Use the amp controls
The amp settings include controls for the input gain, presence, and master output. The Gain knob is located to the left in the knobs section, the Presence and Master knobs are to the right, and the Output slider is at the lower-right edge of the window.
Adjust the amp controls
Gain knob: Turn to set the amount of pre-amplification applied to the input signal. This control affects specific amp models in different ways. For example, when you use the British Amp, the maximum gain setting produces a powerful crunch sound. When you use the Vintage British Head or Modern British Head, the same gain setting produces heavy distortion, suitable for lead solos.
Presence knob: Turn to adjust the ultra-high frequency range—above the range of the Treble control. The Presence knob affects only the output (Master) stage.
Master knob: Turn to set the output volume of the amplifier signal sent to the cabinet. For tube amplifiers, increasing the Master level typically produces a compressed and saturated sound, resulting in a more distorted and louder signal.
WARNING: Because high Master knob settings can produce an extremely loud output that can damage your speakers or hearing, start with a low Master knob setting and then slowly increase it.
Output slider or field: Drag to set the final output level of Amp Designer.
Note: The slider is replaced with a field in the small interface.