Operator`s manual
5 Bottom
Alters the EQ by boosting the low end range; the Bottom feature affects the Clean Channel & the 
Lead Channel.
A tip from the designer:
If you want to ladle an extra helping of bottom-end oomph on specific sounds, I recommend that you 
activate the Bottom button. At very high Volume settings, it can be an advantage to deactivate this 
function for a more focused, crisper tone with precise definition in the lo end frequency range.
6 Bass 
Bottom end voicing control of the preamps´s passive EQ.
7 Middle  
Mid-range voicing control of the preamps´s passive EQ.
8 Treble
Upper range voicing control of the preamps´s passive EQ.
TIP´s 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 or 12 o'clock position. 
For high Gain Lead sounds, your best bet is to turn the Treble knob well down to prevent the pickups 
and speakers from interacting at hi levels and generating feedback (the recommended setting is 
somewhere in the 10 to 2 o'clock range).
Since the Treble and Presence control knobs sweep through different frequency ranges and influence 
the signal at different places in the amp's internal signal chain, you can dial in different combinations 
of treble and presence settings to come up with many interesting sonic variations.
9 Lead Volume
Volume control for the Lead channel (pre-FX loop, influences the Send level). The red LED above the 
channel switching selector (11) indicates Lead operating mode. 
Use this knob to dial in the desired balance of levels between the Lead and Clean channels.
10 Mid Boost
This voicing feature operates globally, affecting both channels by boosting specific midrange 
frequencies when activated. The LED above the button lights up to indicate Mid Boost is activated. It 
may also be switched using a footswitch connected to jack (20). When a footswitch is plugged in, the 
front panel Mid Boost button is disabled.
A tip from the designer:
Mid Boost targets and shapes specific midrange bands crucial in voicing 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. 
With a handy MIDI switcher such as the ENGL Z-11, you can assign Clean/Lead channel switching, 
Master A/B, Mid Boost and the FX Loop off/on function to different MIDI presets and control these 
switching and sound-shaping functions remotely in any configuration using a MIDI footboard.
11 Clean / Lead
Channel selector pushbutton for Clean and Lead modes, red LED indicate Lead mode; This function 
can also be activated via the respective footswitch connected to jack 21.
Once a footpedal is connected, the channel selector pushbutton is deactivated.
12 Master A
Master volume A for power amp output (located post FX loop). The red LED next to the knob lights 
up when this knob determines the master volume level. Master A/B switching can be accessed via a 
footswitch connected to jack 21 (e.g. ENGL Z-4).
13 Master B
Master volume B for power amp output (located post FX loop). The green LED next to the knob lights 
up when this knob determines the master volume level. Master A/B switching can be accessed via a 
footswitch connected to jack 21 (e.g. ENGL Z-4).
Tip from the Designer:
You can dial in different levels for Master A and Master B, assign these settings to any channel, and 
access them directly via the two channel switches on the Z-4 foot controller. This gives you a range of 
alternatives that you can apply to different playing styles and musical genres to great dramatic effect. 
What's more, you can use the Clean channel for rhythm or cleaner lead lines and the Lead channel's 
overdriven preamp stage for power chords and soloing, and go from soft to loud at the touch of a 
button. Beyond that, you can also broaden the volume and tonal ranges by working your guitars' 
volume knob. If your arsenal includes MIDI gear - for instance, the Z-11 ENGL MIDI Switcher in 
combination with a MIDI Footswitch (e.g ENGL Z-9, Z-12, Z-15) - you may use the amp's Master A/B 
circuit to swiftly and conveniently set the power amp's volume to two different levels, and then access 
these volume presets in combination with preamp voicing features such as Mid Boost.
14 Presence
This control shapes the hi frequency response in the power amp stage and affects both channels.










