Kurzweil ALGORITHMS2 User manual

FXAlgs #724-6, 728: Distortion
Algorithm Reference-94
FXAlgs #724-6, 728: Distortion
FXAlg #724 Ñ Mono Distortion
FXAlg #725 Ñ MonoDistort + Cab
FXAlg #726 Ñ MonoDistort + EQ
FXAlg #728 Ñ StereoDistort+EQ
Small distortion algorithms
Allocation Units: 1 for Mono Distortion; 2 for MonoDistort + Cab; 2 for MonoDistort + EQ;
3 for StereoDistort + EQ
Mono Distortion sums its stereo input to mono, performs distortion followed by a hipass filter and sends the result
as centered stereo.
Block diagram of Mono Distortion
MonoDistort + EQ is similar to Mono Distortion except the single hipass filter is replaced with a pair of second-order
hipass/lowpass filters to provide rudimentary speaker cabinet modeling. The hipass and lowpass filters are then
followed by an EQ section with bass and treble shelf filters and two parametric mid filters.
Block diagram of MonoDistort + EQ
StereoDistort + EQ processes the left and right channels separately, though there is only one set of parameters for
both channels. The stereo distortion has only one parametric mid filter.
Block diagram of StereoDistort+EQ
Distortion
L Output
R Output
L Input
R Input
R Input
L Input
Distortion
R Output
L Output
EQ
Cabinet
Distortion EQ
Distortion EQ R Output
L OutputL Input
R Input

FXAlgs #724-6, 728: Distortion
Algorithm Reference-95
MonoDistort + Cab is also similar to Mono Distortion except the hipass is replaced by a full speaker cabinet model.
There is also a panner to route the mono signal between left and right outputs. In MonoDistort + Cab, the distortion
is followed by a model of a guitar amplifier cabinet. The model can be bypassed, or there are eight presets which
were derived from measurements of real cabinets. (See descriptions of FXAlgs #729-732 in this book for more
information.)
Block diagram of MonoDistort + Cab
The distortion algorithm will soft clip the input signal. The amount of soft clipping depends on how high the
distortion drive parameter is set. Soft clipping means that there is a smooth transition from linear gain to saturated
overdrive. Higher distortion drive settings cause the transition to become progressively sharper or ÒharderÓ. The
distortion never produces hard or digital clipping, but it does approach it at high drive settings. When you increase
the distortion drive parameter you are increasing the gain of the algorithm until the signal reaches saturation. You
will have to compensate for increases in drive gain by reducing the output gain. These algorithms will not digitally
clip unless the output gain is over-driven.
Input/Output Transfer Characteristic of Soft Clipping at Various Drive Settings
Signals which are symmetric in amplitude (they have the same shape if they are inverted, positive for negative) will
usually produce odd harmonic distortion. For example, a pure sine wave will produce smaller copies of itself at 3,
5, 7, etc. times the original frequency of the sine wave. In the MonoDistort + EQ, a dc offset may be added to the
signal to break the amplitude symmetry and will cause the distortion to produce even harmonics. This can add a
ÒbrassyÓ character to the distorted sound. The dc offset added prior to distortion gets removed at a later point in
the algorithm.
L Input
Distortion
R Input
Cabinet
Filter Pan
L Output
R Output
Output
Input

FXAlgs #724-6, 728: Distortion
Algorithm Reference-96
Parameters - Mono Distortion:
PAGE 1
MonoDistort + Cab:
PAGE 1
MonoDistort + EQ:
PAGE 1
PAGE 2
StereoDistort+EQ:
PAGE 1
Wet/Dry 0 to 100%wet Out Gain Off, -79.0 to 24.0 dB
Dist Drive 0 to 96 dB
Warmth 16 to 25088 Hz
Highpass 16 to 25088 Hz
Wet/Dry 0 to 100%wet Out Gain Off, -79.0 to 24.0 dB
Dist Drive 0 to 96 dB
Warmth 16 to 25088 Hz Cab Bypass In or Out
Cab Preset Basic
Wet/Dry 0 to 100%wet Out Gain Off, -79.0 to 24.0 dB
Dist Drive 0 to 96 dB
Warmth 16 to 25088 Hz dc Offset -100 to 100%
Cabinet HP 16 to 25088 Hz Cabinet LP 16 to 25088 Hz
Bass Gain -79.0 to 24.0 dB Treb Gain -79.0 to 24.0 dB
Bass Freq 16 to 25088 Hz Treb Freq 16 to 25088 Hz
Mid1 Gain -79.0 to 24.0 dB Mid2 Gain -79.0 to 24.0 dB
Mid1 Freq 16 to 25088 Hz Mid2 Freq 16 to 25088 Hz
Mid1 Width 0.010 to 5.000 oct Mid2 Width 0.010 to 5.000 oct
Wet/Dry 0 to 100%wet Out Gain Off, -79.0 to 24.0 dB
Dist Drive 0 to 96 dB
Warmth 16 to 25088 Hz
Cabinet HP 16 to 25088 Hz Cabinet LP 16 to 25088 Hz

