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bkFX - BlauKraut Effects suite
Reference Guide (in progress, incomplete)
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bkChannelTool
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A utility plugin which combines various functionality related to processing of stereo signals. 

* Delay L/R: delay of left/right channel in ms. A negative value introduces plugin latency which is useful to e.g. align audio from different tracks in DAWs that lack a dedicated track delay parameter.
* Delay Link: links the delay values of both channel. When active, "Delay L" determines value of both channels.
* Width: control stereo width by blending between mid channel and side channel. 0% -> Mono, 100% -> stereo, 200% -> only side channel

bkChorus
========

* Type: set the basic algorithm
	- Chorus: classic two-voice chorus
    - Chorus+: four-voice chorus
    - Ensemble: chorus effect from classic string synths (taken over from bkEnsemble)
    - Dimension: popular modern stereo expansion effect. This effect avoids obvious modulation character by modulating amplitude rather than length of delay taps
    - Dimension+: like Dimension, but using 4 delay taps instead of 2.

bkClipper
=========

A versatile soft clipper/waveshaper. The output of the clipper is processed by a built-in d.c. blocker.

* Knee: allows to smoothly vary between hard clipping (0%) and soft clipping (100%)
* Asymmetry: 0% results in purely symmetric clipping, +/-100% results in clipping of the upper/lower halfwave of the input signal.

bkComp
======

A simple yet effective downward/upward compressor

* Thresh Down: threshold for downward compression
* Thresh Upward: threshold for upward compression. This value is relative to Thresh Down,
  so if e.g. both thresholds are set to -6 dB, the effective upward compression threshold is -12 dB.
  Setting Thresh Upward to the minimum value disables upward compression entirely.
* Ratio: amount of gain reduction when exceeding either threshold
* Attack: attack time, i.e. how quickly gain is reduced when input signal exceeds Thresh Down
* Decay: attack time, i.e. how quickly unity gain is recovered when input signal falls below Thresh Down
* Look-ahead: time that input detector can look ahead of gain reduction state. A non-zero value allows
  to respond to fast transients without distorting the signal, but will also introduce latency into the
  audio path.
* Output: output gain adjustment. Since the compressor applies automatic gain compensation,
  a value of 0 dB may lead to an output signal that is louder than 0 dB, see warning below.

WARNING: Inappropriate choice of parameter values can lead to loud audio bursts that may damage your ears or
gear! This behavior greatly depends on the characteristics of the source signal to be processed.

bkCrusher
=========

A digital "bit crusher" effect which combines sample word size reduction with sample rate reduction to yield these nasty digital artifacts which sometimes are just what you are looking for.

bkDelay
=======

A versatile Stereo delay effects. Provides classic digital/analog/tape-style/ping pong/modulated delay, chorus, flanger and other effects. Also well suited for artificial stereo image generation or stereo widening.

* Delay Base: sets the base unit for delay times. Use "100ms" for fixed time and "1/8 note" for musical time dependent on project tempo.
* Delay Factor L/R: Actual delay time = Delay Factor x Delay Base. Can be automated for pitch shifting effects.
* Delay Link: links the Delay Factor values of both channels. When active, "Delay Factor L" determines value of both channels.
* Mod Stereo: The LFO output for modulating delay time is inverted on one channel to yield nice stereo effects.
* Width: Control stereo width of delay signal by blending between mid channel and side channel. 0% -> Mono, 100% -> stereo, 200% -> only side channel.
         Settings > 100% useful for mono-compatible stereo widening effects.

bkFixedFilter
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A simple highpass (HP)/lowpass (LP) filter with adjustable slope (6, 12 and 24 dB/oct). Typical applications are d.c. blocking and removing "harshness" (i.e. over-emphasized highs). The filter is designed to allow basic sound shaping while preserving a natural sound rather than an obvious "filtered" sound. As thus, there is no embedded nonlinearity that would introduce additional coloration of the sound. HP is a Butterworth design while for the LP a design with a smoother frequency response around the corner frequency was chosen in order to avoid ringing artifacts. As the name suggests, this plugin is *not* suited for automation/fast modulation. LP filter uses "decramping" technique to minimize warping of frequency response near the Nyquist frequency without oversampling. 

* Type: filter type (LP = lowpass, HP = highpass)
* Order: filter order determines slope of filter attenuation in dB per octave (db/oct)
* Fequency: corner frequency.

bkFreqSplitter
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Splits the input signal in upto 3 frequency bands which are available on separate outputs for further processing.

bkDualFilter
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A dual multi-mode filter controlled by a Low Frequency Oscillator (LFO). The filter modes are based on the algorithms of BlauKraut's Charlatan virtual analog synth plugin which emulate classic analog circuits. Finally, the LFO can also control signal amplitude to obtain a tremolo effect.

* Filter Type:
    - LP2 / BP2 / HP2 / Notch2: 2-pole (12 db/oct) Sallen-Key filter architecture as found in some classic analogue synths
    - LP4 / BP4 / HP4: 4-pole (24 db/oct) Transistor ladder filter architecture as found in some classic analogue synths
    - AP4 is a cascade of four 1-pole allpass stages. To achieve classic phase shifter effects, the dry signal has to mixed with the filtered (wet) signal.
    - Comb+/-: digital comb filter with positive or negative feedback. Similarly to AP4, a proper comb filter effect requires the dry signal to be mixed with the filtered signal.
* Offset: frequency offset between filter 1 and 2, symmetrically (in logarithmic scale) spread around the frequency set by "Cutoff" parameter.
* Filter Mod: depth of filter cutoff modulation by LFO in octaves. The "Filter Cutoff" parameter determines the highest frequency of the modulation range.
* LFO Stereo: The LFO output for modulating delay time is inverted on one channel to yield nice stereo effects.

bkPitch
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A lo-fi pitch shifting effect. This does not attempt to provide natural results but produces lots of artifacts which greatly color the sound and give it "character".

bkReverb
========

A versatile, true-stereo, HQ algorithmic reverberator at a laughable CPU footprint. Designed to cover a large ground from tiny natural acoustic ambiences to larger-than-live walls of reverb.

Paramters:
* Size: determines the apparent size of the simulated room. A large room size leads to a sparse echo density.
* Time: the duration of the reverb tail (RT60 time)
* Diffuse: controls the strength of the input diffusion, i.e. blurring the input signal over time before feeding in to the reverb. High diffusion is most beneficial for percussive signals in order to avoid obvious discrete echoes in the reverb tail. On the other hand, if you're aiming for a reverb effect that is invisible and seamlessly blends with the dry signal, a lower diffusion value usually gives better results. Also, high diffusion can cause unnatural ringing artifacts in some cases.
* Mod: modulates delay lengths of late reverb to give a lush, chorus-like effect. This is a very common feature found in classic reverb units which was originally mainly included to mitigate "metallic ringing" artifacts in the tail. Being an artificial effect not found in real spaces, it is recommended to use sparingly when you want natural results, e.g. for acoustic instruments. It is therefore best used for synth, especially pad sounds with a long reverb tail.
* Damp: causes high frequencies to decay faster than low frequencies in the reverb tails as happening in real spaces.

