’65 P-REVERB 15W

A S S E M B LY I N S T R U C T I O N SWith loads of helpful tips!

’65 P-REVERB 15W C O M B O A M P K I T ORIGINAL AA1164 CIRCUIT

Sparkling bright,perfect for the surf.

stewmac.com 2 © 2018 StewMac

Contents

About this iconic amp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Parts list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Tools and supplies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Amp voltages are seriously dangerous! . . . . . . . . . . . . . . . . . . . . . . . . . . 6

How to use a snuffer stick . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

How to read resistor values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Capacitor values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Prepping the cabinet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Prepping the eyelet boards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Tips for great soldering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Installing the chassis-mounted components . . . . . . . . . . . . . . . . . . . 13

Wrapping parts onto the bias board . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Wrapping parts onto the main board . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Installing and soldering the boards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Installing the fuse, lamp, and knobs . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Testing and troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Final assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Tips for using this amp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Learning more: secrets revealed in the schematic . . . . . . . . . . . . . . 46

AA1164 circuit schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

More iconic amp kits from StewMac . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

AA1164 wiring diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Tube replacement chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

COPYRIGHT WARNINGThis material is protected by copyright and has been created by and solely for the purposes of StewMac . You may not sell, alter or further reproduce any part of this material, or distribute it to any other per-son . Where provided to you in electronic format, you may only print from it for your own private use . Failure to comply with the terms of this warning exposes you to legal action for copyright infringement .

How to build this kit!


Iconic American tone is now in your hands

Be excited!Your new StewMac ’65 P-Reverb will be a blast to play through and even more fun to build .

Plug your single-coils straight in and use its signature clean tone, or go surfing with the onboard effects .

This amp is an ICONThe smallest member of the black-panel family to offer both reverb and tremolo, this amp made its name as a jangly pop dream machine . Aficionados treasure its early low-end breakup powered by a pair of 6V6 power tubes .

Suggested listening while you build this kit: the Beach Boys’ “Surfin’ USA” and the great sounds of Ryan Adams .

StewMac ICON KITS bring classics that are no longer made, or are simply unaffordable, within reach . And the best part is you get to build them with your own hands .

We give painstaking attention to parts selection, authentic materials, and instantly recognizable details—everything that makes the originals so sought after .

Build it with StewMacThese immersive instructions walk you through every step of creating your P-Reverb . And you’ll learn a lot, gaining a deep knowledge of your amp’s inner workings .

Follow our steps closely for safety, too: we’ve carefully laid out a path that even newcomers can follow in handling electrical components .

Building an amp can seem daunting, but nobody makes it easier than StewMac . Watch for helpful tips along the way, too—we’re here to help!

Let’s get building!

’65 P-REVERB 15W CO MB O AMP KIT ORIGINAL AA1164 CIRCUIT


Here’s how to build this amp!

See page 20

Wiring goes like this:1. First, you’ll wrap the leads, connecting them without solder. 2. Then double-check all the connections. Don’t rush!3. When everything checks out, it's time to solder. The numbered steps tell you when.

Get the cabinet ready, starting at Step 1 on page 8.You’ll prep the metal chassis and the eyelet board too.

Learn more:You don’t need to read the schematic, but it’s fun! See how your guitar’s signal gets processed into sound on page 46.

Sort your components by type, using the parts list.Quick look:

#10734 © 2018 StewMac

’65 P-REVERB 15WORIGINAL AA1164 CIRCUIT

GroundJackTransformer Preamp tube

plategrid

cathode

Power tube

grid

plate

cathode

screen

Capacitor Electrolytic Cap. DiodeResistor Potentiometers Rectifier tube

plate cathodefilamentplate

Shieldedcable

Gain GainGainProcessing Processing

ProcessingProcessing

Output

Power

Processing

Negative Feedback

68K

250K

A25

0KA

25μF

50V

25μF

50V

25μF

50V

25μF

50V

1.5K

100K68

K

1M

40μF

500V

20μF

500V

20μF

500V

20μF

500V

BB

D B

.1μF

22K 100μF

100V

2

2

1+160V

+160V

6

3+1.3V

8+1.3V

+160V

6

8+1.2V

+200V

6

8+50V

7

25μF

50V

25μF

50V

1.5K 1.

5K

100K

250pF

+240V +240V

100K

3MRASpeed

+320V

Vibratopedal

Reverbpedal

Reve

rb10

0KL

Reverb unitOutputInput

15K-2W 15K-2W

1K-1W

.1μF.022μF .022μF

SOCKET V1

7025

SOCKET V2

12AT7

SOCKET V7

GZ34

SOCKET V6

6V6 GT

SOCKET V4

12AX7

SOCKET V5

6V6 GTSOCKET V3

12AX7.1μF

.1μF

.01μF

500pF

3.3M

2700

10pF

.047μF

1

100K

TREB

LE

VOLU

ME

BASS

6.8 K

1MA

77

5 ExtensionSpeaker

TR2

TR3

TR1

TR1: 125P1BTR2: 125A10B TR3: 125A20B

8

8

5

6 8

4 2

3 +2.4V

23

3 +1.2V

+160V1

2

1

72

4+400V

+400V 6

8+8.0V

+400V4

3 +410V

3 +410V

+49V

100K

47Ω

56K

1K

-34V

220K +

420V

220K

1M

1M

1M 220K

2.2K1M

100K

470K

.033

μF

+42

0V

.02μ

F

.02μ

F

.01μ

F

56K

1M

+260V +250KLIntensity

100K

340VACAC switch

1 ampslow-blow fuse

To tube heaters and pilot light

340VAC

3.3K

220K

1.5K

OutputGain Processing


A magnifierhelps!

Capacitors and diode

r (1) 250pF 500V silver mica

r (1) 500pF 500V silver mica

r (1) .0033μF 600V Orange Drop




r (1) 10pF 500V ceramic disk

r (2) .01μF 500V ceramic disk

r (1) .02μF 500V ceramic disk

r (6) 25μF 50V Sprague Atom

r (1) 100μF 100V aluminum electrolytic

r (1) 40μF/20μF/20μF/20μF 500V filter cap

r (1) 1N4007 1000V rectifier diode

510K

332J 600V

223J 600V

473J 600V

104J 600V

+

25µF

100μf

500V

Resistors

r (1) 47Ω .5W carbon composite

r (2) 100Ω .5W carbon composite

r (1) 1K .5W carbon composite

r (4) 1.5K .5W carbon composite











r (6) 1M .5W carbon composite

r (1) 3.3M .5W carbon composite

r (1) 1K 2W metal oxide

r (2) 15K 2W metal oxide

Yellow Violet Black Gold

Brown Black Brown Gold

Brown Black Red Gold

Brown Green Red Gold

Red Red Red Gold

Red Violet Red Gold

Orange Orange Red Gold

Blue Gray Red Gold

Red Red Orange Gold

Green Blue Orange Gold

Blue Gray Orange Gold

Brown Black Yellow Gold

Red Red Yellow Gold

Yellow Violet Yellow Gold

Brown Black Green Gold

Orange Orange Green Gold

Brown Black Red Gold

Brown Green Orange Gold

Hardware

r (6) 8-32 machine screw, 3/8"r (10) 8-32 locknut

r (6) 6-32 machine screw, 1/2"r (6) 6-32 locknut

r (6) 4-40 machine screw, 3/8"r (8) 4-40 machine screw, 1/4"r (14) 4-40 locknut

r (2) Chassis mounting strapr (4) Chassis strap screw and nut

r (6) Rubber grommet

r (1) Strain relief for power cord

r (1) Filter cap mounting clamp

r (1) Cabinet

r (1) 10” speaker

r (1) Chassis

r (1) Cable clamp

r (1) Screw for cable clamp

r (1) Faceplate/backplate set

r (2) Eyelet boards set

r (2) Insulator boards set

103K

203Z

Parts list


r (1) Speaker plug

r (4) RCA-style jack

r (3) Three-lug shorting jack

r (1) Two-lug mono jack

r (4) Nine-pin tube socket

r (4) Shield for nine-pin socket

r (3) Eight-pin tube socket

r (3) Tension clip for 8-pin socket

r (3) 12AX7 preamp tube (also called ECC83S)

r (1) 12AT7 preamp tube (also called ECC81)

r (2) 6V6S power tube

r (1) 5AR4 rectifier tube (also called GZ34)

r (1) Fuse socket

r (1) Fuse (1 amp, slow blow)

r (1) Pilot lamp socket with lens

r (1) Pilot lamp bulb (#47)

Transformers

r (1) Power transformer

r (1) Output transformer

r (1) Reverb driver

4

3 2

18

76

5

12AT712A

X7

6V6

5AR

4

6

4 3 21

987

5

r (2) 250K control pot (A–audio taper)

r (1) 1M control pot (A–audio taper)

r (1) 3M control pot (RA–reverse audio taper)

r (1) 100K control pot (L–linear taper)

r (1) 250K control pot (L–linear taper)

r (6) Knob

r (2) Three-lug terminal strip

r (1) Power switch (2 lugs)

r (1) Ground switch (3 lugs)

r (1) Power cord

Reverb

r (1) Reverb tank

r (1) Reverb tank bag

r (1) Reverb wiring kit

r (1) Reverb footswitch

Wire

r (1) White wire

r (1) Green wire

r (1) Speaker wire (two leads)

1234

10

56

7 8 9

250KA

1MA

3MRA

100KL

250KL

Parts list

Vintage-style push-back wire lets you push the insulation back instead of cutting it away. BUT: Trimming the insulation still works better.


#0531 StewMac Solder Monster

#3000 Guitar Tech Screwdriver Set

#1606 Wire Stripper

#1607 Wire Cutter

#0501 Solomon SL-30 Soldering Station

#1609 Round Nose Bending Pliers #0505

Kester Pocket-Pak Solder

StewMac’s Solder Monster holds parts while you solder

Tools and supplies

Required Phillips screwdrivers, #1 and #2 Item #3000 Guitar Tech Screwdriver Set

Needle nose pliers Item #1610 Long Nose Pliers

Wire cutter Item #1607 Wire Cutter

Wire stripper Item #1606 Wire Stripper

Soldering iron (preferably 40W) Item #0501 Solomon SL-30 Soldering Station

Solder (at least one Pocket-Pak) Item #0505 Kester Pocket-Pak Solder

Solder sucker Item #0503 Solomon Solder Sucker

Drill with a 5/32" bit For mounting eyelet board and filter cap

Ruler Item #4905 StewMac Shop Rule

Digital multimeter Item #3618 Fieldpiece Pocket Multimeter

Snuffer stick (bleed resistor) Item #1552 Snuffer Stick

Copper shielding tape Item #0028 2" Conductive Copper Tape

Pencil Colored art markers Wooden chopsticks Glue Wood glue, white glue or contact cement for gluing a paper label inside the cabinet

Helpful Round nose bending pliers Item #1609 Round Nose Bending Pliers

Solder wick Item #0504 Solder Wick, 5-foot roll

Soldering aids Item #0521 StewMac Soldering Aids

Soldering stand Item #0506 Solomon Soldering Stand

Solder Monster, or helping hand tool Item #0531 StewMac Solder Monster

Chassis stand Item #10750 Chassis Stand

Printed circuit board vise Scratch awl or center punch Item #3000 Guitar Tech Screwdriver Set

Tray for loose parts


High voltage, even when unpluggedWhen you turn on an amp, the capacitors are designed to take on a charge and hold it . That stored voltage is enough to injure you seriously, or even kill you .

These components aren’t a threat until the first time you plug the amp in . The stored electricity can be safely discharged to ground with a snuffer stick . See how to use it below .

Once your amp has been turned on, don’t touch the wiring with your bare hands—even after turning it off . If you need to press on a contact, use a chopstick or Sharpie marker, which are both non-conductive . Don’t use a pencil, because graphite is conductive .

It’s important that you understand the dangers so you’re working safely . Here’s how to do it right .

Wear rubber-soled shoesRubber soles increase the insulation between yourself and the ground .

Take off your ringA metal ring on your finger can bridge a hot connection to ground .

Wear safety glassesRosin-core solder sometimes bubbles up, and it can spew molten specks into the air . You don’t want molten solder in your eyes .

It’s better not to work aloneElectrical shocks can incapacitate you, and having someone available to call 911 can be a lifesaver .

How to use a snuffer stickTo discharge a capacitor, clip the snuffer stick lead to ground—preferably a mounting bolt on the power transformer . Hold the tip of the stick to the cap’s positive lead and use your multimeter to watch the voltage drain to less than 18V .

Take breaks and stop when you’re tiredFatigue leads to mistakes, and no one can afford mistakes when working with electricity .

Stay suspiciousWhether it’s the first time you’ve been inside a live ampli-fier or the 100th time, don’t become complacent . If you discharge the caps and walk away for a few minutes, check again for residual voltage when you return . Capacitors can self-charge through a phenomenon known as dielectric memory .

Check before powering on It’s easy to forget that you a left a stray tool or wire in the chassis . It’s also easy to forget to re-attach the speaker wire, and that can fry an output transformer in seconds . Constant vigilance is your friend when working on amps .

Always unplug itUnplug the amp whenever you don’t specifically need it plugged in . Some points are always hot when the amp’s plugged in, even if the power switch is off . These points include the lugs on the fuse socket, power switch, and standby switch .

Amp voltages are seriously dangerous!

Professionals who work on amps take these safety habits very seriously


A resistor’s value—the amount of resistance it creates—is rated in ohms (Ω) . Larger ohm values mean more resistance . For example, a 100Ω resistor creates ten times as much re-sistance as a 10Ω resistor .

The resistors used in amplifiers are too small to have value numbers printed on them . Instead, a system of colored bands tells their values . The key to reading these bands is provided below . However, an easier way to decode these bands is to download one of the many smartphone apps for this purpose .

One band will be the nearest to an end of the resistor . That band tells the first value . Combine it with the value of band 2 to get a two-digit number (68 in our example below) . Multiply that number by band 3 (68 x 1,000 = 68,000) . Thou-sands are represented by the letter K, so this resistor is 68K (kilo-ohms, or KΩ) .

If there is a fourth band, it will be either silver or gold . This indicates the tolerance allowed during manufacturing . The resistors used in this kit have a +/- 5% tolerance, represented by a gold band 4 .

A magnifying glass helps a lot . The bands on a 470Ω resistor are yellow/violet/brown, and the bands on a 47K resistor are yellow/violet/orange . They’re easily confused!

Can’t read the colors?You can always use a multimeter to test a resistor’s value . Set your meter to ohms and connect the test leads on each side of the resistor .

Capacitor values are typically printed on the component . The key values with caps are their capacitance and voltage .

Think of a capacitor as a container that can hold electricity . Capacitance, measured in farads, refers to how much elec-tricity this container can hold—its capacity . One farad (1F) would be much too large for use in an amplifier . Caps for amps are rated in millionths of a farad, called microfarads (μF), or trillionths of a farad: picofarads (pF) . The voltage spec for a cap refers to how much DC voltage it can handle at any given time .

A unique property of capacitors is that they don’t allow DC current to flow past them, only AC current . This is important in parts of an amplifier circuit, such as the path between a preamp stage and a power amp stage . Here, a “coupling capacitor” will block DC voltage, allowing only the AC guitar signal to pass .

Filter capsCapacitors also filter out 60Hz hum, or “ripple,” after the AC current from the wall is converted to DC . These capacitors are called filter caps, because they filter out the ripple from a power supply . The filter caps in this amp are the 8μF and 16μF electrolytic capacitors .

Electrolytic capsElectrolytic capacitors contain electrolyte: a liquid or gel that gives them a large storage capacity . Electrolytic caps are typically polarized .

Polarized capsSome capacitors have polarity and some don’t . It’s extremely important to install polarized caps correctly in a circuit . The positive lead of an electrolytic cap will be indicated by an indented ring around one edge of the capacitor . The nega-tive lead will often be indicated by a band of arrows pointing to the negative lead .

Installing capacitors with the polarity backwards will make the circuit malfunction and quickly destroy the capacitor—even causing it to explode .