FXAlgs #724-6, 728: Distortion
Algorithm Reference-97
PAGE 2
Wet/Dry The amount of distorted (wet) signal relative to unaffected (dry) signal.
Out Gain The overall gain or amplitude at the output of the effect. For distortion, it is often
necessary to turn the output gain down as the distortion drive is turned up.
Dist Drive Applies a boost to the input signal to overdrive the distortion algorithm. When
overdriven, the distortion algorithm will soft-clip the signal. Since distortion drive will
make your signal very loud, you may have to reduce the Out Gain as the drive is
increased.
Warmth A lowpass Þlter in the distortion control path. This Þlter may be used to reduce some of
the harshness of some distortion settings without reducing the bandwidth of the signal.
Cab Bypass The guitar ampliÞer cabinet simulation may be bypassed. When set to ÒInÓ, the cabinet
simulation is active; when set to ÒOutÓ, there is no cabinet Þltering. [MonoDistort + Cab]
Cab Preset Eight preset cabinets have been created based on measurements of real guitar ampliÞer
cabinets. The presets are Basic, Lead 12, 2x12, Open 12, Open 10, 4x12, Hot 2x12, and Hot
12. See description of FX Algs #729-732 for more information. [MonoDistort + Cab]
Highpass Allows you to reduce the bass content of the distortion content. If you need more
Þltering to better simulate a speaker cabinet, you will have to choose a larger distortion
algorithm. [Mono Distortion]
MonoDistort + EQ and StereoDistort+EQ
Cabinet HP A hipass Þlter which controls the low-frequency limit of a simulated loudspeaker
cabinet.
Cabinet LP A lowpass Þlter which controls the high-frequency limit of a simulated cabinet.
Bass Gain The amount of boost or cut that the bass shelving Þlter should apply to the low
frequency signals in dB. Every increase of 6 dB approximately doubles the amplitude of
the signal. Positive values boost the bass signal below the speciÞed frequency. Negative
values cut the bass signal below the speciÞed frequency.
Bass Freq The center frequency of the bass shelving Þlter in intervals of one semitone.
Treb Gain The amount of boost or cut that the treble shelving Þlter should apply to the high
frequency signals in dB. Every increase of 6 dB approximately doubles the amplitude of
the signal. Positive values boost the treble signal above the speciÞed frequency. Negative
values cut the treble signal above the speciÞed frequency.
Treb Freq The center frequency of the treble shelving Þlter in intervals of one semitone.
Mid Gain The amount of boost or cut that the mid parametric Þlter should apply in dB. Every
increase of 6 dB approximately doubles the amplitude of the signal. Positive values
boost the signal at the speciÞed frequency. Negative values cut the signal at the
speciÞed frequency.
Mid Freq The center frequency of the mid parametric Þlter in intervals of one semitone. The boost
or cut will be at a maximum at this frequency.
Mid Wid The bandwidth of the mid parametric Þlter may be adjusted. You specify the bandwidth
in octaves. Small values result in a very narrow Þlter response. Large values result in a
very broad response.
Bass Gain -79.0 to 24.0 dB Treb Gain -79.0 to 24.0 dB
Bass Freq 16 to 25088 Hz Treb Freq 16 to 25088 Hz
Mid Gain -79.0 to 24.0 dB
Mid Freq 16 to 25088 Hz
Mid Width 0.010 to 5.000 oct

