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  4. 400RB-III
  5. Service Manual

Gallien-Krueger 400RB-III Service Manual

Manual is about: bass amplifier

Summary of 400RB-III

  • Page 1

    Service manual 400rb-iii series.

  • Page 2

    Table of contents operating instructions 3 turn on / calibration procedure 20 schematics 21 bill of materials 22 note: as of 1/99, there are no engineering change orders (ecos) for this model. New ecos will be re- leased as they are issued..

  • Page 4: Table  Of Contents

    2 400rb series table of contents gallien-krueger 2240 paragon dr. San jose, ca, 95131 phone: 408-441-7970 fax: 408-441-8085 www.Gallien-krueger.Com introduction..................................................................... Quick start..............................................................

  • Page 5

    3 400rb series congratulations your purchase of a new gallien-krueger 400rb series product is surely the result of much careful consider- ation on your part. For our part, we at gallien- krueger are pleased that you chose us, and are determined that you will be a satisfied customer. In choosing a 40...

  • Page 6

    4 400rb series always listening i have never seen the point in doing things the way others have done them. I also have not been very interested in following the latest fad. I am a stanford educated engineer who worked his way through school as a musician. Like all musicians, i have lugged amplifiers...

  • Page 7

    5 400rb series quick start the 400rb series is designed to be simple to operate. All controls have a well defined purpose and are well behaved. These directions will take you through the basics and give you a good start for setting up your sound. First: set the power switch to off and connect the su...

  • Page 8

    6 400rb series sound tips the 400rb series has several unique features which, if used properly, will obtain that sound you have been searching for. The equalizer: the equalizer is used to fine tune your sound. When adjusting it, do it just a little at a time. These are active circuits, and small cha...

  • Page 9

    7 400rb series safety information verify line voltage and amperage before use: your new 400rb series bass amp has been factory configured for use with: 120 volt/60hz 20 amp circuit for usa & canada. 230 volt/50hz 10 amp circuit for europe & australia. 100 volt/50hz 20 amp circuit for japan. Proper a...

  • Page 10

    8 400rb series . Installation and maintenance installation: to insure proper operation and to avoid potential safety hazards, place the unit on a firm, level surface. When installing the unit in a rack, be sure the mounting hardware can support the amplifier’s weight. To save space in your rack, the...

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    9 400rb series front panel controls 1-balanced direct out: an electronically balanced output, that you can run to your p.A. System. 2-pre/post eq button: selects the direct out signal from before or after the eq. 3-input: a standard ¼” input jack and input attenuator button. The button is generally ...

  • Page 12

    10 400rb series rear panel controls 1- ac receptacle: the power cord is detachable and plugs in here. 2- 240w jacks: 240w power amp output for full-range operation only. They deliver 240 watts into 4 ohms. Lower impedances should not be used. Each jack has a minimum of 8 ohms each. Higher impedances...

  • Page 13

    11 400rb series 400rb series combos the 400rb series combos deliver the 400rb’s unique features and distinct sound by using a variety of internal speaker configurations in compact enclo- sures. Speaker configurations: 400rb/112 one 8 ohm 12 ″ speaker 400rb/115 one 8 ohm 15 ″ speaker the 400rb combo ...

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    12 400rb series tech talk characteristics of the 400rb: the 400rb series is a flexible state-of-the-art bass amplifier, designed to deliver maximum performance and simple operation. This is accomplished through these important features: extremely high current power supply and power amp circuitry, ge...

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    13 400rb series tech talk cool running = reliability: to cool the 400rb we’ve designed a temperature sensi- tive fan cooling system. When the amp is under a light load, the fan is off or running at a low speed, reducing fan noise. As the amp works harder, the fan speed increases to keep everything c...

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    14 400rb series block diagram 400rb series specifications: output power: 240w amplifier 150w @ 8 ohms 240w @ 4 ohms input section: maximum input level 0.6v rms with -10db pad 1.6v rms input impedance 1m ohm send output impedance 220 ohm return input impedance 50k ohm tuner output impedance 10k ohm d...

  • Page 17

    400rbiii bass amplifier turn-on procedure setup: 1. Variac on zero 2. Top cover of amplifier removed (for easy access to the amplifier outputs) 3. Oscilloscope probe (gnd) to chassis ground and (+) to tip of ¼” output jack. 4. Set the volts/div of the oscilloscope to 20v and the time base to 1ms 5. ...

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    6120d.Sch-1 - thu jan 27 07:50:16 2000

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    400rb-iii indented bill of materials 1/26/00-sw note: level 1 refers to main assembly numbers, and level 2 refers to board level components main asssembly numbers are in bold face, while commonly used parts are italicized. Lvl part# description qty ref. Desig. 1 080-0043-a transformer 400rb-iii,120v...

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    Lvl part# description qty ref. Desig. 1 202-0050-a wire assy,26ga,blk,17",2pin 1 1 206-0120-d 400rb-iii,pre amp board assy 1 1 250-0121-d 400rb-iii,power amp module 1 1 602-0007-0 gk warranty card 1 1 gk160-0000 gk safety sheet 1 1 ha202-0004 wire assy,26ga,blk,7",7pin,ul/csa 1 1 ni202-0100 wire ass...

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    Lvl part# description qty ref. Desig. 2 031-3129-0 cap,elec,rad,129,20%,63v 2 c28,29 2 031-3476-0 cap,elec,rad,476,20%,63v 4 c1,2,18,19 2 032-4104-0 cap,pe,104,10%,100v 1 c25 2 032-7104-0 cap,pe,104,20%,250v 2 c31,32 2 034-7103-0 cap,ceramic disk,103,10%,x-250v 1 c30 2 035-8100-0 cap,mica,10pf,5%,50...

  • Page 32

    Lvl part# description qty ref. Desig. 2 060-3742-0 res,metal film,3.74k ohm,1/8w,1% 1 r35 2 060-4322-0 res,metal film,43.2k ohm,1/8w,1% 1 r41 2 060-7501-0 res,metal film,750 ohm,1/8w,1% 1 r24 2 070-0520-0 pot,500 ohm trim,vert 1 r21 2 081-0055-0 inductor,2uh,20a,air core 1 l1 2 091-1001-0 thrm brkr ...

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    Lvl part# description qty ref. Desig. 2 010-1013-0 mpsa56 pnp 80v 500ma to-92 1 q2 2 010-2010-0 j113 n-jfet 35v 2ma to-92 1 q1 2 010-2040-0 j406 dual n-ch jfet 8pin dip 1 q3 2 020-0120-0 1n759a,zener,12v,5%,400mw,do-35 10 d2,3,4,5,10,11,12 2 020-1000-0 1n4148 ,rect-fast,200ma,100v,4ns,do-35 2 d6,7 2...

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    Lvl part# description qty ref. Desig. 2 050-3302-0 res,carbon film,3.3k ohm,1/8w,5% 1 r46 2 050-3303-0 res,carbon film,33k ohm,1/8w,5% 2 r39,67 2 050-3904-0 res,carbon film,390k ohm,1/8w,5% 1 r52 2 050-4701-0 res,carbon film,470 ohm,1/8w,5% 4 r55,57,65,69 2 050-4702-0 res,carbon film,4.7k ohm,1/8w,5...