XORbot is a fairly simple noisebox synthesizer using logical operations to generate sounds.
There is no MIDI key tracking, though there is a gate and volume envelope that can be enabled and triggered by MIDI notes.
XORbot has two oscillators, one of which is essentially used only as an amplitude modulation source. The other (main) oscillator acts as a clock for the actual sound generation process, so neither oscillator is actually heard in the audio output, but it is probably easiest to think of them as you would a standard oscillator in any other synth.
Clock: controls the frequency of the main oscillator, which in turn drives the logical operations responsible for sound generation.
ModOsc (knob): controls the frequency of the Mod oscillator.
Fine: fine tuning for the Clock and Mod oscillators.
Mod [X]: both the Clock and Mod oscillators can have a modulation source assigned to their pitch, with a bipolar amount control.
Reset: sets the reset mode for a stepped component of the audio generation “circuit.” The details aren’t important, each mode just sounds a bit different.
Mode: controls the number of logical operations involved in the audio generation. Again, the details are unimportant, each mode is just a bit different.
Mix Mode: controls how the different elements of the audio generator are mixed.
ModOsc (button): turns the Mod oscillator on and off.
XD: turns on a sort of “circuit bend” that changes the sound.
Pretty standard synth stuff, in a VA style.
Type: 12dB or 24dB lowpass, or 12dB highpass or bandpass
Mod: modulation source for the filter cutoff/center frequency.
Drive: how hard the filter input is driven.
Cut: filter cutoff (if LP or HP)/center (if BP) frequency.
Res: filter resonance/Q.
Mod: filter modulation amount.
Modulated delay effect, the output of which can be fed back to the filter input.
Time: base delay time.
Feed: delay feedback (internal).
Feed 2: how much the delayed signal (including internal feedback) is fed back to the filter input.
Mod: delay time modulation source and amount.
Rnd Rt: rate of random modulation applied to the delay time (note that each stereo channel has its own individual random source).
Rnd Amt: amount of random delay time modulation.
Mix: wet/dry mix for the delay effect.
Mostly pretty standard stuff, there are 3 LFO’s (Low Frequency Oscillators), each with rate and level controls. These can also be synced to the host’s BPM, in which case the “Rate” knob has no effect, and the rate is set using the pop-up list control.
There are also two Sample and Hold (S&H) units, which work in a similar fashion.
The “Combiners” are the one bit that may be unfamiliar. These combine two modulation sources (chosen via the pop-up lists) using one of several mathematical or logical operations (again, chosen via list). Note that Combiner 2 can also use the first Combiner as a source.
XORbot is mostly intended to be an “always on” sort of noisebox, with the output controlled via Volume knob or mixer channel, but there is also an option to use MIDI notes as a gate source for a VCA. With the MIDI Gate on, XORbot’s output can be triggered by MIDI notes, though incoming notes will have no effect on oscillators’ frequencies or anything else, other than the LFO key triggers, if on. There is a simple envelope on this VCA, with Attack (Atk) and Release (Rls) controls, as well as a control for velocity sensitivity (Vel). The MIDI channel XORbot responds to can also be set.
Patch List: gives the list of patches (presets) in a pop-up list, and allows you to pick one.
Patch name display: displays the name of the currently chosen patch, and allows you to change it.
Patch Menu: contains all the other relevant items for loading/saving patches, etc.
FSA Freeware License
Copyright (c) 2021 Kevin Breidenbach
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to use the Software without restriction. This does not include the rights to publish, distribute, sublicense, and/or sell copies of the Software.
THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
FSA plugins made with SynthEdit make use of modules from the following developers:
RoyTech (Lee Loque) – https://groups.io/g/synthedit/message/9459
Elena – http://www.elenadomain.it/listing/SE/
Time Domain Modules – https://tdmodules.wordpress.com/
QTN – https://qtnmodules.blogspot.com/
Thanks to Jeff McClintock for creating SynthEdit – http://www.synthedit.com/
VST and VST3 are trademarks of Steinberg Media Technologies AG