Engl Rockmaster 20 E307, Metalmaster 20 E304, RockMaster 20 E302, Metalmaster 20 E309 Operator's Manual

E304/E309

Metalmaster 20

Operator´s Manual

The ENGL RockMaster amp and the ENGL MetalMaster amp are purpose-designed for performance
and voiced to meet specific sound characters in order to offer the guitar player a perfect platfom for
diverse tonal genres. Both the combo and head versions of each amp model come in exceedingly
compact housings. These amplifier series are perfect for small gigs, home or studio recording, and
practicing at lower volumes without sacrificing tone. In fact, because they are endowed with hip
features such as a balanced Line Out with speaker simulation and a built-in Power Soak with four
variable power stages, these amps are well-suited for a wide range of diverse applications. The Master
knob lets you dial in precisely the desired amount of power amp saturation.
Two EL84 pentode power tubes produce the amp's trademark tone, while two ECC83 double triode
preamp tubes provides authentic tube sound.
These amp models offers plenty of variety for the tone connoisseur courtesy of their two channels
Clean and Lead: while the MetalMaster amp is featuring oodles of front-end overdrive during Lead
mode, the RockMaster's Gain range is perfectly tuned to deliver a broad spectrum of medium preamp
saturation in Clean and Lead channels; nevertheless the Lead Gain level completely suffices for playing
typical fat Lead solos.
Another clear-cut feaure is a specially voiced Mid Boost (RockMaster amp) or Mid Scoop (MetalMaster
amp) switch that shapes those midrange frequencies that matter so much to electric guitar tone.
Moreover these amps also come loaded with a bevy of convenient sound-sculpting features designed
to make your musical life easier and more rewarding, including a built-in reverb system and a serial FX
Loop, both features switchable on the fly via footswitch, likewise channel switching and Mid Shape.
And, although the four foot-switchable features afford you even greater flexibility to shape sounds
spontaneously, handling these remains an exercise in convenience and simplicity.
You'll find guidelines on care and maintenance of tube amps and details for the Power Soak handling
in certain places of this manual. Please read and heed these before operating your amp.
You'll also come across boxes shaded grey throughout the manual. These are located between the
descriptions of the amp's functions and contain handy tips on the preceding function. All critical
information pertaining to the operation of this amp is preceded by "NOTE" or "CAUTION." Please pay
particular attention to these safety tips.
The ENGL team wishes you all the best—may you and your amp enjoy a "harmonically rich" future
together!

Front

1 Input: ¼" unbalanced input jack. Plug your guitar in here using a shielded cord.
2 Clean Gain: Gain control for the Clean channel. This knob determines the preamp's input sensitivity

when the Clean channel is selected and, by extension, the preamp signal's saturation level. It and the
Master (11) knob determine the Clean channel's volume.
A tip from the designer: Here's how this knob's settings relate to the type of guitar pickup.
If you are using single-coils, the preamp will start breaking up at about 6, and at around the 4 or 5
with more powerful humbuckers or an active pickup. If you want a pristine clean sound,
back off the Clean Gain knob setting.
The power amp provides a moderate amount of headroom, so be sure to choose a relatively low
Master knob setting (lower than 5) if you wish to avoid any kind of break-up. Even in Clean mode,
you can push both the amp's preamp and power amp hard enough to overdrive the signal.
CAUTION: Extremely high gain and volume levels can produce powerful feedback. Avoid feedback
squeals; they can lead to hearing loss and damage speakers! At higher volumes, back off the Gain
and Treble levels in order to prevent unchecked feedback!
3 Lead Gain: Gain control for the Lead channel. This Control knob determines input sensitivity when
the Lead is active. Use it to dial in the desired amount of preamp saturation level.
A tip from the designer: You can achieve a moderate preamp saturation or overdrive if you prefer
for typical rock riffs or for rhythm work with Lead Gain knob settings prior to the position 5; ideally
in the range between 1 to 4, depending on the output of the guitar pickup and the amp type.
Higher Lead Gain control settings produces a remarkably rich sustain and a singing lead tone,
perfectly suited for playing solos and lead guitar for example. I would only recommend very high
Gain levels at moderate volume to get additional sustain. In other words, you should avoid Lead Gain
knob settings beyond the position 6 at high output power in order to prevent interaction between
guitar and speakers that possibly causes undesirable feedback.

CLEAN GAIN LEAD GAIN BASS MIDDLE TREBLE LEAD VOLUME

CLEAN

LEAD

MASTER

STAND BY POWER

REVERB

MID

SHAPE

INPUT

0

1

2

3

4

5

6

7

8

9

10

0

1

2

3

4

5

6

7

8

9

10

0

1

2

3

4

5

6

7

8

9

10

0

1

2

3

4

5

6

7

8

9

10

0

1

2

3

4

5

6

7

8

9

10

0

1

2

3

4

5

6

7

8

9

10

0

1

2

3

4

5

6

7

8

9

10

0

1

2

3

4

5

6

7

8

9

10

R

1

2

3 4 9 10

5 6 7 8 11 12 1413

CAUTION: Extremely high gain and volume levels in Lead mode can produce powerful feedback.
Avoid feedback squeals; they can lead to hearing loss and damage speakers! At higher volumes,
back off the Gain and Treble levels in order to prevent unchecked feedback!

