/Bright = Jangle/Sparkle. For versatility I
love the Clean TWIN. It seems to have more dynamic
controlandrangethantheotherpreamps.It’sverymuchmy
favourite.It’s'Inyourface','Bright'andyetfullofwarmth
andoompf.Itdefinitelytopsthelotoftheminmybook!
UsingthePreampsfor
Overdrive/Distortion
As we have said before, all three clean preamps will
produce overdriven sounds, but they are best suited to
clean. Here the preamps are best suited to
overdriven/distorted sounds. Some of them will give
acceptablecleanresultsbuttheyareprobablybestusedin
theirdistortionmodes,asitwouldbeprettyhardforanyof
thesetobeatCleanTWIN(IMHO).

Well,youmaynowbethinkingthatI'mgoingtogivethe
otherpreampsagoodgoingoveraswell.I'mafraidthatI
amlikelytodisappointhere.Ifeelthathavinglookedatthe
clean preamps youshould, bynow, have a good feel for
howtheampsshapeupwithregardtoalteringsettings.So
whatIhavedoneisbrokenthemdownintofourgroups,and
providedfourimagesinthefilesarea soyoucancontrast
thebasictonecharacteristics.

One thing you will find is that none of the preamps
presented here have a tonal variation as extreme as the
CleanTWIN. Allthesepreampsaremoremodestintheir
tone.

The groups are (along with a short summary of the tonal
characteristics):

[GTx-PRE-CrMaVx.jpg]
Allthesethreeareverysimilar.Allhavea
slight,andImeanslightmidscoop,inthe
100Hz-2kHzregionandaslightboostto
thetrebleendofthingsfrom2kHzup.All
thebassfrequenciesaredroppedoffviaa
highpassfilterfromabout70Hzdown.
Crunch
Ofthesethree,thispreamphasthemost
bassboostinthe40-300Hzarea,however
ithasthesmallesttrebleboostwhichonly
covers2-7kHz.Above7kHzisalowpass
filter dropping off the frequencies down
to 22kHz. In practice this preamp gives
light->heavyoverdriventypesounds.
MATCHDrive
Thisamphastheleastbassofthegroup.
However it has an enhanced treble
compared with the Crunch, but nothing
liketheVOXY.TheTreblehereextends
from2-13kHz before dropping offvia a
low pass filter. The treble boost is at a
similar level to the Crunch. The mids
havethelowestscoopbutonlybyvirtue
of the fact that the bass has been cut
slightly.Againthispreampcangivequite
aheavyoverdrivensound.
VOXYDrive
Thisistheampwiththemosttreble,with
thebooststartingat1.5kHz,boostingthe
treble well above the others before
starting to drop off at 10kHz but not
dropping off sharply until about 15kHz.
BasswisetheVOXYisverymuchmiddle
of the road. In practice this preamp
appears to giveaverymuddyoverdrive,
very similar to the MATCH Drive but
withmorebass.

[GTx-PRE-BlBG.jpg]
Thesetwopreampsshowmorecharacter
thanthe(Ithink)wishy-washyfirstthree.
Herethe mid scoops are deeper, but the
bassandtreblearebalanced.
Blues
Basicwellbalancedpreampwhichhasa
quite deep but broad mid scoop from
90Hz-2.5kHz. The bass is boosted
slightly in the 50-90Hz region, and the
trebleabove2.5kHzisboosted,butdrops
offquicklyafter9kHzreachingthesame
levelastheGT-3/5reference,andtheBG
Lead by 10kHz, and continues to drop
these frequencies off more quickly than