GBG120 Tube Amp

SOLO

Solo Switch

The SOLO function boosts your sound for leads and solos. The volume level of the boosted signal can be tweaked using the Volume knob right to the SOLO switch.

Depending on the SFX switch, the SOLO FX LOOP (SFX) will be activated automatically when SOLO is switched on.

MIDI Controllable Send Control Change #89 (CC #89).
Values: 0 = OFF, 127 = ON.

GATE

Gate Switch

Connects the chanel to the gate system with global potentiometer control

Each channel on the amplifier has dedicated switch that activates the gate for that channel.

LC

Low-Cut Switch

Cuts the lows below 200 Hz with a soft curve

This optional filter helps tame unwanted low-end rumble, particularly beneficial when using high-gain pedals or playing at high volumes.

GAIN

Gain Switch

Adds more aggressive gain

This switch provides a subtle increase in gain when engaged, adding a touch of warmth and edge to your clean tone, perfect for bluesy leads or pushing the clean channel into a breakup territory.

VINT

Vintage Switch

Warmer, old school sound

This switch selects between two variations of the crunch character. Experiment to find the perfect balance between a tighter, more focused crunch or a looser, more vintage-flavored breakup.

GAIN

Gain Switch

Adds more aggressive gain

Similar to the clean channel, this switch injects a touch more gain to the crunch character, pushing it towards a more saturated and aggressive territory, ideal for heavier rock and blues solos.

VINT

Vintage Switch

Warmer, old school sound

Just like in Channel 2, this switch offers two distinct distortion flavors. One might provide a tighter, more modern high-gain character, while the other delivers a more classic, scooped midrange distortion reminiscent of 70s and 80s rock.

GAIN

Gain Switch

Adds more aggressive gain

Crank it up! This switch injects a significant gain boost to the distortion channel, perfect for achieving those ultra-saturated, face-melting tones for the heaviest genres.

LB

Low-Boost Switch:

A tight boost for the lows below 200 Hz. Present on CH4 only

This optional switch adds a low-end boost to the extreme distortion, ideal for achieving a massive, earth-shaking bottom end for heavy riffs and djent styles.

MOD

Modern Switch

Modifies the tube distortion to more modern style

This switch engages a modifier circuit that further sculpts the extreme distortion character. A scooped midrange for a scooped metal tone, a tighter focus for aggressive rhythm playing.

PWR

Power Switch (& MIDI Setup)

In OFF position the button is flush with its housing, in ON position it is recessed.

By pressing the button CH 1 / SOLO+FX OFF, a MIDI Program Change #4 (PC #4) is sent to the device. This switches to CH 1 and turns off SOLO and FX. This can be used to initialize GBG120 when remote controlling it via a MIDI controller.

ZUTA GBG120 Remote Control & Manual v1.0.0

FX

FX Switch

Engage the primary FX loop

This switch activates the FX chain. When engaged (illuminated), the signal passes through the FX loop, allowing you to add effects like reverb, chorus, or delay. When disengaged, the signal bypasses the FX loop.

MIDI Controllable Send Control Change #90 (CC #90).
Values: 0 = OFF, 127 = ON.

LINE

Line Switch

Toggle between line and instrument level. Affects only the Line/Instrument and In/Out sockets

This toggle switch allows you to choose the input source for the jacks located on the rear panel of the amplifier.

LINE switch light off: This is the default setting. When selected, the rear panel INSTREUMENT IN jack is active, but the amplifier prioritizes the instrument connected to the main input jack on the front panel.

LINE switch light on: the rear panel LINE IN jack become active for connecting line-level audio sources. Line-level signals are typically stronger than instrument-level signals and may come from keyboards, external processors, or recording equipment.

Important Note: This switch only affects the functionality of the jacks on the rear panel. The main input jack on the front panel is always operational for instrument connection regardless of the LINE switch setting.

HB

High-Boost Switch

A tight boost for the highs above 2 kHz

MB

Mid-Boost Switch

A bell curve boost for the mids, peak at 1 kHz

PMB

Presence Mids-Boost Switch

A dedicated control that emphasizes the middle frequencies.

When this switch is turned on, the range of control through the Presence potentiometer changes, so instead of high, high mid tones are highlighted.

PFX

Parallel FX Switch

Toggle between serial and parallel connection for FX

This switch determines FX working mode, default serial mode, pushed in parallel mode.

SFX

SOLO FX Switch

Engage the secondary SOLO function dependent FX Loop

The SOLO FX LOOP switch enable the serial SFX loop to be activated or deactivated via the SOLO function. This chain might be dedicated to modulation effects like phaser, flanger, or tremolo.

GBG

GBG Switch

A special distortion typical for the Gothenburg sound

GBG button activates DIODE bridging for the channels 2-3-4, adding more compression and clipping to the signal.