FXAlg #727: PolyDistort + EQ
Algorithm Reference-98
FXAlg #727: PolyDistort + EQ
Eight-stage distortion followed by equalization
Allocation Units: 2
PolyDistort + EQ is a distortion algorithm followed by equalization. The algorithm consists of an input gain stage,
and then eight cascaded distortion stages. Each stage is followed by a one-pole LP filter. There is also a one pole
LP in front of the first stage. After the distortion there is a 4-band EQ section: Bass, Treble, and two Parametric Mids.
Block diagram of PolyDistort + EQ
Distort
Curve 1 Curve 2
Distort
Curve 3
Distort Distort
Curve 4
Curve 5
Distort Distort
Curve 6
Curve 7
Distort Distort
Curve 8
L Input
R Input
L Output
R Output
Dry
Dry
Wet
LP1 LP2
LP3 LP4
LP5 LP6
LP7 LP8
Bass Treble Mid1 Mid2
Parametric
Dist Drive
LP0

FXAlg #727: PolyDistort + EQ
Algorithm Reference-99
PolyDistort is an unusual distortion algorithm which provides a great number of parameters to build a distortion
sound from the ground up. The eight distortion stages each add a small amount of distortion to the sound. Taken
together, they can produce a very harsh heavy metal sound. Between each distortion stage is a lopass filter. The
lopass filters work with the distortion stages to help mellow out the sound. Without any lopass filters the distortion
will get very harsh and raspy.
Stages of distortion can be removed by setting the Curve parameter to 0. You can then do a 6, 4, or 2 stage distortion
algorithm. The corresponding lopasses should be turned off if there is no distortion in a section. More than 4 stages
seem necessary for lead guitar sounds. For a cleaner sound, you may want to limit yourself to only 4 stages.
Once you have set up a distorted sound you are satisfied with, the Dist Drive parameter controls the input gain to
the distortion, providing a single parameter for controlling distortion amount. You will probably find that you will
have to cut back on the output gain as you drive the distortion louder.
Post-distortion EQ is definitely needed to make things sound right. This should be something like a guitar speaker
cabinet simulator, although not exactly, since we are already doing a lot of lopass filtering inside the distortion itself.
Possible EQ settings you can try are Treble -20 dB at 5 kHz, Bass -6 dB at 100 Hz, Mid1, wide, +6 dB at 2 kHz, Mid2,
wide, +3 dB at 200 Hz, but of course you should certainly experiment to get your sound. The Treble is helping to
remove raspiness, the Bass is removing the extreme low end like an open-back guitar cabinet (not that guitar
speakers have that much low end anyway), Mid1 adds enough highs so that things can sound bright even in the
presence of all the HF roll-off, and Mid2 adds some warmth. Your favorite settings will probably be different.
Boosting the Treble may not be a good idea.
Pre-distortion EQ, available on the KDFX Studio INPUT pages, is also useful for shaping the sound. EQ done in
front of the distortion will not be heard as simple EQ, because the distortion section makes an adjustment in one
frequency range felt over a much wider range due to action of the distortion. Simple post-EQ is a bit too obvious for
the ear, and it can get tiring after a while.
Parameters:
PAGE 1
PAGE 2
PAGE 2
Wet/Dry 0 to 100%wet Out Gain Off, -79.0 to 24.0 dB
Dist Drive Off, -79.0 to 48.0 dB
Curve 1 0 to 127% Curve 5 0 to 127%
Curve 2 0 to 127% Curve 6 0 to 127%
Curve 3 0 to 127% Curve 7 0 to 127%
Curve 4 0 to 127% Curve 8 0 to 127%
LP0 Freq 16 to 25088 Hz
LP1 Freq 16 to 25088 Hz LP5 Freq 16 to 25088 Hz
LP2 Freq 16 to 25088 Hz LP6 Freq 16 to 25088 Hz
LP3 Freq 16 to 25088 Hz LP7 Freq 16 to 25088 Hz
LP4 Freq 16 to 25088 Hz LP8 Freq 16 to 25088 Hz