4 Bass: Bottom end voicing control of the preamps´s passive EQ.
5 Middle: Mid-range voicing control of the preamps´s passive EQ.
6 Treble: Upper range voicing control of the preamps´s passive EQ.

Tips and info from the designer: To help you get acquainted with the amp's fundamental sounds,
I recommend that you set all tone controls to the center position; that is, to around 5.
Two channels with different gain structures (Clean and Lead) share the same voicing section here.
This is why the passive three-band tone controls have been tuned to deliver optimum results even
with settings remaining unchanged when switching channels.
Note the range of these passive controls is narrower than that of comparable active EQ systems.
If you want to dial in very soft lead, blues, or jazzy clean sounds, try setting the Treble knob
between position 4 and 6 at the RockMaster amp. For more aggressive riffs or funk-approved tone,
try a knob position between 5 and 8 at the MetalMaster amp.
7 Reverb: Reverb intensity knob. Twist it to adjust the amount of reverb for Clean and Lead.
Turn the Reverb control knob clockwise to increase the effect's intensity. The signal remains
completely dry when the knob is set to the 0 position or if Reverb is deactivated via a footswitch.
You can switch the reverb unit on and off using a footswitch connected to jack 17.
The reverb unit is always on if you do not plug a footswitch into jack 17.
Note: A digital processor generates the reverb effect.
8 Lead Volume: Volume control for the Lead channel (pre-FX loop, influences the Send level during
Lead mode). The red LED above the channel switching selector (10) indicates Lead operating
mode. Use this knob to dial in the desired balance of levels between the Lead and Clean channels.
9 Mid Shape function: Mid Boost (RockMaster amp) or Mid Scoop (MetalMaster amp)
This voicing feature influences specific midrange frequencies in the preamps´s EQ section. The
sound-shaping button operates globally, affecting both channels. When activated, frequencies
between 300 Hz and 2 KHz are
boosted varyingly strong: Mid Boost, RockMaster amp;
cut at a varyingly strong degree: Mid Scoop, Metal Master amp.
The LED above the button lights up to indicate Mid Shape (Mid Boost or Mid Scoop) is activated.
The Mid Shape (Mid Boost or Mid Scoop) sound feature may also be switched using a footswitch
connected to jack (18).The button (9) on the amp's front panel is disengaged when you switch the
Mid Shape (Mid Boost or Mid Scoop) function via footswitch (18).
For more details see the chapter 18 !
A tip from the designer:
The Mid Shape (Mid Boost or Mid Scoop) button voices specific midrange frequencies that are
instrumental in fine-tuning a guitar's sound.
This tone-shaping option is remotely controllable via footswitch, so you can adapt the amp's
fundamental sound on the fly, say to better support rhythm guitar work, singing leads,
and slashing power chords.
10 Lead/Clean: This channel switching button selects the Clean channel or the Lead channel.
Press it to activate the Lead channel. The red LED above the button lights up to indicate Lead mode
is active. This function can also be activated via the respective footswitch connected to jack 18.
Once a footpedal is connected, the channel selector switch is deactivated.

11 Master: This master volume knob controls the power amp's output (it is located post FX Loop).
12 Power On: this LED lit when the amp is powered up.
13 Stand By: Power amp standby switch: Use this switch to silence ("down" position) the amp when

you take a break. The amp's tubes stay warm, which means that it is ready to roll immediately
when you switch it back to full power. The standby switch is also well-suited for muting the amp
for brief breaks, for instance when you're switching guitars.
A tip from the designer: I suggest you get into the habit of using standby during short breaks.
In this mode, current is not piped through the power tubes, so they don't get as hot (due to the
lack of anode dissipation) and are spared considerable wear. The amp is ready to run when you
flip the Standby switch because the tubes are already warm and don't require time to heat up.
For breaks of 20 minutes and longer, I recommend that you switch the amp off in order
to conserve energy.
13 Power: AC power on/off. The power on LED (12) indicates when the amp is switched on.
Please note: ensure that the Stand By switch (13) is set to Stand By ("down" position) before you
switch the amp on. Let the tubes heat up for about 30 seconds before you activate the power amp.
This procedure spares the tubes.
CAUTION: After an extended period of operation and higher ambient temperatures the amps's
chassis can become very hot, therefore avoid touching the rear panel surface!