Band 1 Band 2 Band 3 Band 4 1st Digit 2nd Digit Multiplier Tolerance

6 8 x1,000 +/- 5%

68K +/- 5%K = 1,000

Blue

Read this band first (closest to an end)

Gray Orange Gold

BLACK 0 0 1 None +/- 20%

BROWN 1 1 10

RED 2 2 100

ORANGE 3 3 1,000

YELLOW 4 4 10,000

GREEN 5 5 100,000

BLUE 6 6 1,000,000

VIOLET 7 7

GRAY 8 8 0.01 +/- 10% SILVER

WHITE 9 9 0.1 +/- 5% GOLD

NegativePositive

+ 25μF

8μf

How to read resistor values Capacitor values


STEP 3

Solder the speaker leadsTwist the speaker leads together to keep them neat .

Push the insulation back 3/8" and in-sert the white lead into the speaker’s positive terminal and the black lead into the negative terminal .

Before soldering these leads, place a business card or other protection under the terminals to prevent sol-der dripping onto the speaker cone . Solder the two leads to the speaker terminals .

Prepare the cabinet for mounting the amp chassis by first removing the two back panels .

STEP 1

Mount the power cord clampDrill a 5/64" pilot hole to mount the nylon cable clamp . Locate the clamp inside the left wall of the cabinet, 8" up from the bottom and 1" in from the panel mounting ledge .

Don’t drill through the cabinet! Use a piece of masking tape on your drill bit to mark the depth, or use a StewMac Depth-stop Drill Bit (item #1712) .

Use the black cable clamp screw to mount the clamp . You’ll secure the power cord with this clamp later, after the testing .

Start by prepping the cabinet

Check off eachcompleted step

STEP 2

Solder the speaker plugUse a small screwdriver to remove the back of the speaker plug .

On the black and white speaker leads, push the insulation back 3/8" . Solder the white positive lead to the tip lug (center of the plug) .

Trim the black lead and solder it to the sleeve lug . The solder joints need to be neat so they won’t short against the metal case . See “Tips for great soldering” on page 11 .

Reassemble the plug and do a con-tinuity test with your multimeter to make sure there’s no connection between the plug’s tip and its metal case (see page 43) .

Back

Here


’65 P-REVERB 15WO R I G I N A L AA1 1 64 C I R C U I T

StewMac®

I C O N K I T S

Use only 1-amp slow-blow fuse.

DANGER: Unplug the amp before changing tubes.Tube locations from left to right:

5AR4(GZ34)

6V6 6V612AT7(ECC81)

12AX7(ECC83)

V7 V6 V5 V2 V1

12AX7(ECC83)

12AX7(ECC83)

V4 V3

#10734

STEP 7

Solder four RCA plugsThe shielded wire is in two 3-foot lengths . At the ends of each piece, pull 3/4" of the wire mesh shielding away to one side and strip away 3/8" of the internal cloth shielding . Insert the exposed wire into an RCA plug so that it reaches the tip of the center post .

Solder this lead in place at the tip of the plug . Don’t leave solder on the outside of the plug tip which would keep it from fitting into the jack . See “Tips for great soldering” on page 11 .

After the plug tip cools and the inside solder joint is set, solder the braided wire shielding onto the outside of the plug . Solder the four RCA plugs this way, on each end of the two cables .

These two cables will connect the reverb tank .

Test for continuity between the tips of the plugs on each cable, then test for continuity between the shields of the plugs in the same way .

Also test to make sure you don’t have continuity between the tip and the shield of each plug, which would indicate a short in the jumper . If your multimeter finds unwanted continu-ity, the likely culprit is the inside (tip) wire shorting to the outer shield . If that happens, de-solder the tip con-nection and redo that solder joint .

STEP 5

Install the faceplate + backplateSecure the faceplate by putting the Volume and Bass control pots in their holes and sliding the faceplate over them . Install washers and nuts on the pots to hold the plate in place .

Use the 1MA pot for Volume and a 250KA pot for Bass . Install them with their lugs facing up for soldering . See the wiring diagram on Page 12 .

Install the backplate the same way, using the 2-lug extension speaker jack and the 3-lug ground switch .

This switch is just for looks, because ground switches are not needed in modern amps with 3-wire grounding power cords . But having it there keeps the vintage 1960s look .

Mount the ground switch so it toggles left/right rather than up/down .

STEP 6

Glue the tube placement chart

Cut out the tube replacement chart on page 51 . Put a thin coat of glue or contact cement on the back and glue it to the inside wall of the cabinet .

STEP 4

Install the speakerRemove the nuts from the four speaker mounting screws . Carefully slide the speaker onto the mounting screws until it’s flush with the front panel .

Install the mounting nuts so they lightly touch the speaker frame .

Do not tighten the nuts in a circular pattern around the speaker, because this can warp the speaker frame .

Instead tighten one nut with a quarter turn so it’s just snug, then do the same to the opposite side . Then snug the third nut and fourth . Repeat this criss-cross pattern of quarter-turns until all four nuts have had one full turn . This will give proper tension to compress the speaker gasket . Overtightening can damage the cone and cause un-wanted distortion .

Criss-cross tightening prevents warping.


This circuit is built on two eyelet boards: the large main board and a smaller one called the bias board . For each of these, there’s an additional blank insulator board of the same size .

These insulators mount behind the eyelet boards to prevent the com-ponents from contacting the metal chassis .

Each pair of boards will mount to the chassis with two machine screws . The first step in preparing these boards is to drill mounting holes through the blank insulators .

Prepping the eyelet boards

STEP 8

Drill the insulator boardsNoting the eyelet holes, orient the boards as shown above . Align each eyelet board with its insulator and tape them together .

The mounting holes are pre-drilled in the main eyelet board, but not in its insulator board . Drill through the holes indicated using a 5/32" drill bit . Separate the boards and set the insulator board aside for later .

The smaller bias board does not have pre-drilled mounting holes . Place it in the chassis as shown . Holding the board in position, turn the chassis over to see the mounting holes .

With a sharp pencil, mark the two hole locations onto the insulator board . Drill two 5/32" mounting holes through this pair of boards . Set the insulator board aside for later .

You'll drill the mounting holes in the bias board. In the main board, they're already drilled.Insulator


STEP 9

Number the eyelets and holesThese instructions will refer to the eyelets and holes on the main eyelet board by number and the bias board by letter . Use a pencil to mark these numbers and letters onto the boards .

STEP 10

Prep one grounding stripWith a wire cutter, snip the mounting holes on a 3-lug terminal strips as pictured . Cut a 1" piece of green wire and remove the insulation . Wrap and solder the wire across the terminals, electrically connecting all three lugs . This will be used as a grounding strip .

Snip

Wrap

Solder

1 53 4

2

10

59

20176 7 8 9 11

5857565554

60 61 62 63 64 6568 69 70

71

72

73

7466 67

1213

14 15 1618 19 21

2425 26

273029

28 31

22 2332 33 34 35

37 40 41 42

43 4445 46 47 48 49 50

51 525338

39

36

A B CD

EF

Tips for great soldering!n Wrap the leads tightly for a good electrical contact before soldering . Don’t use solder to “glue” loose joints .

n Melt a small amount of solder onto the tip of the iron (“tinning” the iron) . Hold the tip against the connection until the connection reaches solder-ing temperature . This should take just a few seconds .

Also tin component leads like multi-strand wires to help the solder flow for a better joint .

n Keep your soldering tip clean by wiping it often on a damp sponge . And keep it tinned by occasionally melting a little solder onto it .

n Feed solder to the connection, not to the iron . Stop feeding solder once an eyelet is filled . Keep the iron on the connection for a second longer to allow time for all of the flux to cook out of the joint .

n Don’t ever blow on the hot solder, or touch anything until the joint is completely cool . A good solder joint is shiny—a sign that it was left to cool undisturbed .

n After the joint has cooled, trim away the excess wires .

n Plan ahead so each joint is only soldered once . Resoldered joints are messy and more likely to fail .

n Position the parts so their specs face out so you can read them later . Many builders also align resistor bands to read in the same direction .

n How much insulation to strip? With plastic insulation, strip 3/8" from the wire ends . Push-back wire works best when you strip away about 1/4" of the cloth wrap .

You’re ready to build!

stew

mac

.co

m

12

©20

18 S

tew

Mac

VIB

RAT

OPE

DA

LRE

VER

BPE

DA

LRE

VER

BO

UTP

UT

REV

ERB

INPU

TSP

EAK

ERPO

WER

GRO

UN

DFU

SEEX

TEN

SIO

N

PILO

TLA

MP

V7

5AR4

V6

6V6

V5

6V6

V4

12A

X7

V3

12A

X7

V2

12AT

7V

112

AX

7

INTE

NSI

TYSP

EED

REV

ERB

BA

SSTR

EBLE

VO

LUM

EIN

STRU

MEN

TS

21

POW

ERTR

AN

SFO

RMER

FILT

ER C

AP

OUTPUT TRANSFORMER(mounted outside)

REVERB DRIVER(mounted outside)

4 3

21

87

65

4 3

21

87

65

4 3

21

87

65

6

4321

98 7 5

6

4321

98 7 5

6

4321

98 7 5

6

4321

98 7 5

O

–

U

X

Y

250KA

1MA

stew

mac

.co

m

13

©20

18 S

tew

Mac

Inst

alli

ng

th

e ch

assi

s-m

ou

nte

d c

om

po

nen

ts

S

TE

P 1

1

Mo

un

t th

e p

ow

er t

ran

sfo

rmer

an

d t

wo

3-l

ug

ter

min

al s

trip

sTh

e p

ower

tra

nsfo

rmer

has

nin

e le

ads

colo

r-co

ded

in fo

ur p

airs

, plu

s a si

ngle

red/

yello

w s

trip

ed le

ad . T

wis

t the

sam

e-co

lor

pai

rs to

geth

er . F

eed

all t

he le

ads

into

the

chas

sis

thro

ugh

the

squa

re h

ole .

Inst

all

the

tran

sfo

rmer

on

th

e o

uts

ide

of t

he c

hass

is, u

sing

fou

r 8-

32 lo

cknu

ts

insi

de .

Mo

un

t th

e tw

o t

erm

inal

str

ips

und

er th

e lo

cknu

ts a

t the

fron

t and

bac

k co

rner

s as

sho

wn:

the

one

you’

ve tu

rned

in

to a

gro

undi

ng s

trip

goe

s to

the

fron

t .

S

TE

P 1

2

Inst

all t

hre

e ru

bb

er g

rom

met

sSq

uee

ze t

hes

e in

to t

he

thre

e h

ole

s as

sh

own .

The

se g

rom

met

s p

rovi

de

stra

in

relie

f fo

r th

e tr

ansf

orm

er w

ires

that

will

p

ass

thro

ugh

the

met

al c

hass

is .

S

TE

P 1

3

Mo

un

t th

e o

utp

ut

tran

sfo

rmer

The

ou

tpu

t tr

ansf

orm

er h

as r

ed, b

lue,

br

own,

bla

ck, a

nd g

reen

lead

s . T

hrea

d th

e re

d, b

lue

and

bro

wn

lead

s th

roug

h th

e le

ft r

ubb

er g

rom

met

as

pic

ture

d in

the

di

agra

m, a

nd t

he b

lack

and

gre

en le

ads

thro

ugh

the

mid

dle

grom

met

.

Usi

ng

tw

o 8

-32

mac

hin

e sc

rew

s an

d lo

cknu

ts, m

ount

the

tra

nsfo

rmer

to

the

outs

ide

of th

e ch

assi

s .

S

TE

P 14

Mo

un

t th

e re

verb

dri

ver

The

reve

rb d

rive

r is

a t

rans

form

er w

ith

red,

blu

e, g

reen

, and

bla

ck le

ads .

Thr

ead

thes

e fo

ur le

ads

thro

ugh

the

rem

aini

ng

rub

ber

gro

mm

et .

Use

tw

o 8-

32 x

1/4

" m

achi

ne s

crew

s to

m

ount

the

rev

erb

driv

er o

n th

e ou

tsid

e of

the

chas

sis .

S

TE

P 1

5

Mo

un

t th

e fi

lter

cap

acit

or

The

larg

e fil

ter c

ap m

ount

s to

the

chas

sis

with

the

filte

r cap

acito

r mou

ntin

g cl

amp .

Th

e cl

amp

att

ache

s to

the

end

of c

apac

i-to

r nea

r the

lugs

, and

then

mou

nts t

o th

e ch

assi

s us

ing

6-32

x 1

/2" m

achi

ne s

crew

s an

d lo

cknu

t . If

need

ed, e

nlar

ge th

e sc

rew

ho

les

by d

rillin

g th

em w

ith a

5/3

2" b

it .

Att

ach

the

clam

p s

o th

at t

he c

apac

itor’s

ne

gativ

e lu

g (m

arke

d “–

”) is

clo

sest

to th

e p

ower

tran

sfor

mer

, as

show

n .

S

TE

P 1

6

Inst

all t

he

spea

ker

ou

tpu

t ja

ckA

dd

the

3-lu

g sp

eake

r ou

tput

jack

nex

t to

the

2-lu

g ex

tens

ion

spea

ker j

ack

whi

ch

you’

ve a

lread

y in

stal

led

.

Thes

e ja

cks

are

elec

tric

ally

gro

un

ded

th

roug

h co

ntac

t w

ith t

he m

etal

cha

ssis

, so

tigh

ten

them

wel

l for

a g

ood

grou

nd .

S

TE

P 1

7

Inst

all t

he

thre

e la

rge

tub

e so

cket

s w

ith

ten

sio

n c

lip

sO

rient

the

se 8

-pin

tub

e so

cket

s so

tha

t p

in 1

is c

lose

st t

o th

e re

ar p

anel

of

the

chas

sis .

Use

4-4

0 x

3/8"

mac

hine

scre

ws t

o m

ount

th

ese

sock

ets

on th

e ou

tsid

e of

the

chas

-si

s . In

clud

e a

tens

ion

clip

on

top

of e

ach

sock

et to

pro

vide

sup

por

t for

thes

e th

ree

tub

es w

hen

they

’re in

stal

led

late

r .

S

TE

P 1

8

Inst

all t

he

fou

r sm

all t

ub

e so

cket

sU

se t

wo

4-40

x 1

/4"

mac

hine

scr

ews

to

mou

nt th

e fo

ur re

mai

ning

tub

e so

cket

s .

Posi

tion

thes

e so

cket

s so

pin

3 is

clo

sest

to

the

rear

pan

el o

f the

cha

ssis

.

S

TE

P 19

Inst

all t

he

fuse

so

cket

Mo

un

t th

e fu

se s

ock

et s

o i

ts s

ide

lug

face

s th

e op

en s

ide

of t

he c

hass

is . T

his

orie

ntat

ion

mak

es it

eas

ier t

o so

lder

late

r .

S

TE

P 2

0

Inst

all t

he

po

wer

sw

itch

Mou

nt th

e p

ower

switc

h w

ith it

s tw

o lu

gs

faci

ng u

p fo

r sol

der

ing

late

r .

S

TE

P 2

1

Inst

all t

he

fou

r R

CA

jack

sM

ount

the

RC

A ja

cks

to t

he c

hass

is w

ith

the

larg

e w

ashe

rs o

n th

e ou

tsid

e . O

nce

in-

stal

led,

ben

d th

e gr

ound

ing

tab

s sl

ight

ly

away

from

the

insi

de

of th

e ch

assi

s .

S

TE

P 2

2

Inst

all t

he

pil

ot

lam

p s

ock

etM

ount

the

soc

ket

by s

crew

ing

the

lens

fr

om

th

e o

uts

ide

into

th

e so

cket

as-

sem

bly

. Pos

itio

n th

e so

cket

so

the

arm

su

pp

ortin

g th

e la

mp

fac

es t

he s

ide

wal

l of

the

chas

sis .