FXAlg #727: PolyDistort + EQ
Algorithm Reference-100
PAGE 4
Wet/Dry This is a simple mix of the distorted signal relative to the dry undistorted input signal.
Out Gain The overall gain or amplitude at the output of the effect. For distortion, it is often
necessary to turn the output gain down as the distortion drive is turned up.
Dist Drive Applies gain to the input prior to distortion. It is the basic Òdistortion driveÓ control.
Anything over 0 dB could clip. Normally clipping would be bad, but the distortion
algorithm tends to smooth things out. Still, considering that for some settings of the
other parameters you would have to back off the gain to -48 dB in order to get a not very
distorted sound for full scale input, you should go easy on this amount.
Curve
n The curvature of the individual distortion stages. 0% is no curvature (no distortion at
all). At 100%, the curve bends over smoothly and becomes perfectly ßat right before it
goes into clipping.
LP n Freq These are the one-pole lopass controls. LP0 Freq handles the initial lopass prior to the
Þrst distortion stage. The other lopass controls follow their respective distortion stages.
With all lopasses out of the circuit (set to the highest frequency), the sound tends to be
too bright and raspy. With less distortion drive, less Þltering is needed. If you turn off a
distortion stage (set to 0%), you should turn of the lopass Þlter by setting it to the highest
frequency.
Bass Gain The amount of boost or cut that the bass-shelving Þlter should apply to the low-
frequency signals in dB. Every increase of 6 dB approximately doubles the amplitude of
the signal. Positive values boost the bass signal below the speciÞed frequency. Negative
values cut the bass signal below the speciÞed frequency.
Bass Freq The center frequency of the bass shelving Þlter in intervals of one semitone.
Treb Gain The amount of boost or cut that the treble-shelving Þlter should apply to the high-
frequency signals in dB. Every increase of 6 dB approximately doubles the amplitude of
the signal. Positive values boost the treble signal above the speciÞed frequency. Negative
values cut the treble signal above the speciÞed frequency.
Treb Freq The center frequency of the treble shelving Þlter in intervals of one semitone.
Mid Gain The amount of boost or cut that the mid parametric Þlter should apply in dB. Every
increase of 6 dB approximately doubles the amplitude of the signal. Positive values
boost the signal at the speciÞed frequency. Negative values cut the signal at the
speciÞed frequency.
Mid Freq The center frequency of the mid parametric Þlter in intervals of one semitone. The boost
or cut will be at a maximum at this frequency.
Mid Wid The bandwidth of the mid parametric Þlter may be adjusted. The bandwidth is speciÞed
in octaves. Small values result in a very narrow Þlter response. Large values result in a
very broad response.
Bass Gain -79.0 to 24.0 dB Treb Gain -79.0 to 24.0 dB
Bass Freq 16 to 25088 Hz Treb Freq 16 to 25088 Hz
Mid1 Gain -79.0 to 24.0 dB Mid2 Gain -79.0 to 24.0 dB
Mid1 Freq 16 to 25088 Hz Mid2 Freq 16 to 25088 Hz
Mid1 Width 0.010 to 5.000 oct Mid2 Width 0.010 to 5.000 oct

Tube Amp/Distortion/Delay Combinations
Algorithm Reference-101
Tube Amp/Distortion/Delay Combinations
FXAlg #729: TubeAmp<>MD>Chor
FXAlg #730: TubeAmp<>MD>Flan
FXAlg #731: PolyAmp<>MD>Chor
FXAlg #732: PolyAmp<>MD>Flan
Mono distortion circuits in combination with moving delays,
and a stereo chorus or stereo flange
Allocation Units :3 each
Each of these four algorithms offer a flexible chain of effects designed primarily for guitar processing. Each chain
offers a different combination of a 3-band tone control, tube-amp distortion drive, poly-amp distortion drive,
cabinet simulation, chorus, flange, and a generic moving delay. The entire algorithm is monaural with the exception
of the final chorus or flange at the end of each chain, which have one input and a stereo output.
At the beginning of each chain is a 3-band tone control authentically re-creating the response in many guitar
preamps based on real measurements collected by Kurzweil engineers. It is adjusted with the Bass Tone, Mid Tone,
and Treb Tone controls with values ranging from 0 to 10 commonly found on many guitar amps. The flattest
frequency response is obtained by setting Mid Tone to 10.0, and both Bass and Treb Tone controls to 0.0.
The tone controls are integrated with one of two types of preamp drive circuits: TubeAmp and PolyAmp. The
TubeAmp faithfully models the response and smooth distortion caused by overloading a vacuum tube circuit.
PolyAmp is closely related to the PolyDistort algorithm offering a brighter sound quality with more sustain. The
amount of distortion is controlled by adjusting the Tube Drive or Poly Drive parameter. High frequency energy
caused by distortion can be rolled off by using the Warmth parameter.
Following the distortion drive element is a cabinet simulator. The cabinet simulator models the responses of various
types of micÕd guitar cabinets. The preset can be selected using the Cab Preset parameter. The following is the list
of cabinet presets and their descriptions:
Basic Flat response from 100 Hz to 4 kHz with 4th order roll-offs (24dB/oct) on each end
Lead 12 Open back hard American type with one 12Ó driver
2x12 Closed back classic American type with two 12Ó drivers
Open 12 Open back classic American type with one 12Ó driver
Open 10 Open back classic American type with one 10Ó driver
4x12 Closed back British type with four 12Ó drivers
Hot 2x12 Closed back hot rod type with two 12Ó drivers
Hot 12 Open back hot rod type with one 12Ó driver

