Amp and Cabinet
The amplifier and speaker-cabinet modify your sound like typical guitar amplifiers.
Parameters:
Stereo > Mono Switch
The output sound is normally stereo, but you'll want a mono output when the sound guy only gives you one channel (bummer). In mono mode, the left and right channels each contain the same mono mix-down.
Mute Switch
The mute switch can be used to turn off all audio out. It will also stop all computation of the model. This is extremely useful for pure MIDI-OUT presets where there is no need to run the model.
Volume
This volume control is after all the effects. It is the one to use for setting overall level without affecting distortion levels and other nonlinear effects. It goes up to 11.
Cabinet Resonances
The speaker cabinet in your guitar amp primarily limits the bandwidth to a typical guitar-amp range. It also provides subtle cabinet resonances giving the cabinet its characteristic sound. Guitar amps typically use 12-inch speakers, which is the biggest part of the sound, but the cabinet resonances are also important.
Tone Stack Parameters
The Bass, Middle, and Treble knobs comprise what is called the tone stack. The basic circuit for the tone stack is the same in most guitar amps, but different amps use different values for its resistors and capacitors. Here we have three cases to choose from, spanning a range of classic amps.
Normalize
Compensates for tone-stack level changes. The tone stack is a passive circuit (no power supply) that is modeled very accurately. As a result, it causes a drop in signal level relative to the Bypass setting. Tapping Normalize adjusts for this "insertion loss". The new gain is stored in the Tonestack Gain parameter.
Bass
This sets your "bass" level. It interacts with the Middle and Treble controls. Listen carefully and watch the Frequency Response display on the amplifier grill-cloth to see precisely what it does.
Middle
This sets the "middle" level between the bass and treble ranges. It interacts with the Bass and Treble controls.
Treble
Sets the "treble" level - interacts with the Bass and Middle controls.
Expert Parameters
Under the Expert menu, there are more Amplifier/Cabinet controls:
Preset Final Volume (Expert)
This "Preset Final Volume" is after all the effects, just like the Amplifier Volume. It is identical to Amplifier Volume except that it can be set to any value. It's a good one to use "behind the scenes" for normalizing your presets to a standard level at the same Volume setting (see the audio level meter in the Trace Window).
Tone Stack Expert Parameters
Under the Expert menu, there are additional controls for the Tone Stack:
Tonestack Gain
This scales the tonestack output. It is manipulated automatically when Tonestack AutoGain Enable is turned on. Otherwise you can set it manually.
Bass T60
Adjust the Bass T60 to obtain more or less smoothing of the Bass-knob changes during performance.
Middle T60
Adjust the Middle T60 to obtain more or less smoothing of the Middle-knob changes during performance.
Treble T60
Adjust the Treble T60 to obtain more or less smoothing of the Treble-knob changes during performance.
VibroPan Controls (Expert)
The VibroPan controls enable a left/right pan based on finger vibrato. It's a unique effect. In order to use this effect VibroPan Enable must be turned on and VibroPan Center Angle needs to "Subscribe to KeyX". Vibro Pan Center Angle Delta sets the spread of the pan. Vibro Pan Center Angle Smoothing controls the glide-time for pan changes. Vibro Pan Pitch Sensitivity is a depth for the pan's response to KeyX.