Som

e am

p b

uild

ers a

dd

a dr

op o

f glu

e to

th

e m

ount

ing

thre

ads

to k

eep

vib

ratio

ns

from

loos

enin

g th

e so

cket

from

hig

h-vo

l-um

e p

layi

ng .

stew

mac

.co

m

14

©20

18 S

tew

Mac

VIB

RAT

OPE

DA

LRE

VER

BPE

DA

LRE

VER

BO

UTP

UT

REV

ERB

INPU

TSP

EAK

ERPO

WER

GRO

UN

DFU

SEEX

TEN

SIO

N

PILO

TLA

MP

V7

5AR4

V6

6V6

V5

6V6

V4

12A

X7

V3

12A

X7

V2

12AT

7V

112

AX

7

INTE

NSI

TYSP

EED

REV

ERB

BA

SSTR

EBLE

VO

LUM

EIN

STRU

MEN

TS

21

4 3

21

87

65

4 3

21

87

65

4 3

21

87

65

6

4321

98 7 5

6

4321

98 7 5

6

4321

98 7 5

6

4321

98 7 5

OU

X

Y

O

–

U

X

Y

250KA

250KA

1MA

3MRA

100KL

250KL

stew

mac

.co

m

15

©20

18 S

tew

Mac

S

TE

P 2

3

Inst

all t

he

rem

ain

ing

co

ntr

ol p

ots

Mou

nt t

he c

ontr

ol p

ots

wit

h th

eir

lugs

fa

cing

up

for s

old

erin

g . W

hen

we

refe

r to

lugs

as

left

or

right

, it’s

ass

umin

g yo

u’re

lo

okin

g at

the

pot

fro

m t

he s

ame

poi

nt

of v

iew

as

in th

e w

iring

dia

gram

.

Mou

nt th

em a

s fo

llow

s:

Inte

nsit

y:

250K

L p

ot

Spee

d:

3MRA

pot

Re

verb

: 10

0KL

pot

Ba

ss:

250K

A p

ot

Treb

le:

250K

A p

ot

Volu

me:

1M

A p

ot

S

TE

P 2

4

Inst

all 1

00

K r

esis

tor

+ 6

.8K

res

isto

rRu

n o

ne

lead

of

the

100K

res

isto

r u

p

thro

ugh

the

bot

tom

of t

he le

ft lu

g of

the

spee

d p

ot a

nd w

rap

it d

own

thro

ugh

the

mid

dle

lug

of

the

sam

e p

ot . I

t d

oes

n’t

mat

ter w

hich

dire

ctio

n th

is re

sist

or is

in-

stal

led,

bec

ause

resi

stor

s are

n’t p

olar

ized

. So

lder

the

resi

stor

lead

to b

oth

lugs

.

Sold

er t

he o

ther

lead

of

this

res

isto

r to

th

e b

ack

of th

e sp

eed

pot

.

Wra

p on

e le

ad o

f the

6 .8

K re

sist

or th

roug

h th

e le

ft lu

g of

the

bas

s p

ot b

ut d

on’t

sol-

der

this

con

nect

ion

yet .

Sold

er th

e 6 .

8K re

sist

or’s

othe

r lea

d to

the

bac

k of

the

bas

s p

ot .

S

TE

P 2

5

Inst

all t

wo

jum

per

sCu

t tw

o w

hite

wire

s, 2

" lon

g . C

onne

ctin

g w

ires

like

this

are

cal

led

jum

per

s .

Wra

p o

ne e

nd o

f a ju

mp

er o

nto

the

mid

-dl

e lu

g of

the

bas

s pot

and

wra

p th

e ot

her

end

of th

is ju

mp

er o

nto

the

left

lug

of th

e tr

eble

pot

. Sol

der

the

con

nect

ion

to t

he

left

lug

of t

he t

reb

le p

ot, b

ut le

ave

the

mid

dle

lug

of t

he b

ass

pot

uns

old

ered

fo

r now

.

Wra

p o

ne e

nd o

f the

oth

er ju

mp

er o

nto

the

mid

dle

lug

of t

he t

reb

le p

ot . W

rap

th

e ot

her

end

onto

the

rig

ht lu

g of

the

vo

lum

e p

ot . S

old

er t

he c

onne

ctio

ns a

t b

oth

ends

of t

his

jum

per

.

S

TE

P 2

6

Inst

all t

wo

jack

s +

a 1

M r

esis

tor

Ad

d in

stru

men

t ja

cks

1 an

d 2

. Pos

itio

n th

em so

the

cent

er lu

g of

jack

2 is

clo

se to

th

e si

de

lug

of ja

ck 1

as

pic

ture

d .

Wra

p o

ne le

ad o

f a

1M r

esis

tor

thro

ugh

the

right

lug

of ja

ck 1

and

wra

p it

ont

o th

e ce

nter

lu

g o

f th

e sa

me

jack

. Mak

e su

re t

his

lead

won

’t b

e in

the

way

whe

n an

inst

rum

ent c

able

is p

lugg

ed in

.

Run

this

resi

stor

’s o

ther

lead

thro

ugh

the

left

lug

of ja

ck 1

and

ont

o th

e ce

nter

lug

of

jack

2 . D

on’t

sold

er th

ese

conn

ectio

ns y

et .

S

TE

P 2

7

Inst

all t

wo

68

K r

esis

tors

Twis

t th

e le

ads

of t

he t

wo

68K

resi

stor

s to

geth

er, c

reat

ing

one

conn

ectio

n . W

rap

th

e ot

her l

ead

from

one

resi

stor

ont

o th

e rig

ht lu

g of

jack

2 a

s sh

own .

Wra

p th

e re

mai

ning

resi

tor l

ead

onto

the

left

lug

of ja

ck 1

, ad

ding

it to

the

conn

ec-

tion

mad

e in

the

pre

viou

s st

ep .

Sold

er a

ll th

ese

con

nec

tio

ns, a

nd

als

o so

lder

the

twis

ted

68K

resi

stor

lead

s .

S

TE

P 2

8

Po

wer

tra

nsf

orm

er b

lack

lead

sRu

n ei

ther

of

the

bla

ck w

ires

fro

m t

he

pow

er tr

ansf

orm

er to

the

sid

e lu

g of

the

fuse

sock

et . T

rim it

to fi

t and

sold

er it

. Trim

an

d so

lder

the

othe

r bla

ck w

ire to

the

left

lu

g on

the

pow

er s

witc

h .

S

TE

P 2

9

Po

wer

tra

nsf

orm

er g

reen

lead

sRu

n th

e tw

o gr

een

wire

s fr

om th

e p

ower

tr

ansf

orm

er to

the

lugs

on

the

pilo

t lam

p

sock

et (e

ither

wire

can

go

to e

ither

lug)

. Tr

im t

hes

e w

ires

to

len

gth

an

d w

rap

th

em o

nto

the

lugs

. Don

’t so

lder

the

se

conn

ectio

ns y

et .

Despite

being

green

, these

aren’

t gro

und wi

res. Th

ey pow

er the

pilot

lamp a

nd tub

e heat

er fila

ments

.

stew

mac

.co

m

16

©20

18 S

tew

Mac

VIB

RAT

OPE

DA

LRE

VER

BPE

DA

LRE

VER

BO

UTP

UT

REV

ERB

INPU

TSP

EAK

ERPO

WER

GRO

UN

DFU

SEEX

TEN

SIO

N

PILO

TLA

MP

V7

5AR4

V6

6V6

V5

6V6

V4

12A

X7

V3

12A

X7

V2

12AT

7V

112

AX

7

INTE

NSI

TYSP

EED

REV

ERB

BA

SSTR

EBLE

VO

LUM

EIN

STRU

MEN

TS

21

4 3

21

87

65

4 3

21

87

65

4 3

21

87

65

6

4321

98 7 5

6

4321

98 7 5

6

4321

98 7 5

6

4321

98 7 5

OU

X

Y

O

–

U

X

Y

4 3

21

87

65

4 3

21

87

65

4 3

21

87

65

6

4321

98 7 5

6

4321

98 7 5

Enla

rged

tosh

ow d

etai

l

stew

mac

.co

m

17

©20

18 S

tew

Mac

S

TE

P 3

0

Po

wer

tra

nsf

orm

er r

ed/y

ello

w le

adTr

im th

e p

ower

tran

sfor

mer

’s re

d/y

ello

w

lead

to a

n ap

pro

pria

te le

ngth

and

sol

der

it

to th

e fr

ont g

roun

ding

str

ip a

s sh

own .

S

TE

P 3

1

Po

wer

tra

nsf

orm

er r

ed le

ads

Trim

the

pow

er tr

ansf

orm

er’s

red

lead

s to

an a

pp

rop

riate

leng

th a

nd w

rap

one

lead

on

to p

in 4

of t

he V

7 tu

be

sock

et (5

AR4

) . So

cket

pin

s hav

e up

per

and

low

er e

yele

ts

for m

ultip

le c

onne

ctio

ns .

Wra

p t

he

oth

er r

ed l

ead

ont

o p

in 6

of

the

sam

e so

cket

. Don

’t so

lder

the

se r

ed

lead

s ye

t .

S

TE

P 3

2

Po

wer

tra

nsf

orm

er y

ello

w le

ads

Trim

the

pow

er tr

ansf

orm

er’s

yello

w le

ads

to a

n ap

pro

pri

ate

leng

th . W

rap

one

of

thes

e le

ads

onto

pin

2 o

f soc

ket V

7 .

Wra

p t

he o

ther

yel

low

lea

d o

nto

pin

8

of t

he s

ame

sock

et . D

on’t

sold

er t

hese

ye

llow

lead

s ye

t .

S

TE

P 3

3

Ou

tpu

t tr

ansf

orm

er

blu

e an

d b

row

n le

ads

Trim

the

blu

e w

ire fr

om th

e ou

tput

tran

s-fo

rmer

to a

n ap

prop

riate

leng

th a

nd w

rap

it

onto

pin

3 o

f soc

ket V

5 . D

on’t

sold

er th

is

conn

ectio

n ye

t .

Trim

th

e b

row

n w

ire

fro

m t

he

ou

tpu

t tr

ansf

orm

er t

o a

n a

pp

rop

riat

e le

ng

th

and

wra

p it

ont

o p

in 3

of s

ocke

t V6 .

Don

’t so

lder

this

con

nect

ion

yet .

Leav

e th

e re

d o

utp

ut t

rans

form

er l

ead

free

for n

ow, y

ou’ll

con

nect

it la

ter,

whe

n th

e ey

elet

boa

rd is

inst

alle

d .

S

TE

P 3

4

Two

jum

per

sA

dd

a 1-

1/2"

whi

te ju

mp

er b

etw

een

the

right

lug

of th

e sp

eake

r jac

k an

d th

e rig

ht

lug

of

the

exte

nsi

on

jac

k . W

rap

th

ese

join

ts, b

ut d

o no

t sol

der

them

yet

.

Cut a

3/4

" whi

te ju

mp

er a

nd re

mov

e th

e in

sula

tion .

Ad

d th

is s

hort

wire

bet

wee

n th

e sp

eake

r jac

k’s l

eft l

ug a

nd c

ente

r lug

. So

lder

the

bot

h en

ds .

S

TE

P 3

5

Ou

tpu

t tr

ansf

orm

er g

reen

an

d

bla

ck le

ads

Trim

thes

e tw

o w

ires t

o re

ach

the

spea

ker

jack

and

ext

ensi

on s

pea

ker j

ack .

Sold

er th

e gr

een

lead

to th

e rig

ht lu

g of

th

e sp

eake

r ja

ck a

long

with

the

jum

per

fr

om th

e p

revi

ous

step

.

Sold

er th

e b

lack

lead

to th

e le

ft lu

g of

the

exte

nsio

n sp

eake

r jac

k .

S

TE

P 3

6

Co

nn

ect

the

reve

rb d

rive

r le

ads

Trim

the

gre

en le

ad to

rea

ch t

he m

iddl

e lu

g o

f th

e re

verb

inp

ut j

ack,

tin

it

and

sold

er it

to th

e lu

g .

Trim

the

bla

ck le

ad t

o re

ach

the

grou

nd

tab

on

the

reve

rb in

put

jack

. Tin

it a

nd

sold

er it

to th

is ta

b .

Trim

the

blu

e le

ad to

reac

h p

in 6

of s

ocke

t V2

. Tin

it a

nd w

rap

it o

nto

the

pin

, but

d

on’t

sold

er it

yet

.

Leav

e th

e re

d l

ead

fre

e fo

r n

ow, y

ou’ll

co

nnec

t it t

o th

e ey

elet

boa

rd la

ter o

n .

S

TE

P 3

7

Ad

d t

hre

e w

hit

e ju

mp

ers

Cut t

wo

3/4"

whi

te ju

mp

ers .

Wra

p o

ne o

f th

em b

etw

een

pin

2 a

nd p

in 7

of s

ocke

t V2

. Sol

der

the

conn

ectio

n to

pin

2 .

Wra

p th

e se

cond

sho

rt ju

mp

er b

etw

een

pin

3 a

nd p

in 8

of s

ocke

t V2

. Sol

der

the

co

nnec

tion

to p

in 3

.

Cut a

2" w

hite

jum

per

and

con

nect

it b

e-tw

een

pin

s 1

and

6 on

soc

ket

V2 . R

oute

th

is j

ump

er i

n a

sem

icir

cle

arou

nd

th

e so

cket

. Sol

der

thi

s ju

mp

er a

t p

in 1

and

al

so a

t p

in 6

whe

re it

join

s th

e b

lue

wire

fr

om th

e re

verb

driv

er .

For ne

at loo

king w

iring, u

se wir

e str

ippers

to tri

m 1/4"

of the

insula

tion

from t

he end

s of th

e push

-back

wire.

stew

mac

.co

m

18

©20

18 S

tew

Mac

VIB

RAT

OPE

DA

LRE

VER

BPE

DA

LRE

VER

BO

UTP

UT

REV

ERB

INPU

TSP

EAK

ERPO

WER

GRO

UN

DFU

SEEX

TEN

SIO

N

PILO

TLA

MP

V7

5AR4

V6

6V6

V5

6V6

V4

12A

X7

V3

12A

X7

V2

12AT

7V

112

AX

7

INTE

NSI

TYSP

EED

REV

ERB

BA

SSTR

EBLE

VO

LUM

EIN

STRU

MEN

TS

21

6

4321

98 7 5

6

4321

98 7 5

6

4321

98 7 5

4 3

21

87

65

4 3

21

87

65

6

4321

98 7 5

6

4321

98 7 5

6

4321

98 7 5

4 3

21

87

65

4 3

21

87

65

O

–

U

X

Y

6

4321

98 7 5

stew

mac

.co

m

19

©20

18 S

tew

Mac

S

TE

P 3

8

Ad

d t

hre

e m

ore

jum

per

sCu

t on

e 3"

gre

en ju

mp

er . W

rap

one

end

on

to p

in 8

of

sock

et V

5 an

d so

lder

thi

s co

nnec

tion .

Trim

aw

ay a

ny e

xces

s w

ire .

Wra

p t

he o

ther

end

of t

his

jum

per

ont

o p

in 8

of s

ocke

t V6 .

Cu

t o

ne

5" g

reen

ju

mp

er .

Sold

er o

ne

end

to

pin

8 o

f so

cket

V6

alo

ng

wit

h th

e ju

mp

er c

omin

g fr

om V

5 . S

old

er t

he

othe

r en

d of

thi

s 8"

jum

per

to

the

fron

t gr

ound

ing

strip

.

Cut o

ne 4

" whi

te ju

mp

er . S

old

er o

ne e

nd

to p

in 4

of s

ocke

t V6,

and

sold

er th

e ot

her

end

the

pin

4 o

f soc

ket V

5 .

S

TE

P 3

9

Two

wh

ite

jum

per

s +

on

e re

sist

or

Cut

one

1-1/

4" w

hite

jum

per

. Sol

der

one

en

d o

nto

the

mid

dle

lug

of

the

reve

rb

outp

ut ja

ck .

Wra

p th

e ot

her e

nd o

nto

the

mid

dle

lug

of th

e re

verb

ped

al ja

ck . D

on’t

sold

er th

is

join

t yet

.

