Peavey Bass MK III Operating Guide

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OPERATING GUlDE

GENERAL DESCRIPTION

The Peavey Mark III Bass amp is the result of many years of field experience, combined with the latest electronic cichitry to produce
what we believe is the finest bass amp on the market today The new Bass utilizes newly engineered Circwtrylrom input to output, greatly
increased dynamic range. equalization (passive and active). coupled With a sixrband graphic equalizer. pre and post gain controls, bUlllrln
variable electronic crossover DDT" compression Circuitry.AUTOM|X, and complete patch panel capability Ourengineers have "brought it
all together in this one compact and powerful unit that represents the ultimate in contemporaryelectronicdeSIgn and packaging in musical
instrument amplifiers The new Bass is powered by our totally new 4008 power module which utilizes eight high voltage ultrartast output
devices bolted to a massrve aluminum heatsmk The 4008 module incorporates Peaveys unique "DDT" (Distortion Detection Technique)
compresston Circuit that senses the onset of clipping and electronicallycompressesthe Signal to avoid overloadolthe power amplifier, thus
producmg the tightest and cleanest mono bass sound pOSSible while minimiZing the danger of speaker blowout at high output levels This
unique compressor has specially computed attack and releasetirnestailored to retain thedynamics ol stringed instruments. An entirely new
series ol colorecoded knobs have been designed lor this and other Mark lll ampliiiers that not only provrde easy function identilication by
color but also teature greatly improved Visibility and touch rndexrng capability

To prowde even greater tleXibility, Peavey has destgned one channel With active EO and parametric middle while the other channel
uses the latest in passwe equalization Our Dulllrln variable electronic crossover is unique in its capability to electronically set the crossover
at any point between 50and 500 Hz thus allowmg biramplitication otthe bass system when utilized with an external poweramplilier/speaker
combination It is generally recognized that bi-amping a bass produces the loudest and most satisfactory results obtainable With this
instrument

The comprehenswe patch panel teaturing both input and output connectors enablesthe Bass to be used with almost any accessory
even those requiring GOO-Ohm impedances The Sixrband graphic equalizer is SwllCh programmable intoeitheror both channels which are
in turn, controlled by ourAUTOMlX remotefootsWitch AUTOMIX enables the user to select either or both channels and LEDs indicate which
channels are active in the AUTOMlX model Our unique pre and post gain controls make posstble total control of level and overall dynamics
lrom each channel. making the AUTOMIX feature even more versatile

Overall, the Mark III Bass is one ol the most electronically sophisticated instrument amplifiers ever made and, in total represents a
quantam tump in instrument amplifier technology

WARNING: To prevent electrical shock or fire hazard, do not expose this
appliance to rain or moisture.

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BASS BLOCK DIAGRAM cnossovm mm:

AMP
INPUT PREAMP Hl
E0 AMP D'V our
V-NW- ? g1 g1 " FREQ
Lo
CH A o o i so ASSIGN 'flD-V OUT
1 _
VTWV 2 BUFFER
ens GAIN POST GAIN iN our NETWORK Am,
"A" ,, LINE AMP
LED LINE
I/'.I V out
GRAPHIC
ATOIX CMPNATlN
U M \- AUTOMlX 0 E s o
v-' CIRCUITRV O 0
REMOTE PREAMP
SWITCH BUFFER _V OUT
Ill AMP POWER
.. i. AMP
8 fl.
LED \\ m
POWER AMP
OUT SFKR
VW INPUT PREAMP ' OUTPUT
on a E0
' g, ? g, g' ASSIGN
0 '3 h - COMPRESSION -
-i 3 e I _
T < I
PRE GAIN m
5 POST emu OUT COMPRESSION
'1 LED

