overdriveincreasesuntil atthe Blackbird is
producingabalancedand robustdistortion.Asthe
Gainis furtherwound-upthepedalwill beginto
produceprogressively moresaturated singing lead
tonesand effortless pinchharmonics.
ClassicToneStack Eachchannelhasit’s own
dedicatedBass,MiddleandTrebletonecontrols.
Thesetone controls arebased on the passivetone
stacks found on the ‘Blackface’ FenderTwinReverb
Amp.Thesetonecontrols areinteractiveandallow
foragreat dealof toneshaping flexibility.
BypassFootswitch enablesselection between
effectified and non-effectified (dry) signal.Silenttrue
bypass switching ensuresthat‘pops’ or‘thumps’ are
kepttoaminimumwhen engaging the effectand
thereis absolutely no loss oftonefromyourguitarto
yourampwhen the effect is disengaged.
ChannelSelectFootswitch enablesselection of
the cleanoroverdrivechannel.
BalancedDirectOut ¼”TRS(stereo)jack socket
allowsconnectionofthe Blackbird tomixing desk,
computersoundcardorexternalaudiocapture
device.This outputis balanced and transformer
isolated,eliminatingearthloopsandreducing hum
toanabsoluteminimum. The Triad Magnetics audio
transformeralsoimpartsit’s owncharacter,further
enhancing andsweeteningthetone.This outputis
driven byadiscreteclass AB amplifiercircuit-
essentially aminiaturised powerampoutputstage.
There’s no substituteforthe soundofarealtube
ampmoving someair,howeverthe directoutputis
usefulforrecordinginvenueswithpoorroom
acoustics orexcessivebackground noise.Reverb,
eq orcabinetimpulseresponsescan be added post
recording toobtainavery realistic approximation of
amiked guitarampinanidealacoustic space.
ExternalSelect ¼”TRS(stereo)jack socket. This
enablesan externalfootswitch(suchasthe Fender
TwinReverbAmp tremolo/reverbfootswitch)tobe
utilised forremoteswitching ofclean/overdrive
channeland‘Classic’/’Creamy’ modes.
Bias toggleswitchselectsbetween3differentbias
operatingpointsforthefirsttube stage on the drive
channel.This tubeis located onthetop-rightofthe
pedalandcan be swapped forotherminiatureB9A
typestomodifythesensitivity,feeland responseof
the drivechannel.The middleposition selects
biasing fora12AU7whichis alowmm(amplification
tube)tube.The up position selectsbiasing forahigh
mm12AX7and inthedownposition selectsbiasing
foramediummm12AY7tube.Thebiasing forthis
position is adjustableviaan internaltrimpot-
unscrewing the six screwson the basepanelofthe
pedalaccessesthis.Rotatingthetrimpotclockwise
increasesthe biasvoltage,‘hot’biasing the firsttube
stage and rotatinganti-clockwise‘cold’biasesthe
tube.This affectsthepre-ampgain,sensitivityand
the tonalresponse.