Wra

p a

220

K r

esis

tor

on

to t

he

mid

dle

lug

of

the

reve

rb p

edal

ja

ck . S

old

er t

his

resi

stor

’s o

ther

le

ad t

o t

he

gro

un

d t

ab o

f th

e re

verb

out

put

jack

.

Cut a

1-1

/2" w

hite

jum

per

. Wra

p o

ne e

nd

onto

the

mid

dle

lug

of t

he r

ever

b p

edal

ja

ck a

nd w

rap

the

oth

er e

nd o

nto

pin

2

of s

ocke

t V3

. Sol

der

thi

s ju

mp

er a

t b

oth

ends

.

S

TE

P 4

0

On

e g

reen

jum

per

+ t

hre

e re

sist

ors

Cut

on

e 2"

gre

en j

ump

er . I

nsta

ll it

be-

twee

n fi

lter

cap

’s n

egat

ive

(–)

lug

an

d th

e ne

arb

y gr

ound

ing

stri

p . S

old

er t

he

conn

ectio

ns a

t bot

h en

ds .

Wra

p a

15K

2W re

sist

or b

etw

een

filte

r cap

lu

gs “O

" and

“U

" . D

on’t

sold

er it

yet

.

Twis

t th

e le

ads

of

two

100

Ω r

esis

tors

to

geth

er a

nd a

pp

ly s

old

er to

kee

p th

em

join

ed . W

rap

the

two

resi

stor

s’ o

ther

lead

s on

to t

he p

ilot

lam

p lu

gs a

long

with

the

gr

een

pow

er t

rans

form

er le

ads .

Do

not

sold

er th

ese

yet .

S

TE

P 4

1

Ad

d o

ne

gre

en ju

mp

erCu

t one

4" g

reen

jum

per

. Sol

der

one

end

to

th

e tw

iste

d c

om

bin

ed l

ead

s o

f th

e 10

0Ω re

sist

ors

you

just

con

nect

ed to

the

pilo

t lam

p so

cket

. Sol

der t

he o

ther

end

of

this

jum

per

to th

e fr

ont g

roun

ding

str

ip .

Sto

p a

nd

insp

ect

you

r w

ork

This

is a

goo

d tim

e to

ste

p a

way

from

the

pro

ject

for

a f

ew m

inut

es . T

ake

a b

reak

b

efor

e re

view

ing

your

wor

k fo

r err

ors .

Whe

n yo

u’re

read

y to

go

at it

aga

in, v

ery

care

fully

wal

k th

roug

h ev

ery

conn

ectio

n yo

u’v

e m

ade

so f

ar . W

hen

eve

ryth

ing

chec

ks o

ut, y

ou’re

rea

dy

to m

ove

on t

o th

e ey

elet

boa

rd .

Be sus

piciou

s Ass

ume t

here's

a m

istake

and

you’re

the on

e wh

o’ll find

it!

STOP

Gro

und

tab

stew

mac

.co

m

20

©

2018

Ste

wM

ac

AB

CD

FE

100μ

f

How

to

inst

all p

arts

on

an

eye

let

bo

ard

in t

hre

e st

eps

Wra

p

Don

’t so

lder

the

com

pon

ents

as

th

ey g

o o

nto

th

e ey

elet

b

oar

d .

Inst

ead

wra

p a

ll th

e p

arts

ont

o th

e b

oard

, ben

ding

th

eir l

eads

tigh

tly

so th

e p

arts

st

ay in

pla

ce w

ithou

t sol

der

.

Insp

ect

Whe

n al

l the

par

ts a

re in

pla

ce,

stop

and

insp

ect .

Go

bac

k ov

er

ever

y st

ep .

Car

eful

insp

ectio

n is

the

bes

t w

ay t

o m

ake

sure

yo

ur a

mp

wor

ks t

he fi

rst

time

you

turn

it o

n .

Sold

erSo

lder

eac

h co

nnec

tion

poi

nt

only

on

ce . R

ehea

tin

g t

o ad

d an

othe

r p

art

mak

es a

mes

sy,

fau

lty

sold

er j

oin

t . U

se t

he

sold

erin

g t

ips

on p

age

11 t

o ge

t pro

fess

iona

l res

ults

.

stew

mac

.co

m

21

©

2018

Ste

wM

ac

Wra

pp

ing

par

ts o

nto

th

e b

ias

bo

ard

The

bia

s b

oar

d i

s th

e sm

alle

r o

f th

e tw

o ey

elet

boa

rds .

Pos

ition

it a

s sh

own

abov

e, w

ith

hole

D t

o th

e up

per

rig

ht,

and

the

pai

r of

mou

ntin

g ho

les

tow

ard

the

bot

tom

.

S

TE

P 4

2

Ad

d t

wo

res

isto

rsW

rap

a 1

00K

resi

stor

bet

wee

n ey

elet

s A

an

d B .

Wra

p a

22K

res

isto

r b

etw

een

eyel

ets

E an

d F .

Do

n’t

sold

er t

hes

e co

nn

ecti

ons

. Yo

u’ll

so

lder

the

con

nect

ions

on

bot

h ey

elet

b

oar

ds

late

r, a

fter

all

thei

r p

arts

are

w

rap

ped

in p

lace

and

dou

ble

-che

cked

.

S

TE

P 4

3

Ad

d a

cap

acit

or

and

a d

iod

eW

rap

a 1

00μF

ele

ctro

lytic

cap

bet

wee

n ey

elet

s E a

nd F .

No

te th

e p

ola

rity

of t

he

cap

acit

or.

Con

nect

the

cap

’s n

egat

ive

lead

to

eyel

et F

. Thi

s ca

pac

itor

conn

ects

ne

xt t

o th

e 22

K re

sist

or in

stal

led

in t

he

pre

vio

us s

tep

. As

you

wra

p t

he

lead

s,

allo

w t

he t

wo

par

ts e

noug

h ro

om t

o si

t si

de-

by-s

ide .

Ad

d th

e re

ctifi

er d

iod

e b

etw

een

eyel

ets

B an

d C

. No

te th

e p

ola

rity

. The

pos

itive

le

ad o

f the

dio

de

is in

dica

ted

by a

str

ipe

at t

hat

en

d . T

he

end

wit

h n

o s

trip

e is

ne

gativ

e . C

onne

ct t

he n

egat

ive

lead

to

eyel

et C

.

S

TE

P 4

4

Ad

d t

wo

wh

ite

jum

per

sC

ut a

1"

whi

te j

ump

er . T

urn

the

eyel

et

boa

rd o

ver,

and

add

this

jum

per

bet

wee

n ey

elet

s C

and

F o

n th

e b

ack

of t

he b

ias

boa

rd .

Cut a

3" w

hite

jum

per

. Wra

p o

ne e

nd u

p

thro

ugh

the

bot

tom

of e

yele

t C, a

nd ru

n th

is ju

mp

er u

p th

roug

h ho

le D

. Pul

l it t

ight

to

kee

p it

in p

lace

.

S

TE

P 4

5

Ad

d t

wo

mo

re ju

mp

ers

Cut

a 6"

gre

en ju

mp

er a

nd w

rap

it o

nto

eyel

et E

from

the

fron

t .

Cut

a 7"

whi

te ju

mp

er a

nd w

rap

it o

nto

eyel

et A

from

the

fron

t .

Set

the

bia

s b

oar

d a

sid

e St

ore

the

bia

s b

oard

som

ewhe

re t

hat

it w

on’t

be

dist

urb

ed . Y

ou’re

read

y to

turn

yo

ur a

tten

tion

to th

e m

ain

eyel

et b

oard

.

stew

mac

.co

m

22

©

2018

Ste

wM

ac

15

34

2

10

59

2017

67

89

11

5857

5655

5460

6162

6364

6568

6970

71 72 73 7466

67

1213

1415

1618

1921

2425

2627

3029

2831

2223

3233

3435

3740

4142

4344

4546

4748

4950

5152

5338

3936

+25μF

250

104J 600V

473J 600V

223J 600V510K

+25μF

+25μF

stew

mac

.co

m

23

©

2018

Ste

wM

ac

Wra

pp

ing

par

ts o

nto

th

e m

ain

bo

ard

S

TE

P 4

6

Inst

all a

25

μF

cap

+ a

1.5

K r

esis

tor

Wra

p t

he le

ads

of a

1 .5

K re

sist

or a

roun

d th

e le

ads

of a

25μ

F Sp

ragu

e el

ectr

olyt

ic

cap

acito

r and

sol

der

them

toge

ther

.

Not

e th

e p

olar

ity

of th

e ca

pac

itor .

Inst

all

this

resi

stor

/cap

acito

r ass

emb

ly b

etw

een

eyel

ets

21 a

nd 7

0, m

akin

g su

re t

he c

a-p

acito

r’s n

egat

ive

lead

goe

s to

eye

let 2

1 .

S

TE

P 4

7

Ad

d t

wo

jum

per

s, g

reen

+ w

hit

eCu

t a 4

" gre

en ju

mp

er a

nd w

rap

one

end

on

to e

yele

t 21 .

Cut a

3-1

/2" w

hite

jum

per

and

wra

p o

ne

end

onto

eye

let 7

0 .

S

TE

P 4

8

Ad

d t

wo

wh

ite

jum

per

sC

ut t

wo

12"

whi

te j

ump

ers .

On

one

of

thes

e, m

ark

the

insu

latio

n at

bot

h en

ds

with

a re

d m

arke

r .

Run

bot

h of

thes

e ju

mp

ers d

own

thro

ugh

hole

20,

acr

oss t

he b

ack

of th

e b

oard

, and

up

thro

ugh

hole

53 .

S

TE

P 4

9

Ad

d a

0.1

μF

cap

acit

or

+ o

ne

jum

per

Wra

p a

0 .1

μF

Ora

ng

e D

rop

cap

acit

or

bet

wee

n ey

elet

s 19

and

69 .

Thi

s ca

pac

-ito

r d

oes

not

have

pol

arit

y an

d c

an b

e in

stal

led

in e

ither

dire

ctio

n .

Cu

t an

8-1

/2"

wh

ite

jum

per

. Tu

rn t

he

boa

rd o

ver a

nd w

rap

this

jum

per

thro

ugh

the

bot

tom

of

eyel

et 1

9 . R

un t

he o

ther

en

d of

the

jum

per

up

thro

ugh

hole

17

and

pul

l it t

ight

so

it st

ays

in p

lace

.

S

TE

P 5

0

0.0

47μ

F ca

pac

ito

r +

on

e ju

mp

erA

dd

a 0

.047

μF

Ora

ng

e D

rop

cap

acit

or

bet

wee

n ey

elet

s 18

and

69 .

Thi

s ca

p is

no

t pol

ariz

ed a

nd c

an b

e in

stal

led

faci

ng

eith

er d

irect

ion .

Cu

t an

8-1

/2"

wh

ite

jum

per

an

d m

ark

one

of th

e en

d w

ith b

lue

mar

ker .

Flip

the

boa

rd a

nd w

rap

the

unm

arke

d en

d of

this

ju

mp

er o

nto

the

bac

k of

eye

let

18 . R

un

this

jum

per

up

thro

ugh

hole

17

and

pul

l tig

ht to

kee

p in

pla

ce .

S

TE

P 5

1

100

K r

esis

tor

+ 2

50p

F ca

pac

ito

rW

rap

a 1

00K

resi

sto

r b

etw

een

eye

lets

68

and

69 .

Ad

d a

250

pF

silv

er m

ica

cap

acit

or b

e-tw

een

eyel

ets

68 a

nd 4

2 . T

his

cap

acito

r al

so h

as n

o p

olar

ity

and

can

be

inst

alle

d fa

cing

eith

er w

ay .

S

TE

P 5

2

Inst

all t

wo

wh

ite

jum

per

sA

dd

a 3"

whi

te ju

mp

er to

eye

let 6

8 .

Cut a

5-1

/2"

whi

te ju

mp

er a

nd m

ark

one

end

with

a b

lack

mar

ker .

Turn

the

boa

rd

over

and

wra

p it

s unm

arke

d en

d th

roug

h th

e ba

ck o

f eye

let 4

2 . R

un th

e ot

her e

nd o

f th

is ju

mp

er u

p th

roug

h ho

le 1

7 an

d p

ull

it tig

ht to

kee

p it

in p

lace

.

S

TE

P 5

3

Inst

all t

wo

10

0K

res

isto

rsA

dd

one

100K

res

isto

r b

etw

een

eyel

ets

41 a

nd

68 .

Ad

d a

no

ther

100

K re

sist

or

bet

wee

n ey

elet

s 41

and

67 .

S

TE

P 5

4

Ad

d t

wo

cap

acit

ors

+ a

1M

res

isto

rA

dd

a 0

.022

μF

Ora

ng

e D

rop

cap

acit

or

bet

wee

n ey

elet

s 67

and

40 .

Thi

s ca

p is

no

t pol

ariz

ed .

Ad

d a

500

pF

Silv

er M

ica

cap

acit

or b

e-tw

een

eyel

ets

40 a

nd 3

0 .

Ad

d a

1M

res

isto

r b

etw

een

eye

lets

16

and

30 .

S

TE

P 5

5

Ad

d t

wo

wh

ite

jum

per

sA

dd

a 3"

whi

te ju

mp

er to

eye

let 6

7 .

Cut

one

4" w

hite

jum

per

. Flip

the

boa

rd

over

an

d w

rap

on

e en

d o

f th

e ju

mp

er

thro

ugh

the

bac

k of

eye

let

30 . R

un t

his

jum

per

up

thr

ough

hol

e 52

and

pul

l it

tig

ht .

S

TE

P 5

6

Ad

d t

wo

mo

re c

ap+

resi

sto

r p

airi

ng

sW

rap

the

lead

s of

a 2

.2K

resi

stor

and

a

1 .5K

res

isto

r ar

ou

nd

th

e le

ads

of

two

25μF

Sp

ragu

e el

ectr

olyt

ic c

apac

itors

and

so

lder

them

toge

ther

.

Inst

all

the

2 .2K

res

isto

r/ca

p a

ssem

bly

b

etw

een

eyel

ets

16 a

nd 6

5, a

nd th

e 1 .

5K

resi

stor

/cap

ass

emb

ly b

etw

een

eyel

ets

16 a

nd 6

6 . N

ote

the

pol

arit

y of

the

cap

s,

mak

ing

su

re t

he

neg

ativ

e le

ads

go

to

eyel

et 1

6 .

S

TE

P 5

7

Ad

d t

wo

wh

ite

jum

per

sA

dd

a 3"

whi

te ju

mp

er to

eye

let 6

6 .

Ad

d a

1-1/

2" w

hite

jum

per

to e

yele

t 65 .

70

21

+

25μ

F

Posi

tive

Neg

ativ

e

66

16

65

Posi

tive

+

25μ

F

+

25μ

F

stew

mac

.co

m

24

©20

18 S

tew

Mac

15

34

2

10

59

2017

67

89

11

5857

5655

5460

6162

6364

6568

6970

71 72 73 7466

67

1213

1415

1618

1921

2425

2627

3029

2831

2223

3233

3435

3740

4142

4344

4546

4748

4950

5152

5338

3936

332J 600V

10pF

223J 600V

+25μF

+25μF

+25μF

stew

mac

.co

m

25

©

2018

Ste

wM

ac

S

TE

P 5

8

Ad

d a

gre

en b

ack-

of-

bo

ard

jum

per

Cu

t a

4" g

reen

jum

per

. Flip

th

e ey

elet

b

oard

ove

r and

add

this

jum

per

bet

wee

n ey

elet

16

and

eye

let

21 o

n th

e b

ack

of

the

boa

rd .

S

TE

P 5

9

Ad

d a

3.3

M r

esis

tor

+ a

10

pF

cap

A

dd

a 3 .

3M r

esis

tor

and

a 10

pF

cera

mic

di

sk c

apac

itor b

etw

een

eyel

ets 2

7 an

d 15

. Th

is c

ap is

not

pol

ariz

ed .

S

TE

P 6

0

Ad

d a

470

K r

esis

tor

Ad

d a

470K

res

isto

r b

etw

een

eyel

ets

27

and

14 .