FRONT PANEL
INPUT JACKS 1 AND 2

The Bass features both a high gain (t ) and a low gain (2) {-6 dB) input to enable ittoaccept Signalsolvarying levels and also to taCilitate
usrng two instruments into either channel The high gain (l) input is the one normally used lithe output signal from your instrument or its
assomated electronics is overloading the high gain (1) input, then the low gain {2) input should be used Because olthe unique swttching
circuitry, l and 2 inputs automatically are gain balanced when two instruments are inserted into both inputs

The Bass AUTOMIX function has been recently redeSigned around the latest in analog sWitching circuitry and includes LED activity
indicators to indicate the channels in use (PLEASE NOTE: CHANNEL LEDS ARE lNACTlVE UNTlL AN lNSTRUMENT IS PLUGGED
lNTO THE AUTOMIX JACK)

NOTE!

THE AUTOMIX JACK Is A SPECIAL SWITCHING JACK THAT HAS A DOUBLE DETENT; |.E., TWO POSITIONS. TO

ACHIEVE PROPER OPERATION, THE INPUT PLUG MUST BE INSERTED ALL THE WAY, OR, TO THE SECOND

CLICK. PROPER INSERTION OF THE INSTRUMENT'S INPUT PLUG WILL BE INDICATED BV ILLUMINATION OF

EITHER OR BOTH AUTOMIX LED ACTIVE CHANNEL INDICATORS
AUTOMIX JACK (3)

The AUTOMlX ClICUIIIy was pioneered by Peavey several years ago In order to enable the use at both channels oi the amplifier Itused
to be common to play through onechannel only whilethe otherchannel was not used OurAUTOMlX Circuitryenablesthe playerto utilizethe
full capability of this amplifier by allowmg either or both channels to be used during a pertormance The switching tunction is controlled by
the remote lootswnch which is supplied as standard equipment with the amplitier The AUTOM IX effect is activated when your Input plug is
tully inserted into the AUTOMIX lack and is accompanied by illumination ot one or both LEDs Our Improved Circuitry has prowded post
gain controls lor both channels which are actually master volume controlstor the respectivechannels, enabling sensitivny and dynamics to
be independently adjusted in each channel with the selection at either or both channels accomplished by the AUTOMIX circuitry and its
remote tootswitch

The remote tootswnch teatures a Selector button which enables alternate selection of elttter Channel A or Channel B The
Combiner" button operates to rnix the two channels together and deleat: the Selector button Obwously, when the Cornbiner button lS
activated. both channels are in the circuit as indicated by their LED indicators When in the combined mode the "Selector button is
inoperative Since the combined mode mustlunctlonally overridethe select modetooperate both channels Simultaneously To reactivate the
select mode. depress the "Combiner" button once
PRE GAIN (4)

The pre gain controls determine the amount of gain produced in the input preamp Please understand that this control determines the
sensitivity and not the power output ol the amplitier The control settings in no way can be related to the power theamp is deliveringlothe
speakers because ot a number of other factors such as the input signal amplitude setting of the post gain controls, etc
EQUALIZATION

The equalization Circuitry ofthe Bass is extremelyversatile. as well asreasonably simpleto operate Channel Bieatures the latest active
Circuitry while Channel A is deSigned around somewhat conventional passwe Circunry. Because we have included parametric middle
equalization, some knowledge and operating experience is necessary to obtain maximum benelit lrom this versatile feature
CHANNEL A EQUALIZATION

LOW EQUALIZATION CONTROL (5)

The low equalization control determines the low trequency emphasis and is capable at substantially more ettecl than many olthe more
conventional passwe tonal networks Forthis reason thecontrol will tend to makethe amp sound "bassy at high settings. We have designed
the Circuitryto prowde more tonal variation to allow you a greater range ot variable tonalities

MIDDLE EQUALIZATION CONTROL (6)

The middle equalization control is used to tailor the relative levels ot the Vital mid range frequenCies Experimentation With this middle
control Will show that it is very ellective and enables the "veicing" ot Channel A to be changed signilicanlly because of its advanced Circuit
deston