Menu->Model FX gets you to the Effects Chain Editor where you can effect parameter values, using a familiar stomp-box UI. You can add, delete and reorder effects in the chain. There are three special items in the chain that are not audio effects, Perform, always first in the chain, which are the Performance Settings, Guitar, always second in the chain, which is the guitar model, and the Amplifier, always last in the chain, which is the output unit. Everything else is an audio effect.
Some effects are stereo, and some are mono, and some have special ordering constraints, which are described below.
The Guitar consists of six physically modeled strings (nylon to steel), three body resonances, two pickups (single or double coil), guitar/sitar/tambura bridges, and other added features.
Guitar distortion effects nonlinearly transform the sound wave to generate higher harmonics and intermodulation products.
The Mud Face distortion unit is special in that it is implemented internal to the Guitar, which is why it must always be positioned immediately next to the Guitar in the Effects Chain.
Guitar distortion effect simulating the analog circuit of an early distortion stomp-box including a dual-diode nonlinearity and shelf filter.
Guitar distortion effect simulating the analog circuit of a classic distortion stomp-box using a filtered dual-diode and separate tone stage. Because this appears to be the most popular of the three distortion units in GeoShred, and relatively expensive computationally, it offers oversampling in the Expert menu.
The Feedback effect simply throws a feedback signal from its point in the Effects Chain to the guitar strings.
Volume control that is moveable to anywhere within Effects Chain
Autowah: Wah pedal driven by signal level
Envelope follower - generates an amplitude envelope triggered by signal level that is then multiplied by the signal to shape its amplitude. You can think of it as an AutoWah for amplitude.
Dynamic Range Compressor - more compression means a flatter amplitude envelope, giving a more sustained sound
Second-order low-pass, high-pass, or band-pass filter.
The Moog "Voltage Controlled Filter" (VCF) provides a fourth-order low-pass, high-pass, or band-pass filter. It is based on the classic circuit by Robert A. Moog.
A Parametric Equalizer provides very general and precisely controllable equalization using elementary filter sections such as shelf and peaking equalizer filters.
The Echo unit creates echoes, as you might expect.
The Multi-Tap Echo unit is four echo units in one. It is like four Trail-Blazer Echo units, except that there is no Looping, Scrubbing, or Warping, and there is individual Stereo Panning on each of the four echo channels.
The Chorus effect makes copies of its input sound and remixes them to the stereo field using differently modulated delays, thus simulating a chorus of nearly identical sound sources.
The Chorus output is always stereo, while its input may be either mono or stereo. To minimize CPU usage, place the Chorus at the point in your Effects Chain where the Effects are mono to the left and stereo to the right.
The flanger effect impresses uniformly spaced sweeping notches on the sound spectrum. It accomplishes this using a variable comb filter, which works by mixing the input sound with a variably delayed-and-scaled copy of the input. Unlike the phaser, the flanger notches are uniformly spaced on a linear frequency scale, and there can be many more of them at low cost.
A stereo Flanger effect.
The Tremolo Effect is made using periodic Volume Modulation
A reverberator creates a sense of space. Classic guitar amps use a "spring reverb", which is one or more metal springs through which the sound propagates and disperses. GeoShred uses a more modern design from the field of Computer Music based on delay lines and Schroeder allpass filters
The Wiz Verb is always stereo. It is normally placed last in the Effects Chain.
The amplifier and speaker-cabinet modify your sound like typical guitar amplifiers.