S

TE

P 6

1

Ad

d a

bac

k-o

f-b

oar

d ju

mp

erFl

ip th

e b

oard

ove

r and

add

a 2

-1/4

" whi

te

jum

per

on

the

back

of t

he b

oard

bet

wee

n ey

elet

s 15

and

40 .

S

TE

P 6

2

Ad

d a

.003

3μ

F ca

pac

ito

rA

dd

a .0

033μ

F O

ran

ge

Dro

p c

apac

itor

b

etw

een

eyel

ets

39 a

nd 2

9 . T

his

cap

is

not p

olar

ized

.

S

TE

P 6

3

Ad

d t

hre

e w

hit

e ju

mp

ers

Cut

two

6-1/

2" w

hite

jum

per

s . M

ark

the

end

of o

ne w

ith a

n or

ange

mar

ker .

Flip

th

e b

oar

d o

ver

and

wra

p t

he

un

-m

arke

d en

d of

thi

s ju

mp

er t

hrou

gh t

he

bac

k of

eye

let 2

9 .

Wra

p t

he

seco

nd

ju

mp

er t

hro

ug

h t

he

bac

k of

eye

let 1

4 .

Run

bot

h th

ese

jum

per

s up

thro

ugh

hole

13

and

pul

l the

m t

ight

to

keep

the

m in

p

lace

.

Flip

the

boa

rd o

ver a

nd a

dd a

1-1

/4" w

hite

ju

mp

er o

n th

e ba

ck o

f the

boa

rd b

etw

een

eyel

ets

39 a

nd 6

4 .

S

TE

P 6

4

Ad

d t

wo

10

0K

res

isto

rs +

on

e ca

pA

dd

a 10

0K r

esis

tor

bet

wee

n ey

elet

s 38

an

d 6

4 . A

dd

an

oth

er 1

00K

resi

stor

be-

twee

n ey

elet

s 38

and

62 .

Ad

d a

0 .02

μF O

rang

e D

rop

cap

bet

wee

n ey

elet

s 37

and

62 .

Thi

s ca

pac

itor

is n

ot

pol

ariz

ed .

S

TE

P 6

5

Ad

d t

wo

wh

ite

jum

per

sA

dd

one

3" ju

mp

er to

eye

let 6

4 .

Ad

d on

e 4-

1/2"

jum

per

to e

yele

t 62 .

S

TE

P 6

6

Ad

d a

cap

+ r

esis

tor

pai

rin

gW

rap

the

lead

s of

a 1

.5K

resi

stor

aro

und

the

lead

s of

a 2

5μF

Spra

gue

elec

trol

ytic

ca

pac

itor a

nd s

old

er th

em to

geth

er .

Not

e th

e p

olar

ity

of th

e ca

pac

itor .

Inst

all

this

resi

stor

/cap

acito

r ass

emb

ly b

etw

een

eyel

ets

12 a

nd 6

1, m

akin

g s

ure

the

ca-

pac

itor’s

neg

ativ

e le

ad g

oes

to e

yele

t 12 .

S

TE

P 6

7

Ad

d t

wo

res

isto

rsA

dd

a 2

.7k

resi

stor

bet

wee

n ey

elet

s 12

an

d 26

.

Ad

d a

47o

hm r

esis

tor

bet

wee

n ey

elet

s 11

and

12 .

S

TE

P 6

8

Thre

e ju

mp

ers

Ad

d a

2" w

hite

jum

per

to e

yele

t 61 .

Cut

one

7" w

hite

jum

per

. Flip

the

boa

rd

over

an

d w

rap

on

e en

d o

f th

e ju

mp

er

thro

ugh

the

bot

tom

of e

yele

t 26 .

Run

the

othe

r end

of t

he ju

mp

er u

p th

roug

h ho

le

48 a

nd p

ull t

ight

to k

eep

in p

lace

.

Cut

one

5" w

hite

jum

per

. Flip

the

boa

rd

over

an

d w

rap

on

e en

d o

f th

e ju

mp

er

thro

ugh

the

bot

tom

of e

yele

t 27 .

Run

the

othe

r end

of t

he ju

mp

er u

p th

roug

h ho

le

49 a

nd p

ull t

ight

to k

eep

in p

lace

.

S

TE

P 6

9

Ad

d t

wo

mo

re c

ap+

resi

sto

r p

airi

ng

sW

rap

the

lead

s of

a 3

.3K

resi

stor

and

a

1 .5K

res

isto

r ar

ou

nd

th

e le

ads

of

two

25μF

Sp

ragu

e el

ectr

olyt

ic c

apac

itors

and

sold

er th

em to

geth

er .

Inst

all

the

3 .3K

res

isto

r/ca

p a

ssem

bly

b

etw

een

eyel

ets

11 a

nd 5

9, a

nd th

e 1 .

5K

resi

stor

/cap

ass

emb

ly b

etw

een

eyel

ets

11 a

nd 6

0 . N

ote

the

pol

arit

y of

the

cap

s,

mak

ing

su

re t

he

neg

ativ

e le

ads

go

to

eyel

et 1

1 .

61

12

+

25μ

F

Posi

tive

Neg

ativ

e

60

11

59

Posi

tive

+

25μ

F

+

25μ

F

stew

mac

.co

m

26

©

2018

Ste

wM

ac

15

34

2

10

59

2017

67

89

11

5857

5655

5460

6162

6364

6568

6970

71 72 73 7466

67

1213

1415

1618

1921

2425

2627

3029

2831

2223

3233

3435

3740

4142

4344

4546

4748

4950

5152

5338

3936

.01μF .01μF .02μF

104J 600V

223J 600V

104J 600V

104J 600V

stew

mac

.co

m

27

©20

18 S

tew

Mac

S

TE

P 7

0

Ad

d t

hre

e ju

mp

ers,

wh

ite

and

gre

enCu

t tw

o 4-

1/2"

whi

te ju

mp

ers .

Ad

d on

e to

eye

let 6

0 an

d th

e ot

her t

o ey

elet

59 .

Cut

one

3" g

reen

jum

per

. Flip

the

boa

rd

over

and

ad

d th

is ju

mp

er b

etw

een

eye-

lets

11

and

6 on

the

bac

k of

the

boa

rd .

S

TE

P 7

1

Ad

d t

wo

1M

res

isto

rsA

dd

a 1

M r

esis

tor

bet

wee

n e

yele

ts 9

an

d 11

.

Add

ano

ther

1M

resi

stor

bet

wee

n ey

elet

s 25

and

59 .

S

TE

P 7

2

Ad

d t

hre

e ce

ram

ic d

isk

cap

acit

ors

The

thre

e ca

pac

itors

inst

alle

d in

this

step

ar

e no

t pol

ariz

ed, s

o yo

u ca

n in

stal

l the

m

in e

ither

dire

ctio

n .

Ad

d a

0 .02

μF c

eram

ic d

isk

cap

bet

wee

n ey

elet

s 58

and

36 .

Ad

d a

0 .01

μF c

eram

ic d

isk

cap

bet

wee

n ey

elet

s 36

and

25 .

Ad

d a

0 .01

μF c

eram

ic d

isk

cap

bet

wee

n ey

elet

s 25

and

9 .

S

TE

P 7

3

Ad

d t

wo

wh

ite

jum

per

sCu

t on

e 8"

whi

te j

ump

er a

nd a

dd

it t

o ey

elet

9 . R

un th

is ju

mp

er d

own

thro

ugh

ho

le 1

0, a

cros

s th

e b

ack

of

the

eyel

et

boa

rd a

nd b

ack

up th

roug

h ho

le 4

7 . P

ull

it tig

ht to

kee

p it

in p

lace

.

Cut

one

7" w

hite

jum

per

. Mar

k on

e en

d w

ith a

blu

e m

arke

r . W

rap

the

unm

arke

d en

d on

to e

yele

t 25 .

Run

the

mar

ked

end

dow

n th

roug

h ho

le 1

0, a

cros

s th

e b

ack

of

the

bo

ard

an

d u

p t

hro

ug

h h

ole

47 .

Pu

ll it

tight

.

S

TE

P 7

4

Ad

d t

hre

e w

hit

e ju

mp

ers

Ad

d a

2" w

hite

jum

per

to e

yele

t 58 .

Cut

one

7" w

hite

jum

per

. Mar

k on

e en

d w

ith a

blu

e m

arke

r . Fl

ip t

he b

oard

ove

r an

d w

rap

the

unm

arke

d en

d th

roug

h th

e b

ack

of e

yele

t 36 .

Run

the

mar

ked

end

up

thro

ugh

hole

7 a

nd p

ull i

t tig

ht .

Flip

th

e b

oar

d a

gai

n a

nd

ad

d a

1-1

/4"

jum

per

bet

wee

n ey

elet

s 57

an

d 5

8 on

th

e b

ack

of th

e b

oard

.

S

TE

P 7

5

Ad

d a

res

isto

r, a

cap

+ a

jum

per

Ad

d a

1M

res

isto

r b

etw

een

eye

lets

57

and

35 .

Ad

d a

0 .1μ

F O

rang

e D

rop

cap

bet

wee

n ey

elet

s 35

and

8 . T

his c

ap is

not

pol

ariz

ed .

Cut a

6" w

hite

jum

per

. Flip

the

boa

rd o

ver

and

wra

p o

ne e

nd t

hrou

gh t

he b

ack

of

eyel

et 8

. Run

this

jum

per

up

thro

ugh

hole

7

and

pul

l it t

ight

.

S

TE

P 7

6

Ad

d o

ne

cap

acit

or

+ o

ne

resi

sto

rA

dd

a 0

.02μ

F O

ran

ge

Dro

p c

apac

ito

r b

etw

een

eyel

ets

6 an

d 35

. Thi

s ca

p is

not

p

olar

ized

.

Ad

d a

220K

res

isto

r b

etw

een

eyel

ets

34

and

57 .

S

TE

P 7

7

Ad

d t

hre

e re

sist

ors

Ad

d a

1M

res

isto

r b

etw

een

eye

lets

33

and

56 .

Ad

d a

1K

resi

sto

r b

etw

een

eye

lets

33

and

55 .

Ad

d a

56k

res

isto

r b

etw

een

eyel

ets

33

and

6 .

S

TE

P 7

8

Ad

d t

hre

e ju

mp

ers

Ad

d a

1-1/

2" w

hite

jum

per

to e

yele

t 56 .

Ad

d a

2" w

hite

jum

per

to e

yele

t 55 .

Ad

d a

6" g

reen

jum

per

to e

yele

t 6 .

S

TE

P 7

9

Two

res

isto

rs +

on

e ca

pac

ito

rA

dd

one

220K

res

isto

r b

etw

een

eyel

ets

5 an

d 24

. Ad

d an

othe

r 22

0K r

esis

tor

be-

twee

n ey

elet

s 3

and

24 .

Ad

d a

0 .1μ

F O

rang

e D

rop

cap

acito

r b

e-tw

een

eyel

ets

5 an

d 55

. Thi

s ca

p is

not

p

olar

ized

.

S

TE

P 8

0

Ad

d o

ne

resi

sto

r +

on

e ca

pac

ito

rA

dd

a 5

6k r

esis

tor

bet

wee

n ey

elet

s 44

an

d 32

.

Ad

d a

0 .1μ

F O

rang

e D

rop

cap

bet

wee

n ey

elet

s 3

and

44 . T

his

cap

isn’

t pol

ariz

ed .

stew

mac

.co

m

28

©

2018

Ste

wM

ac

15

34

2

10

59

2017

67

89

11

5857

5655

5460

6162

6364

6568

6970

71 72 73 7466

67

1213

1415

1618

1921

2425

2627

3029

2831

2223

3233

3435

3740

4142

4344

4546

4748

4950

5152

5338

3936

stew

mac

.co

m

29

©20

18 S

tew

Mac

S

TE

P 8

3

Ad

d s

ix w

hit

e ju

mp

ers

Ad

d a

1" w

hite

jum

per

on

the

bac

k of

the

boa

rd b

etw

een

eyel

ets

2 an

d 22

.

Ad

d a

6" w

hite

jum

per

to e

yele

t 54 .

Cut a

2" w

hite

jum

per

. Flip

the

boa

rd o

ver

and

wra

p o

ne e

nd t

hrou

gh t

he b

ack

of

eyel

et 1

. Run

this

jum

per

up

thro

ugh

hole

71

and

pul

l it t

ight

.

Cut a

1-3

/4" w

hite

jum

per

. Flip

the

boa

rd

and

wra

p it

to th

e b

ack

of e

yele

t 22 .

Run

it

up th

roug

h ho

le 7

2 an

d p

ull i

t tig

ht .

Cut a

5" w

hite

jum

per

. Flip

the

boa

rd a

nd

wra

p it

to th

e b

ack

of e

yele

t 22 .

Run

the

this

jum

per

up

thro

ugh

hole

73

and

pul

l it

tight

.

Cut a

2" w

hite

jum

per

. Flip

the

boa

rd a

nd

wra

p it

to th

e b

ack

of e

yele

t 54 .

Run

it u

p

thro

ugh

hole

74

and

pul

l it t

ight

.

S

TE

P 8

4

Ad

d t

wo

flyi

ng

jum

per

sFl

ying

jum

per

s ar

e w

ires

that

trav

el o

ver

the

boa

rd, j

ump

ing

from

one

eye

let

to

anot

her .

Thes

e ar

e ve

ry c

omm

on in

cla

ssic

p

oint

-to

-poi

nt c

ircui

ts .

Cut a

4" w

hite

jum

per

. Flip

the

boa

rd o

ver

and

wra

p o

ne e

nd t

hrou

gh t

he b

ack

of

eyel

et 4

1 . R

un t

his

jum

per

up

thr

oug

h ho

le 3

1, p

ull i

t tig

ht, a

nd ru

n it

bac

k do

wn

thro

ugh

hole

51 .

Wra

p t

his

end

thro

ugh

the

bac

k of

eye

let 3

8 .

Cut a

7" w

hite

jum

per

. Flip

the

boa

rd a

nd

wra

p it

to th

e b

ack

of e

yele

t 63 .

Run

this

ju

mp

er u

p t

hrou

gh h

ole

51, p

ull i

t tig

ht,

and

leav

e th

e en

d of

thi

s fly

ing

for

now

. Yo

u’ll

be

twis

ting

this

lead

toge

ther

with

ot

her fl

ying

lead

s .

S

TE

P 8

5

Ad

d t

wo

mo

re fl

yin

g ju

mp

ers

Cut

a 1

2" w

hite

jum

per

. Flip

the

boa

rd

and

wra

p t

his

jum

per

thr

ough

the

bac

k of

eye

let 3

8 . R

un th

e fr

ee e

nd u

p th

roug

h ho

le 5

1 an

d p

ull i

t tig

ht . L

eave

thi

s en

d fly

ing

for n

ow .

Cut a

6-1

/2" w

hite

jum

per

. Flip

the

boa

rd

and

wra

p o

ne e

nd t

hrou

gh t

he b

ack

of

eyel

et 3

7 . R

un t

his

jum

per

up

thr

oug

h ho

le 5

0 an

d p

ull i

t tig

ht .

S

TE

P 8

6

Twis

t th

e fl

yin

g ju

mp

ers

Car

eful

ly tw

ist t

hese

thre

e fly

ing

jum

per

s to

geth

er, b

endi

ng t

hem

tow

ard

the

left

si

de o

f the

boa

rd . Y

ou w

ant t

hese

jum

per

s to

be

up a

nd

aw

ay f

rom

com

pon

ents

. Be

car

eful

not

to

dist

urb

the

ir w

rap

ped

co

nnec

tions

to th

e ey

elet

s .

Rev

iew

th

is p

age

bef

ore

sta

rtin

gTh

e di

agra

m sh

ows a

lot o

f jum

per

s now

, so

it’s

a g

ood

idea

to re

ad th

e st

eps

and

unde

rsta

nd w

here

eac

h w

ire g

oes b

efor

e di

ving

in .