Tube Amp/Distortion/Delay Combinations
Algorithm Reference-102
The cabinet can by switched on or off with the Cab In/Out parameter. The Cab Pan parameter adjusts the final pan
position of the cabinet at the output of the algorithm, but this does not affect the cabinet signal fed into the final
stereo flange or chorus. If Ch Wet/Dry or Fl Wet/Dry is set to 100%, this pan control will not have any audible affect
since the entire output of the cabinet is fed into the flange or chorus instead of the algorithm output.
At the end of the chain is either a chorus or a flange controlled by parameters beginning with ÒChÓ or ÒFlÓ
respectively. The chorus and flange have mono inputs and stereo outputs. Each is a standard KDFX single tap dual
channel chorus (see FXAlg #150) or flange (see FXAlg#154) with independent controls for left and right channels
found in many other 1-PAU combination algorithms. The Ch Wet/Dry or Fl Wet/Dry control determines the final
output mix of the algorithm. When set at 0%, only the cabinet simulator output is fed to the output of the algorithm.
At 100%, only the output of the chorus or flange is heard. Left/right balance specifically for the chorus or flange can
be adjusted with the Out Bal control.
In addition, there is a generic monaural moving delay segment. Its parameters begin with the letters ÒMDÓ. The
moving delay is flexible enough that it can serve as a chorus, flange, or straight delay. For more detailed
information, refer to the section describing the Dual MovDelay and Quad MovDelay algorithms (FXAlgs #715-716).
As implemented in these four algorithms, it can be inserted either before the tone controls (PreDist), or after the
distortion drive (PostDist), or bypassed altogether. This is selected with the MD Insert parameter. Also provided is
the MD Wet/Dry parameter that mixes the output of the moving delay circuit with its own input to be fed into the
next effect in the chain.
TubeAmp<>MD>Chor with moving delay inserted PreDist
Blend Moving
Delay Tone Cab Simulator
Chorus
Pan
Input Bal
MD Wet/Dry
Ch Wet/Dry
Ch Out Bal Out Gain
L Output
R Output
L Input
R Input
Tube
Amp

Tube Amp/Distortion/Delay Combinations
Algorithm Reference-103
TubeAmp<>MD>Chor with moving delay inserted PostDist
Parameters:
PAGE 1
PAGE 2 (TubeAmp algs)
PAGE 2 (PolyAmp algs)
In/Out In or Out Out Gain Off; -79.0 to 24.0 dB
Input Bal -100 to 100%
Tube Drive Off; -79.0 to 60.0 dB
Warmth 16 to 25088 Hz
Bass Tone 0.0 to 10.0
Mid Tone 0.0 to 10.0 Cab In/Out In or Out
Treb Tone 0.0 to 10.0 Cab Preset Open 12, ...
Cab Pan -100 to 100%
Poly Drive 0.0 to 60.0 dB
Warmth 16 to 25088 Hz
Bass Tone 0.0 to 10.0
Mid Tone 0.0 to 10.0 Cab In/Out In or Out
Treb Tone 0.0 to 10.0 Cab Preset Open 12, ...
Cab Pan -100 to 100%
Blend Moving
Delay
Tone Cab
Simulator
Chorus
Pan
Input Bal
MD Wet/Dry
Ch Wet/Dry
Ch Out Bal Out Gain
L Output
R Output
L Input
R Input
Tube
Amp