Rear Panel

15 Mains Connector (AC Power Inlet; IEC - C14 connector)

Plug the mains cord in here. For European models, use a standard non-heating equipment
connector cable.
CAUTION: Make sure you use an intact mains line cord with a grounded plug!
Before you power the amp up, ensure the voltage value printed on the label next to
the mains socket is the same as the current of the local power supply or wall outlet.
Please also heed the guidelines set forth in the separately included pamphlet,
Instructions for the Prevention of Fire, Electrical Shock and Injury.
16 Mains Fuse Box: The rear chamber contains the mains fuse and in the front chamber, a spare fuse.
CAUTION: ALWAYS make sure replacement fuses are of the same type and have the same ratings
as the original fuse! Please refer to the fuse ratings table.
17 Footswitch Reverb; FX Loop off/on: Use this ¼" Stereo jack to connect a conventional footswitch
with two switching functions, for example, the ENGL Z-4 (2 x off/on - Single Pole Single Throw or
SPST for short). This type of footswitch lets you switch Reverb off or on and FX Loop off or on.
One of the two switches engages the internal Reverb the other enables or bypasses FX Loop.
The Reverb system and the FX Loop are activated by default if you do not connect a footswitch
to this jack. Note also that a footswitch may be equipped with LEDs indicating the given switching
status. Each of the two switches is provided with about 10 milliamperes of current, which suffices
to power a standard LED. The jack's mono terminal (the tip) switches the Reverb off or on,
and the stereo terminal (the ring) switches FX Loop off and on.
For pin assignments, see "Wiring of Principal Connectors".
18 Footswitch Clean/Lead; Mid Shape (Mid Boost oder Mid Scoop): Use this ¼" Stereo jack to
connect a conventional footswitch with two switching functions, for example, the ENGL Z-4
(2 x off/on - Single Pole Single Throw or SPST for short). This type of footswitch lets you access the
two channels and Mid Shape (collective term for Mid Boost and Mid Scoop).
One of the two switches activates Clean or Lead; the other controls the Mid Shape function
Mid Boost, RockMaster amp: boosts a certain mid frequency range when activated;
Mid Scoop, MetalMaster amp: cuts ta certain mid frequency range when activated;
Plugging a footswitch into this jack disables onboard channel (10) and Mid Shape (9) switching.
Note also that a footswitch may be equipped with LEDs indicating the given switching status.
Each of the two switches is provided with about 10 milliamperes current, which suffices to power
a standard LED. The jack's mono terminal (the tip) selects Clean or Lead, while the stereo terminal
(the ring) switches Mid Shape. For pin assignments, see "Wiring of Principal Connectors".
A Tip from the designer: If you want to control the amplifier via a MIDI system, use jacks 17, 18
and a looper or MIDI switcher (such as the ENGL Z11-S.A.C). Use two stereo ¼" cords to connect
the optionally available ENGL MIDI Switcher Z11-S.A.C.. You can then preset the four switching
functions Clean/Lead, Mid Shape, Reverb off/on and FX Loop off/on via the switcher, store your
custom switching setups as different MIDI programs, and activate the presets via a MIDI board
such as the ENGL Z-12. For more details, see the remote control options on the last page.
19 FX Loop Send: Connect the serial FX Loop output to a signal processor's input/return jack using
the shortest possible shielded cord equipped with 1/4" plugs. The FX Loop can be controlled
remotely (on/off function) via a footswitch connected to jack 17 (for details refer to chapter 17).
In the signal path, the FX Loop is located post preamp and pre the power amp Master knob.
20 FX Loop Return: Connect the FX Loop input to a signal processor's output/send jack using the
shortest possible shielded cord equipped with 1/4" plugs. The FX Loop can be controlled remotely
(on/off function) via a footswitch connected to jack 17 (for details refer to chapter 17).
In the signal path, the FX Loop is located post preamp and pre the power amp Master knob.
Note: Inserting a ¼" jack plug into the Return port interrupts the circuit between the preamp
and power amp.

Footswitch

Tube Guitar Amplifier

RockMaster

20

Combo: Type E302

Head: Type E307

MetalMaster 20

Combo: Type E304

Head: Type E309

Amp-Design by

Horst Langer

ENGL Amps

Made In Germany

CAUTION !

!

REPLACE FUSE

ONLY WITH SAME

TYPE AND RATING !

R

Clean

/

Lead

Mid Shape

DO NOT OPEN !

RISK OF ELECTRIC SHOCK !

DO NOT EXPOSE THIS

EQUIPMENT TO

RAIN OR MOISTURE !

FX Loop

Send Return

8 - 16
Ohms

full power

Frequency

Comp.

Line Out
Balanced

Reverb

FX Loop

off

/

on

8 Ohms

serial

to jack A

Poweramp Output

8 - 16
Ohms

Power Soak

A: connect one

8 or 16 ohms speaker
to this output jack for
full output power.
Output C is disabled
once a plug is connected
to output jack A.

B: connect an additional

8 ohms speaker to
a 8 ohms speaker
connected to output A.

C: connect one

8 or 16 ohms speaker
to this output jack when
employing the Power Soak.

A B C

17

19

24

18

2115

16

20 22 23