S

TE

P 8

1

Ad

d fo

ur

wh

ite

jum

per

sA

dd

a 3"

jum

per

to e

yele

t 44 .

Cut a

6" w

hite

jum

per

. Flip

the

boa

rd o

ver

and

wra

p o

ne e

nd t

hrou

gh t

he b

ack

of

eyel

et 2

4 . R

un t

his

jum

per

up

thr

ough

ho

le 4

and

pul

l it t

ight

.

Cut a

4-1

/2" w

hite

jum

per

. Flip

the

boa

rd

and

wra

p it

thro

ugh

the

bac

k of

eye

let 5

. Ru

n th

is ju

mp

er u

p th

roug

h ho

le 4

3 an

d p

ull i

t tig

ht to

kee

p it

in p

lace

.

Cut a

6" w

hite

jum

per

. Flip

the

boa

rd a

nd

wra

p th

is o

nto

the

bac

k of

eye

let 3

. Run

it

up th

roug

h ho

le 4

3 an

d p

ull i

t tig

ht .

ST

EP

82

Ad

d t

wo

res

isto

rsA

dd

a 1

K 2W

res

isto

r b

etw

een

eye

lets

54

and

22 .

Ad

d a

15K

2W r

esis

tor

bet

wee

n ey

elet

s 22

and

1 .

stew

mac

.co

m

30

©

2018

Ste

wM

ac

15

34

2

10

59

2017

67

89

11

5857

5655

5460

6162

6364

6568

6970

71 72 73 7466

67

1213

1415

1618

1921

2425

2627

3029

2831

2223

3233

3435

3740

4142

4344

4546

4748

4950

5152

5338

3936

stew

mac

.co

m

31

©

2018

Ste

wM

ac

S

TE

P 8

7

Iden

tify

th

e fl

yin

g ju

mp

ers

Use

a m

ulti

met

er t

o id

enti

fy t

he fl

ying

ju

mp

er t

hat

has

cont

inui

ty t

o ey

elet

63 .

Ru

n th

at ju

mp

er d

own

thro

ugh

hole

46

and

wra

p it

thro

ugh

the

bac

k of

eye

let 3

4 .

Fin

d t

he

flyin

g j

ump

er w

ith

cont

inui

ty

to e

yele

t 37 .

Wra

p th

e en

d of

this

jum

per

d

own

onto

eye

let 5

6 .

S

TE

P 8

8

Ad

d t

wo

wh

ite

jum

per

sCu

t a 6

" whi

te ju

mp

er . F

lip th

e b

oard

ove

r an

d w

rap

one

end

thr

ough

the

bac

k of

ey

elet

34 .

Run

thi

s ju

mp

er u

p t

hrou

gh

hole

46,

pul

l it

tight

, and

tw

ist

it in

with

th

e fly

ing

jum

per

stil

l rem

aini

ng a

bov

e th

e b

oard

.

Cu

t a

6" w

hit

e ju

mp

er .

Flip

th

e b

oar

d an

d w

rap

it t

hrou

gh t

he b

ack

of e

yele

t 32

. Run

thi

s ju

mp

er u

p t

hrou

gh h

ole

45,

pul

l it t

ight

, and

twis

t it i

n w

ith th

e fly

ing

jum

per

s .

S

TE

P 8

9

Inst

alli

ng

flyi

ng

jum

per

sU

se a

mul

timet

er to

find

the

flyin

g ju

mp

er

with

con

tinui

ty to

eye

let 3

2 . W

rap

the

end

of th

is ju

mp

er o

nto

eyel

et 1

.

Find

the

flyin

g ju

mp

er w

ith c

ontin

uity

to

eyel

et 3

4 . W

rap

the

end

of

this

jum

per

d

own

onto

eye

let 2

.

The

one

rem

aini

ng fl

ying

jum

per

will

be

sold

ered

to th

e fil

ter c

apac

itor l

ater

.

Sto

p a

nd

rev

iew

Now

all

the

com

pon

ents

and

wire

s are

on

the

eyel

et b

oard

. Sto

p a

nd t

ake

a b

reak

so

you

’ll h

ave

fres

h ey

es t

o re

view

you

r w

ork

bef

ore

sold

erin

g .

Mak

e su

re y

ou’v

e fo

llow

ed

each

step

cor

rect

ly . I

t wou

ld

be

surp

risi

ng

to

fin

d n

o m

ista

kes

at t

his

poi

nt, a

nd

it’s

muc

h le

ss w

ork

to fi

nd a

nd fi

x th

em

now

rath

er th

an a

fter

sol

der

ing!

As

you

’re

chec

kin

g y

ou

r w

ork

, m

ake

sure

all

your

con

nect

ions

are

tigh

t . D

on’t

coun

t on

sol

der

to

“glu

e” y

our

join

ts—

mak

e th

em m

ech

anic

ally

tig

ht

bef

ore

so

lder

is e

ver a

pp

lied

.

S

TE

P 9

0

Sold

er b

oth

eye

let

bo

ard

sTh

e co

mp

onen

ts a

nd ju

mp

ers a

re o

n th

e b

oard

s an

d d

oub

le-c

heck

ed f

or c

orre

ct

pla

cem

ent

and

tight

wra

ps .

It’s

tim

e se

t th

e co

nnec

tions

with

sol

der

.

Revi

ew “T

ips f

or g

reat

sold

erin

g” o

n p

age

11, t

hen

sold

er e

ach

conn

ectio

n on

the

ey

elet

boa

rd .

Aft

er a

ll th

e jo

ints

are

sol

der

ed, c

lip t

he

exce

ss le

ads

on th

e fr

ont a

nd b

ack

of th

e b

oar

d . T

rim

min

g t

hes

e ex

cess

lea

ds

is

imp

orta

nt to

avo

id a

shor

t in

your

circ

uit .

Che

ck a

ll yo

ur s

old

er j

oint

s to

see

tha

t th

ey’re

shi

ny, a

nd to

mak

e su

re t

hat

you

have

n’t m

isse

d on

e .

SLOW

STOP

stew

mac

.co

m

32

©

2018

Ste

wM

ac

VIB

RAT

OPE

DA

LRE

VER

BPE

DA

LRE

VER

BO

UTP

UT

REV

ERB

INPU

TSP

EAK

ERPO

WER

GRO

UN

DFU

SEEX

TEN

SIO

N

PILO

TLA

MP

V7

5AR4

V6

6V6

V5

6V6

V4

12A

X7

V3

12A

X7

V2

12AT

7V

112

AX

7

INTE

NSI

TYSP

EED

REV

ERB

BA

SSTR

EBLE

VO

LUM

EIN

STRU

MEN

TS

21

4 3

21

87

65

4 3

21

87

65

4 3

21

87

65

6

4321

98 7 5

6

4321

98 7 5

6

4321

98 7 5

6

4321

98 7 5

OU

X

Y

O

–

U

X

Y

4 3

21

87

65

4 3

21

87

65

4 3

21

87

65

6

4321

98 7 5

6

4321

98 7 5

15

34

2

10

59

2017

67

89

11

5857

5655

5460

6162

6364

6568

6970

71 72 73 7466

67

1213

1415

1618

1921

2425

2627

3029

2831

2223

3233

3435

3740

4142

4344

4546

4748

4950

5152

5338

3936

+25μF

250250

104J 600V

473J 600V

223J 600V510K

+25μF

+25μF

332J 600V

10pF

223J 600V

+25μF

+25μF

+25μF

.01μF .01μF .02μF

104J 600V

223J 600V104J 600V

104J 600V

AB

CD

FE

100μ

f 10

0μf

stew

mac

.co

m

33

©

2018

Ste

wM

ac

S

TE

P 9

1

Inst

all t

he

bo

ard

s in

th

e ch

assi

sBe

fore

inst

allin

g th

e m

ain

eyel

et b

oard

an

d in

sula

tor b

oard

in th

e ch

assi

s, m

ake

sure

th

e u

nso

lder

ed j

um

per

s co

min

g th

roug

h ho

les

20 a

nd 5

3 ha

ve e

noug

h le

ngth

to re

ach

thei

r com

pon

ents

. Pla

ce

the

eyel

et b

oard

in t

he c

hass

is w

here

it

will

be

mou

nted

and

adj

ust t

hese

jum

p-

ers

until

they

reac

h th

eir c

omp

onen

ts .

Lay

the

mai

n in

sula

tor b

oard

on

the

bot

-to

m o

f th

e ch

assi

s, a

ligni

ng it

wit

h th

e m

ount

ing

hole

s . A

lign

the

mai

n ey

elet

b

oard

ove

r th

e in

sula

tor

boa

rd . P

ass

a 6-

32 x

1/2

" m

achi

ne s

crew

thr

ough

the

ey

elet

bo

ard

, th

e in

sula

tor

bo

ard

, an

d th

e ch

assi

s . S

ecur

e it

with

a lo

cknu

t on

th

e ou

tsid

e of

the

cha

ssis

. Do

the

sam

e w

ith th

e se

cond

bol

t .

Inst

all t

he b

ias

boa

rd in

the

sam

e w

ay:

insu

lato

r fir

st, e

yele

t b

oard

on

top

and

m

ou

nte

d w

ith

6-3

2 x

1/2

" m

ach

ine

scre

ws .

S

TE

P 9

2

Sold

er t

ub

e so

cket

V7

Wra

p t

he w

hite

jum

per

fro

m e

yele

t 54

on

to p

in 8

on

tub

e so

cket

V7

alon

g w

ith

the

yello

w p

ower

tran

sfor

mer

lead

.

Wra

p t

he w

hite

jum

per

from

bia

s b

oard

ey

elet

A o

nto

pin

4 o

f soc

ket V

7 .

Sold

er a

ll th

e co

nnec

tions

to t

his

sock

et

(six

wire

s) a

nd tr

im th

e ex

cess

wire

end

s .

S

TE

P 9

3

Sold

er t

ub

e so

cket

V6

Test

the

tw

o ju

mp

ers

com

ing

from

hol

e 43

to id

entif

y th

e on

e w

ith c

ontin

uity

to

eyel

et 3

. Sol

der

thi

s ju

mp

er t

o p

in 5

of

sock

et V

6 .

You

sh

ou

ld h

ave

jum

per

s so

lder

ed t

o p

ins

3, 4

, 5 a

nd 8

. Sol

der

any

uns

old

ered

co

nnec

tions

on

this

soc

ket n

ow a

nd tr

im

the

wire

end

s .

S

TE

P 9

4

Sold

er t

ub

e so

cket

V5

Sold

er t

he

oth

er j

ump

er c

om

ing

fro

m

ho

le 4

3 to

pin

5 o

f so

cket

V5 .

Tes

t to

m

ake

sure

thi

s ju

mp

er h

as c

ontin

uity

to

eyel

et 5

.

Sold

er t

he ju

mp

er c

omin

g fr

om h

ole

73

to p

in 4

of s

ocke

t V5 .

Thi

s ju

mp

er s

houl

d ha

ve c

ontin

uity

to e

yele

t 22 .

You

sh

ou

ld h

ave

jum

per

s so

lder

ed t

o p

ins

3, 4

, 5 a

nd 8

. Sol

der

any

uns

old

ered

co

nnec

tions

on

this

soc

ket n

ow a

nd tr

im

the

wire

end

s .

S

TE

P 9

5

Sold

er t

ub

e so

cket

V4

Wra

p th

e ju

mp

er fr

om e

yele

t 44

to p

in 6

of

soc

ket V

4 .

Wra

p th

e ju

mp

er fr

om e

yele

t 58

to p

in 1

of

soc

ket V

4 .

Wra

p th

e ju

mp

er fr

om e

yele

t 56

to p

in 7

of

soc

ket V

4 .

Wra

p th

e ju

mp

er fr

om e

yele

t 55

to p

in 8

of

soc

ket V

4 .

Test

th

e tw

o ju

mp

ers

com

ing

thr

oug

h ho

le 4

7 to

see

whi

ch o

ne h

as c

ontin

uity

to

eye

let 9

. Sol

der

this

jum

per

to p

in 2

of

sock

et V

4 .

Wra

p th

e ju

mp

er fr

om e

yele

t 59

to p

in 3

of

soc

ket V

4 .

Sold

er th

e co

nnec

tions

to th

is s

ocke

t (si

x w

ires)

. Trim

the

wire

end

s .

S

TE

P 9

6

Sold

er t

ub

e so

cket

V3

Wra

p th

e ju

mp

er fr

om e

yele

t 62

to p

in 6

of

sock

et V

3 . R

un th

is le

ad a

long

the

floor

of

the

chas

sis t

o th

e ot

her s

ide

of th

e tu

be

sock

et . T

his l

ead

carr

ies h

igh

volt

age

and

runn

ing

it ag

ains

t the

floo

r hel

ps d

ista

nce

it fr

om o

ther

wire

s—w

hich

cou

ld c

reat

e un

wan

ted

hum

.

Wra

p th

e ju

mp

er fr

om e

yele

t 64

to p

in 1

of

soc

ket V

3 .

Wra

p th

e ju

mp

er c

omin

g th

roug

h ho

le 4

9 to

pin

7 o

f soc

ket V

3 . T

his

jum

per

sho

uld

have

con

tinui

ty to

eye

let 2

7 .

Wra

p th

e ju

mp

er fr

om e

yele

t 60

to p

in 3

of

soc

ket V

3 .

Wra

p th

e ju

mp

er fr

om e

yele

t 61

to p

in 8

of

soc

ket V

3 .

Wra

p th

e ju

mp

er c

omin

g fr

om th

e re

verb

p

edal

jack

to p

in 2

of s

ocke

t V3 .

Sold

er th

e co

nnec

tions

to th

is s

ocke

t (si

x w

ires)

. Trim

the

wire

end

s .

Inst

alli

ng

an

d s

old

erin

g t

he

bo

ard

s

stew

mac

.co

m

34

©

2018

Ste

wM

ac

VIB

RAT

OPE

DA

LRE

VER

BPE

DA

LRE

VER

BO

UTP

UT

REV

ERB

INPU

TSP

EAK

ERPO

WER

GRO

UN

DFU

SEEX

TEN

SIO

N

PILO

TLA

MP

V7

5AR4

V6

6V6

V5

6V6

V4

12A

X7

V3

12A

X7

V2

12AT

7V

112

AX

7

INTE

NSI

TYSP

EED

REV

ERB

BA

SSTR

EBLE

VO

LUM

EIN

STRU

MEN

TS

21

4 3

21

87

65

4 3

21

87

65

4 3

21

87

65

6

4321

98 7 5

6

4321

98 7 5

OU

X

Y

O

–

U

X

Y

6

4321

98 7 5

6

4321

98 7 56

4321

98 7 5

6

4321

98 7 5

15

34

2

10

59

2017

67

89

11

5857

5655

5460

6162

6364

6568

6970

71 72 73 7466

67

1213

1415

1618

1921

2425

2627

3029

2831

2223

3233

3435

3740

4142

4344

4546

4748

4950

5152

5338

3936

AB

CD

FE

+25μF

250250

104J 600V

473J 600V

223J 600V510K

+25μF

+25μF

332J 600V

10pF

223J 600V

+25μF

+25μF

+25μF

.01μF .01μF .02μF

104J 600V

223J 600V

104J 600V

104J 600V

100μ

f 10

0μf

stew

mac

.co

m

35

©

2018

Ste

wM

ac

S

TE

P 9

7

Sold

er t

ub

e so

cket

V2

Wra

p t

he ju

mp

er fr

om h

ole

52 o

nto

pin

7

of s

ocke

t V2

. Thi

s ju

mp

er s

houl

d ha

ve

cont

inui

ty to

eye

let 3

0 .

Wra

p th

e ju

mp

er fr

om e

yele

t 65

onto

pin

8

of s

ocke

t V2 .

Do

ub

le-c

hec

k to

be

sure

th

e ju

mp

er

from

pin

7 t

o p

in 2

is s

ecur

ely

wra

pp

ed

onto

pin

7 .

Als

o m

ake

sure

the

jum

per

from

pin

8 to

p

in 3

is w

rap

ped

in p

lace

on

pin

8 .

Sold

er th

e co

nnec

tions

to th

is s

ocke

t (si

x w

ires)

. Trim

the

wire

end

s .

S

TE

P 9

8

Sold

er t

ub

e so

cket

V1

Wra

p th

e ju

mp

er fr

om e

yele

t 67

onto

pin

6

on s

ocke

t V1 .

Wra

p th

e ju

mp

er fr

om e

yele

t 68

onto

pin

1

of s

ocke

t V1 .

Wra

p t

he

un

mar

ked

ju

mp

er c

om

ing

thro

ugh

hole

53

onto

pin

7 o

f soc

ket V

1 .

Wra

p th

e ju

mp

er fr

om e

yele

t 66

onto

pin

8

of s

ocke

t V1 .

Wra

p t

he r

ed m

arke

d ju

mp

er fr

om h

ole

53 o

nto

pin

2 o

f soc

ket V

1 .

Wra

p th

e ju

mp

er fr

om e

yele

t 70

onto

pin

3

of s

ocke

t V1 .

Sold

er th

e co

nnec

tions

to th

is s

ocke

t (si

x w

ires)

. Trim

the

wire

end

s .

S

TE

P 9

9

Sold

er t

he

inst

rum

ent

inp

ut

jack

sSo

lder

the

red

-mar

ked

jum

per

from

hol

e 20

ont

o th

e tw

iste

d p

air

of 6

8K r

esis

tor

lead

s co

min

g fr

om th

e in

put

jack

s .

Sold

er t

he g

reen

jum

per

from

eye

let

21

onto

the

right

lug

of in

put

jack

1 .

Sold

er a

ny r

emai

nin

g u

nsol

der

ed c

on-

nect

ions

on

the

inp

ut ja

cks

and

trim

the

exce

ss w

ires .

ST

EP

10

0

Sold

er t

he

volu

me

po

tSo

lder

the

unm

arke

d ju

mp

er f

rom

hol

e 20

to th

e m

iddl

e lu

g of

the

volu

me

pot

.

Cut

a 1"

gre

en ju

mp

er a

nd r

emov

e th

e sh

ield

ing .

Sol

der

one

end

of

this

to

the

left

lu

g o

f th

e vo

lum

e p

ot . S

old

er t

he

othe

r end

to th

e b

ack

of th

e vo

lum

e p

ot .

S

TE

P 1

01

Sold

er t

he

treb

le p

ot

Find

the

jum

per

com

ing

thro

ugh

hole

17

that

you

mar

ked

wit

h b

lack

ink .

Sol

der

th

is to

the

right

lug

of th

e tr

eble

pot

.

S

TE

P 1

02

Sold

er t

he

bas

s p

ot

Twis

t th

e tw

o ju

mp

ers

toge

ther

that

are

co

min

g th

roug

h ho

le 1

7 . Id

entif

y w

hich

of

thes

e ju

mp

ers h

as c

ontin

uity

to e

yele

t 19

and

sol

der

it to

the

mid

dle

lug

of t

he

bas

s p

ot a

long

with

the

jum

per

alre

ady

in p

lace

.

Fin

d t

he

blu

e-m

arke

d j

um

per

co

min

g th

roug

h ho

le 1

7 th

at h

as c

onti

nuit

y to

ey

elet

18 .

Sol

der

thi

s ju

mp

er t

o th

e le

ft

lug

of th

e b

ass p

ot a

long

with

the

resi

stor

le

ad a

lread

y in

pla

ce .

S

TE

P 1

03

Sold

er t

he

reve

rb p

ot

Take

the

tw

o ju

mp

ers

com

ing

thro

ugh

hole

13

and

twis

t the

m to

geth

er . I

dent

ify

the

jum

per

that

you

mar

ked

oran

ge, a

nd

sold

er it

to th

e rig

ht lu

g of

the

reve

rb p

ot .

Fin

d t

he

jum

per

com

ing

thr

oug

h h

ole

13 t

hat

has

cont

inui

ty t

o ey

elet

14 .

Sol

-d

er t

his

jum

per

to

the

mid

dle

lug

of t

he

reve

rb p

ot .

Cut

a 1"

gre

en ju

mp

er a

nd r

emov

e th

e sh

ield

ing .

Sol

der

one

end

of

this

to

the

left

lug

of th

e re

verb

pot

. Sol

der t

he o

ther

en

d to

the

bac

k of

the

reve

rb p

ot .

stew

mac

.co

m

36

©

2018

Ste

wM

ac

VIB

RAT

OPE

DA

LRE

VER

BPE

DA

LRE

VER

BO

UTP

UT

REV

ERB

INPU

TSP

EAK

ERPO

WER

GRO

UN

DFU

SEEX

TEN

SIO

N

PILO

TLA

MP

V7

5AR4

V6

6V6

V5

6V6

V4

12A

X7

V3

12A

X7

V2

12AT

7V

112

AX

7

INTE

NSI

TYSP

EED

REV

ERB

BA

SSTR

EBLE

VO

LUM

EIN

STRU

MEN

TS

21

OU

X

Y

4 3

21

87

65

4 3

21

87

65

4 3

21

87

65

6

4321

98 7 5

6

4321

98 7 5

6

4321

98 7 5

6

4321

98 7 5

VIB

RAT

OPE

DA

LRE

VER

BPE

DA

LRE

VER

BO

UTP

UT

REV

ERB

INPU

TSP

EAK

ERPO

WER

GRO

UN

DFU

SEEX

TEN

SIO

N

PILO

TLA

MP

V7

5AR4

V6

6V6

V5

6V6

V4

12A

X7

V3

12A

X7

V2

12AT

7V

112

AX

7

15

34

2

10

59

2017

67

89

11

5857

5655

5460

6162

6364

6568

6970

71 72 73 7466

67

1213

1415

1618

1921

2425

2627

3029

2831

2223

3233

3435

3740

4142

4344

4546

4748

4950

5152

5338

3936

AB

CD

FE

100μ

f

+25μF

250250

104J 600V

473J 600V

223J 600V510K 510K

+25μF

+25μF

332J 600V

10pF

223J 600V

+25μF

+25μF

+25μF

.01μF .01μF .02μF

104J 600V

223J 600V104J 600V

104J 600V

stew

mac

.co

m

37

©

2018

Ste

wM

ac

S

TE

P 1

04

Sold

er t

he

spee

d p

ot

Fin

d t

he

jum

per

com

ing

thr

oug

h h

ole

7 th

at y

ou

mar

ked

wit

h b

lue

ink .

Th

is

sho

uld

hav

e co

nti

nu

ity

to e

yele

t 36

. So

lder

this

jum

per

to th

e rig

ht lu

g of

the

spee

d p

ot .

S

TE

P 1

05

Sold

er t

he

inte

nsi

ty p

ot

Iden

tify

the

jum

per

com

ing

thro

ugh

hole

7

that

has

con

tinui

ty t

o ey

elet

8 . S

old

er

this

to

the

right

lug

of t

he in

tens

ity

pot

af

ter t

wis

ting

it to

geth

er w

ith th

e ju

mp

er

from

hol

e 4 .

The

jum

per

co

min

g t

hro

ug

h h

ole

4

shou

ld h

ave

cont

inui

ty to

eye

let 2

4 . S

ol-

der

thi

s ju

mp

er t

o th

e m

iddl

e lu

g of

the

in

tens

ity

pot

.

Fin

d t

he

jum

per

com

ing

thr

oug

h h

ole

D o

f th

e b

ias

boa

rd t

hat

has

cont

inui

ty

to e

yele

t C o

f the

bia

s b

oard

. Sol

der

this

ju

mp

er to

the

left

lug

of th

e in

tens

ity

pot

.

S

TE

P 1

06

Sold

er t

he

filt

er c

apac

ito

rM

ake

sure

the

rem

aini

ng fl

ying

lead

has

co

ntin

uity

to

eyel

ets

38 a

nd 4

1 . S

old

er

this

lea

d i

n t

o th

e “O

” lu

g o

f th

e fil

ter

cap

alo

ng w

ith t

he r

esis

tor

lead

alre

ady

in p

lace

.

Sold

er th

e le

ad fr

om h

ole

71 to

lug

“U” o

f th

e fil

ter c

ap a

long

with

the

resi

stor

lead

al

read

y in

pla

ce . T

his

lead

sho

uld

hav

e co

ntin

uity

to e

yele

t 1 .

Sold

er t

he le

ad f

rom

hol

e 72

to

lug

“X”

of t

he fi

lter

cap

alo

ng w

ith

the

resi

stor

le

ad a

lread

y in

pla

ce . T

his

shou

ld h

ave

cont

inui

ty to

eye

let 2

2 .

Sold

er th

e le

ad fr

om h

ole

74 to

lug

“Y” o

f th

e fil

ter c

ap a

long

with

the

resi

stor

lead

al

read

y in

pla

ce . T

his

lead

sho

uld

hav

e co

ntin

uity

to e

yele

t 54 .

S

TE

P 1

07

Sold

er t

wo

red

lead

sTr

im t

he

red

ou

tpu

t tr

ansf

orm

er l

ead

com

ing

th

rou

gh

th

e ru

bb

er g

rom

met

b

esid

e th

e fil

ter

cap

to

an a

pp

rop

riat

e le

ngth

and

sol

der

it to

eye

let 5

4 .

Als

o tr

im t

he r

ed l

ead

fro

m t

he r

ever

b

driv

er a

nd s

old

er it

to e

yele

t 63 .

S

TE

P 1

08

Sold

er t

hre

e ju

mp

ers

Sold

er th

e gr

een

jum

per

from

bia

s boa

rd

eyel

et E

to th

e fr

ont g

roun

ding

str

ip .

Als

o so

lder

the

gree

n ju

mp

er fr

om e

yele

t 6

to th

e fr

ont g

roun

ding

str

ip .

Sold

er t

he j

ump

er f

rom

hol

e 48

to

the

rig

ht

lug

of

the

exte

nsi

on

jac

k, a

lon

g w

ith th

e ju

mp

er fr

om th

e rig

ht lu

g of

the

spea

ker

jack

. Thi

s ju

mp

er s

hou

ld h

ave

cont

inui

ty to

eye

let 2

6 .

Sold

er th

e b

lue-

inke

d ju

mp

er fr

om h

ole

47 to

the

cent

er lu

g of

the

vib

rato

ped

al

jack

. Th

is s

ho

uld

hav

e co

nti

nu

ity

to

eyel

et 2

5 .

stew

mac

.co

m

38

©

2018

Ste

wM

ac

VIB

RAT

OPE

DA

LRE

VER

BPE

DA

LRE

VER

BO

UTP

UT

REV

ERB

INPU

TSP

EAK

ERPO

WER

GRO

UN

DFU

SEEX

TEN

SIO

N

PILO

TLA

MP

V7

5AR4

V6

6V6

V5

6V6

V4

12A

X7

V3

12A

X7

V2

12AT

7V

112

AX

7

INTE

NSI

TYSP

EED

REV

ERB

BA

SSTR

EBLE

VO

LUM

EIN

STRU

MEN

TS

21

4 3

21

87

65

4 3

21

87

65

4 3

21

87

65

6

4321

98 7 5

6

4321

98 7 5

6

4321

98 7 5

6

4321

98 7 5

OU

X

Y

O

–

U

X

Y

15

34

2

10

59

2017

67

89

11

5857

5655

5460

6162

6364

6568

6970

71 72 73 7466

67

1213

1415

1618

1921

2425

2627

3029

2831

2223

3233

3435

3740

4142

4344

4546

4748

4950

5152

5338

3936

AB

CD

FE

Keep

the

heat

er w

ires

upan

d aw

ay fr

om th

e so

cket

s

stew

mac

.co

m

39

©

2018

Ste

wM

ac

How to

REDU

CE TH

E HUM

cause

d by A

C volta

geTh

ese

gree

n he

ater

wire

s ca

rry

AC

vol

tage

that

will

cau

se h

um if

they

get

to

o cl

ose

to w

ires

that

car

ry th

e si

gnal

. The

se ti

ps

min

imiz

e th

at h

um .

Twis

t th

e w

ires

tig

htl

yTh

is r

educ

es h

um, i

n m

uch

the

sam

e th

e w

ay t

hat

two

opp

osit

e-w

ound

coi

ls w

ork

in a

hum

buc

king

pic

kup .

Ro

ute

th

em u

p a

nd

aw

ayLe

t the

se w

ires s

tick

up a

bou

t an

inch

from

the

sock

et b

efor

e b

endi

ng th

em . T

his k

eeps

the

hea

ter

wir

es f

rom

min

glin

g w

ith th

e si

gnal

wire

s .

Inst

all t

he

hea

ter

wir

esRe

view

thes

e st

eps

very

car

eful

ly b

efor

e yo

u st

art

inst

allin

g th

e he

ater

wire

s th

at

pow

er th

e he

atin

g fil

amen

ts in

the

tub

es .

It’s

imp

orta

nt to

twis

t the

se w

ires

tight

ly

toge

ther

. Thi

s is

n’t f

or lo

oks;

twis

ting

the

wire

s has

a h

um-c

ance

lling

func

tion

that

re

duce

s no

ise

in th

e am

p .

S

TE

P 1

09

Inst

all t

wo

12

" g

reen

jum

per

s

Cu

t tw

o 1

2" g

reen

ju

mp

ers

and

tw

ist

them

toge

ther

, lea

ving

ab

out

an in

ch o

f un

twis

ted

wire

on

each

sid

e . W

rap

thes

e w

ires

on

to t

he

lug

s o

f th

e p

ilot

lam

p .

Sold

er th

em in

pla

ce w

ith th

e tw

o 10

0Ω

resi

stor

s and

the

gree

n p

ower

tran

sfor

m-

er le

ads .

Rout

e th

ese

twis

ted

jum

per

s ar

ound

the

edge

of t

he c

hass

is to

reac

h so

cket

V6 .

S

TE

P 1

10

Ad

d t

wo

4"

gre

en ju

mp

ers

Cut

two

4" g

reen

jum

per

s . M

ark

one

of

thes

e ju

mp

ers

at b

oth

ends

with

a b

lack

m

arke

r so

you

can

tel

l the

m a

par

t af

ter

twis

ting

them

. Tw

ist t

hem

toge

ther

ver

y ti

gh

tly,

lea

vin

g a

bo

ut

an i

nch

fre

e at

ea

ch e

nd .

Con

nect

the

se ju

mp

ers

to t

he ju

mp

ers

from

the

pilo

t lam

p b

y tw

istin

g th

e en

ds

toge

ther

. Sol

der

the

pai

r with

the

bla

ck-

mar

ked

wire

to p

in 7

of s

ocke

t V6 .

Sold

er t

he u

nmar

ked

pai

r on

to p

in 2

of

sock

et V

6 .

Bend

thes

e w

ires s

o th

ey st

ick

stra

ight

out

fr

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SLOW


STEP 117

Install the fuseInsert the 1-amp fuse into the fuse socket from the back of the chassis . Make sure the socket cap is secure . Never use a fuse rated above 1 amp in this amplifier .

Installing the fuse, lamp, and knobs

STEP 118

Install the pilot lampInsert the pilot lamp bulb into its sock-et from the front of the chassis and twist until it locks back in place . Screw the red jewel lens over the socket .

STEP 119

Install the six control knobsTurn the shaft of each pot all the way counterclockwise to the “off” point and install the knob so the indicator line points to number 1 .

STOP!

Set the chassis on blocksSet your chassis up for final testing . A chassis stand is a great thing to have for this, because it holds the work at any angle . If you don’t have one, a couple of blocks of wood will get you by just fine .

DON’T INSTALL THE TUBES YET! DON’T PLUG THE AMP IN YET!

The next page will keep you out of trouble!


Any multimeter will work fine for the two types of tests we’re about to do: checking continuity and reading voltages . The instructions that came with your meter will be helpful .

Continuity testing is simply mak-ing sure current flows between two points successfully . Touch the meter's red lead to one end of the section being tested, and the black lead to the other end . If the continuity is good, your meter will beep or register this on the display .

Voltage testing is where you need to be careful . Some steps require the amp to be plugged in and turned on . This becomes dangerous if you’re not cautious . Respect the voltages and follow the directions, and these tests are safe and easy .

STEP 120

Perform a safe power-upAt this point, there should be no tubes installed, and the speaker should be disconnected .

Before plugging the amp in, turn the power switch to ON . Switching the amp on before the first power-up protects you from shock if a mistake in your wiring has created a short to the chassis . If this short exists, an in-dication would be that the pilot light will not turn on, since the AC current is going directly to ground .

Plug the power cord in . The pilot lamp should light .

For a few minutes, watch for smoke or unusual smells . If anything seems unusual, disconnect the power imme-diately and carefully review all your connections .

STEP 121

Test the standard AC voltageSet your multimeter to 20V AC . Check the heater voltage across pin 9 and pins 4+5 on the V1 12AX7 socket . This should read between 5-7V AC . If this reading is drastically different, unplug the amp and check your connections .

If the amp seems normal, unplug the power cord while still leaving the power switch ON .

STEP 122

Test the dangerous DC voltageThe dangerously high DC voltage that passes through the rectifier tube and the filter caps is referred to as “B+" . The next step is to test this B+ voltage .

With the amp still unplugged, in-stall the 5AR4 rectifier tube while spreading the tension clip with the other hand . Take care to position the indexing key correctly in the socket .

Plug the power cord back in . The pilot lamp should light, along with the fil-ament inside the 5AR4 rectifier tube .

Again, spend a few minutes watching for smoke or smells .

At this point, dangerous voltage is forming in the filter caps. Always discharge them before working on the circuit, even if the amp is unplugged. See how to use a snuffer stick on page 6 .

For safety, use only one hand to touch the amp during DC tests. Keep your other hand behind your back when you need to probe a com-ponent . This way, you can’t be a path between B+ voltage and ground—a mistake that would send a dangerous charge through your heart .

Set your multimeter to 500V DC and connect the negative lead to ground . Once the negative lead is secured to ground, measure the DC voltage at eyelet 54 for your B+ voltage . This should be roughly 420V DC .

Testing and troubleshooting

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Unplug the ampDanger: Remember to discharge the capacitors before working on the circuit . See how to use a snuffer stick on page 6 .

STEP 123

Test the preamp tubesWith the amp unplugged, you can install the four preamp tubes . When these tubes are installed, plug the amp back in . The pilot lamp should light up .

Let the amp warm up for a few min-utes . Again, if you get smoke or smells, unplug immediately and review your connections .

Connect your multimeter’s negative lead to ground .

Set your multimeter to 5V DC and check eyelet 70, which should read around 1 .3V .

Set the multimeter to 200V DC and check eyelet 68, this should give a reading of about 160V .

If these voltages read within about 10% of their expected values, unplug the amp .

If the reading at eyelet 68 shows no voltage or low voltage, follow this test: unplug the amp and drain the filter caps with the snuffer stick . Set your meter to read continuity . Check to see that you have properly installed the flying jumper from the “O" lug of the filter cap to eyelet 41 . You should have continuity between these two points .

STEP 124

Test the 6V6 power tubesWith the amp unplugged, install the 6V6 power tubes in sockets V5 and V6 . They have an indexing key on the center post to guide them correctly into the socket .

Plug in the speaker, footswitch, and reverb tank .

Perform these next tests with the speaker turned away from you . This is to protect your ears in case the amp starts to oscillate and squeal .

Plug the amp in . After a few moments you should hear a low hum . If the hum becomes very loud, disconnect the power immediately and review your connections .

After the amp has warmed up for a few minutes attach your multimeter’s negative lead to ground, such as the metal chassis or a grounding strip .

Set your multimeter to read 5V DC and test for voltage at eyelet 70 . This voltage should read around 1 .3V .

Set your multimeter to read 500V DC and test for voltage at pin 3 of the V6 6V6 socket . This voltage should read around 370V .

Set your multimeter to read 50V DC and test for voltage at eyelet 24 . This voltage should read around -29V (negative 29V) .

If your voltage readings are correct, plug a guitar in and play at low vol-ume . If the amp behaves as it should, keep increasing the volume . It should start to break up nicely as you increase the volume .

STEP 125

Test the reverb and tremoloIf the reverb doesn’t seem to work, try switching the cables in the reverb input and output jacks . If that doesn’t remedy the issue, check your reverb cables again for a short .

If there are any strange oscillations, squeals, or the amp seems at all unsta-ble, use a wooden chopstick to begin probing for loose connections: n from the input jacks to the eyelet boardn from the tube sockets to the eyelet boardn from the tube sockets to the front panel controls .

It usually takes just a minor wiring adjustment like resoldering a loose joint to correct this sort of distortion .

After testing all inputs, if everything seems to be operating normally, turn the amp off . You’re ready to assemble it and play it!


STEP 127

Install the chassisDischarge the capacitors so you can safely handle the amplifier . Remove all the cables from their jacks .

Slide the chassis in from the back until its front edge rests on the speaker baffle . Align the chassis straps with the holes in the top of the cabinet . Insert the mounting screws through the straps and down through the chassis . Tighten the locknuts .

Install the preamp tube shields . Fas-ten the power cord to the cable clamp on the side of the cabinet and install the back panels .

Slide the reverb tank into its bag and lay it on the floor of the cabinet . The RCA connections inside the bag should be facing front, toward the speaker baffle .

Plug in the speaker, footswitch, and reverb tank .

It's finally time to let it rip!Tips for using this ampThis amp is known for its gorgeous clean tones and luscious reverb . The vibrato isn’t as deep as is typical on Fenders because it’s tube-driven, not optocoupler-driven .

The amp’s cathodyne phase inverter creates “brown” distortion when you really start to drive the power tubes . This overdrive really pushes the mids and lows, and can become flabby if you don’t have your settings right . Use the Bass and Treble controls to dial this in . With humbuckers, try turning the bass down a bit . Give singlecoils a little more bass .

With singlecoils you can also push the reverb a little higher, which would make humbuckers become muddy .

The ’65 P-Reverb is a great pedal platform, especially for modulation and delay . Fuzz pedals will most likely need a mids-booster such as an over-drive to keep your tone from being lost in the mix, because fuzz pedals typically cut mids drastically .

Overdrive pedals on their own are great to kick in when you want to jump to the front of the mix .

Still, my favorite way to play this amp is to plug straight in and go . This amp is a classic because it has everything you need for that clean Americana tone and that drenched surfy jangle, all in one box .

Matt Clouston, StewMac

GO!GO! Tube lifeThe life span of the power tubes is affected by how hard you drive the amp . If you are overdriving the amp for hours every day, expect the power tubes to have a shorter life span .

We encourage you to experiment with different tube brands and find the brand that is most favorable to your ears and your wallet .

For questions and support, StewMac is here to help!For more than fifty years, StewMac has supplied instrument builders and repair shops . Our customer service team really knows how to help if you run into questions .

Call 800-848-2273 from 9AM–6PM Eastern time, Monday–Friday . Email: service@stewmac .com

Thanks for choosing this StewMac kit, and welcome to the world of amp building!

Final assembly


OutputGain

Negative feedback

Processing

Power

Mic level

Speaker levelLine level Line level

You don’t need to read a schematic to build this kit . But it’s fun to see how the circuit works, and to see the different subcircuits that interact to shape your sound .

Working with the tiny signal from the guitar, the amp creates the power needed to drive the speaker . The signal is affected by the gain, processing, output and power stages as it passes through the circuit .

The gain circuit increases the signal strength to line level (about 1 volt), by passing it through preamp tubes .

Inside the tube, electrons flow from a heated cathode to be received by the anode plate . Between these is a grid receiving the tiny voltage from the guitar . The guitar’s varying musical signal controls the flow of electrons to the plate . This 3-part component is called a triode .

The V1 preamp tube is the only true preamp gain stage in this circuit . A relatively cold bias, with a 1 .5K cath-ode resistor for each side, keeps the headroom high and reduces preamp distortion .

The negative feedback loop flattens and extends the amp’s frequency re-sponse, reducing distortion generat-ed in the output stage . This makes the amp’s sound cleaner and more hi-fi .

Some players disable this loop com-pletely or add a potentiometer in place of the resistor to create a “grit” control . We don’t recommend doing this, because it places unneeded stress on the output transformer .

The processing stage shapes the tone . The smallest amp of the black-panel era with both reverb and vibrato, most of the P-Reverb’s preamp tubes handle both driving and recovery of these effects . Preamp tube V2 sends the signal to the reverb, and V3 recov-ers that signal and mixes the dry and wet signals .

The first half of V4 drives the vibrato, the second half is the phase inverter . This is very different from the larger black-panel era amps, and can result in a more “brown” distortion .

The sensitive bass response can over-whelm the 10" speaker, so you might want the treble controls a little bit higher than the bass controls .

The power supply stage provides power to the other circuit stages, as well as the tube heaters and pilot light .

This circuit receives the AC power from your wall and passes it through the power transformer to create higher voltage . The electricity then goes to the rectifier, which converts it to a pulsing DC current .

This then passes through the filter cap, which contains four capacitors that filter out the pulsing to create a smooth current . As each cap smoothes a bit more, the current is also passing through resistors that lower the voltage .

As the signal from the guitar becomes more amplified, the ripple of DC current becomes less evident and the fully filtered current is sent to the most sensitive part of the amplifier, the first pre-amp tube in the Gain stage .

The output stage increases the line level signal to speaker level, which is typically 8 volts or greater .

Two 6V6 tubes drive the output trans-former . They receive the split signal, 180 degrees out of phase, amplify those signals, and send them to the output transformer to be recombined into one signal . This transformer adjusts the impedance to 8 ohms to drive the amp’s 8Ω speaker .

This amp is cathode biased, which means you don’t need to make any adjustments when replacing the power tubes . Just make sure you are replacing the power tubes with a matched pair .

cathode

plate

grid

We’ve color-coded these stages on our schematic, to show how the parts work together . Symbols for components are in the key at the bottom of the frame .

On the wiring diagram we build step-by-step in these pages, the parts are easier to recognize . But studying these color-coded stages will help you understand where each component fits into the creation of your sound .

Learning more: secrets revealed in the schematic


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It’s your amp. Your tone. You built it!

’57 MINI TWEED 5W AMP KITOne-knob titan of tone.A timeless studio darling whose tiny size hides tremendous punch and versatility .

The 5F1 circuit was meant to be a student amp but wasn’t kid stuff for long; rock’s finest guitarists hijacked it for some of the greatest songs ever recorded . Listen to Eric Clapton (“Layla”) or Joe Walsh (“Rocky Mountain Way”) while you build this amp!

Our simplest kit; the quickest way to get into amp building .

#10730 5 WATTS / 8” SPEAKER / ORIGINAL 5F1 CIRCUIT

’65 P-REVERB 15W AMP KITSparkling bright, perfect for the surf.Plug your single-coils straight in for that signature clean American tone, or go surfing with onboard effects .

The smallest member of the black-panel family to offer reverb and tremolo, this amp made its name as a jangly pop dream machine . Aficionados treasure its early low-end breakup powered by a pair of 6V6 tubes .

Listen to “Surfin’ USA” and the great sounds of Ryan Adams .

#10734 15 WATTS / 10" SPEAKER / ORIGINAL AA1164 CIRCUIT

’66 D-REVERB 22W AMP KITFamously clean, with enough guts to gig.Perfect for recording as well as performing, the D-Reverb produces stinging clarity that absolutely refuses to get lost in the mix .

One of the most popular designs ever, this amp lives in the happy middle between bright clarity and rich distortion . It excels in the studio and on the stage . While capable of crystal clear tones at good volume, you can push this one into beautifully saturated, play-sensitive distortion .

It’s all here: clarity, distortion, and rectifier tube sag .

#10737 22 WATTS / 12" SPEAKER / ORIGINAL AB763 CIRCUIT

H OU RS : 6

D I F F I C U LTY

H OU RS : 1 2

D I F F I C U LTY

H OU RS : 8

D I F F I C U LTY

H OU RS : 16

D I F F I C U LTY

’59 TWEED 15W AMP KITDirty little devil that shaped guitar history.With mysteriously fat saturated tone, this little monster makes it easy to achieve seismic distortion .

This amp’s 5E3 circuit is an enigma: Why do the controls on the channel you’re NOT using make your tone so great? The answer: Who cares? This is one of the greatest tone monsters ever created! Listen to Neil Young’s Rust Never Sleeps while building this kit .

Our most popular amp kit and a great learning experience .

#10731 15 WATTS / 10” SPEAKER / ORIGINAL 5E3 CIRCUIT

StewMac ICON KITS teach you the world of amp building, then turn you loose with amazing hand-built tone machines!


’62 BRIT-PLEX 45W AMP KITThe original British showstopper.This amp started a revolution . It’s been rocking the world for over 50 years, and we still can’t get enough .

Favored by blues and rock players for exceptional sustain and rich creamy tone, the ’62 Brit-Plex is chock-full of harmonic gain, yet it still stays articulate and even a little crispy . Put this head on a classic 4x10 cab and watch out!

While building, listen to Gary Moore’s “Still Got The Blues .”

#10736 45 WATTS / ORIGINAL 1962 CIRCUIT

’66 BRIT-74X 18W AMP KITLeave your half-stack at home.Born in London, this little blues blaster earns its living every night, gigging in clubs across the USA .

Launched in 1966, this amp quickly became a low-wattage holy grail . This is a stripped down blues machine: two channels, one tone knob, no master volume . Buckle up and go where this gritty beast takes you! It comes with a footswitch to kick in the onboard tremolo .

Get the plexi tone without blowing the roof off the joint!

#10732 18 WATTS / 12" SPEAKER / ORIGINAL 1965 CIRCUIT

’81 BRIT-800 50W AMP KITThis hairy monster lives to shred.The defining British circuit that dominated the ’80s .

This 50W giant created your favorite heavy rock and metal albums . Used by Slayer and Pixies, and recorded on early Metallica albums, this circuit produces that screaming guitar tone that your mother despises . With solid-state rectification there’s no sag, and the distortion created by this circuit is way more about treble than mids or bass .

Listen while building: Smashing Pumpkins’ Siamese Dream .

#10735 50 WATTS / ORIGINAL 1981 CIRCUIT

’64 REVERB UNIT KITReverb you can’t get from a pedal.This is the unit that put the waves in surf music! Looks like an amp, sounds like a beach party .

This tube-driven reverb tank relies on good ol’ physics for a perfect effect . Your guitar signal travels along two large suspended springs to produce the reverb that launched the iconic surf sound . This isn't a pocket-sized digital simulation; this is the real deal!

Listen to Dick Dale’s “Misirlou” while doing this easy build .

#10733 ORIGINAL 6G15 CIRCUIT

H OU RS : 1 2

D I F F I C U LTY

H OU RS : 1 2

D I F F I C U LTY

H OU RS : 16

D I F F I C U LTY

H OU RS : 8

D I F F I C U LTY

Beginner-tested. Pro quality.StewMac ICON KITS are fun to build, with friendly instructions to guide you and loads of info to add to your knowledge.


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StewMac®

I C O N K I T S



5AR4(GZ34)

6V6 6V612AT7(ECC81)

12AX7(ECC83)

V7 V6 V5 V2 V1

12AX7(ECC83)

12AX7(ECC83)

V4 V3

#10734


StewMac®

I C O N K I T S



5AR4(GZ34)

6V6 6V612AT7(ECC81)

12AX7(ECC83)

V7 V6 V5 V2 V1

12AX7(ECC83)

12AX7(ECC83)

V4 V3

#10734

Cut this label on the dotted line with a razor knife and metal straightedge .Fasten it inside the cabinet using thinned wood glue or contact cement .

The duplicate copy below is included as a backup .



tools + ideas for guitarmakingStewMac

21 N . Shafer St ., Athens, OH 45701800-848-2273 stewmac .com

©2018 StewMac . All rights reserved .#i10734 Updated October, 2018

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’65 P-REVERB 15W

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