Tube Amp/Distortion/Delay Combinations
Algorithm Reference-104
PAGE 3
PAGE 4 (Chorus algs)
PAGE 4 (Flange algs)
In/Out Toggles the entire effect on or off. When off, the input signal is passed.
Input Bal Adjusts the ratio of left and right algorithm inputs to be summed into the monaural
signal that is processed by the effect. 0% blends equal amount of left and right. Negative
values blend increasing amounts of left, while positive values blend increasing amounts
of right.
Out Gain The overall gain or amplitude at the output of the effect.
Bass Tone, Mid Tone, Treb Tone Adjusts the 3 bands of the tone control integrated with the distortion drive circuit.
Flattest response is obtained by setting Mid Tone to 10.0, and both Bass Tone and Treb
Tone to 0.0.
Tube Drive, Poly Drive Adjusts the gain into each distortion circuit. Higher values produce more distortion.
Warmth Adjusts a 1-pole (6dB/oct) lopass Þlter applied after distortion.
Cab In/Out Turns the cabinet simulator on or off.
Cab Preset Selects the preset cabinet type.
Cab Pan Adjusts the output pan position of the cabinet simulator signal that is mixed at the
output of the algorithm. Note that when Ch Wet/Dry or Fl Wet/Dry is set to 100%, no
signal from the cabinet is mixed directly to the output, so this parameter has no affect.
MD Insert Selects where in the signal chain the moving delay is to be. PreDist places it before the
distortion and tone circuit. PostDist places it between the distortion circuit and cabinet
simulator, and Bypass takes it completely out of the path.
MD Wet/Dry Adjusts the ratio of the moving delay output mixed with its own input to be fed to the
next effect in the chain.
MD Insert Post Dist, ... MD Delay 0.0 to 1000.0 ms
MD Wet/Dry 0 to 100% MD LFOMode Flange, ...
MD LFORate 0.00 to 10.00 Hz
MD LFODpth 0.0 to 200.0%
MD Fdbk -100 to 100%
Ch Rate L 0.01 to 10.00 Hz Ch Rate R 0.01 to 10.00 Hz
Ch Depth L 0.0 to 100.0 cts Ch Depth R 0.0 to 100.0 cts
Ch Delay L 0 to 720 ms Ch Delay R 0 to 720 ms
Ch Fdbk L -100 to 100% Ch Fdbk R -100 to 100%
Ch PtchEnv Triangle or Trapzoid
ChWet/Dry 0 to 100% Ch Out Bal -100 to 100%
Fl Rate 0 to 32 bts Fl Tempo System; 1 to 255 BPM
Fl Xcurs L 0 to 230 ms Fl Xcurs R 0 to 230 ms
Fl Delay L 0 to 230 ms Fl Delay R 0 to 230 ms
Fl Fdbk L -100 to 100% Fl Fdbk R -100 to 100%
Fl Phase L 0 to 360 deg Fl Phase R 0 to 360 deg
Fl Wet/Dry 0 to 100% Fl Out Bal -100 to 100%

Tube Amp/Distortion/Delay Combinations
Algorithm Reference-105
MD Delay Adjusts the delay time for the moving delay circuit, which is the center of LFO
excursion.
MD LFOMode Adjusts the LFO excursion type. In Flange mode, the LFO is optimized for ßange effects
and LFO Dpth adjusts the excursion amount. In ChorTri and ChorTrap modes, the LFO
is optimized for triangle and trapezoidal pitch envelopes respectively, and LFO Dpth
adjusts the amount of chorus detuning. In Delay mode, the LFO is turned off leaving a
basic delay. LFO Rate and LFO Dpth in Delay mode are disabled.
MD LFORate Adjusts the LFO speed for the moving delay circuit.
MD LFODpth In Flange LFO mode, this adjusts an arbitrary LFO excursion amount. In ChorTri and
ChorTrap modes, this controls the chorus detune amount. In delay mode, this is
disabled.
MD Fdbk Adjusts the level of the moving delay circuit output signal fed back into its own input.
Negative values polarity-invert the feedback signal.
Ch Wet/Dry, Fl Wet/Dry Adjusts the ratio of ßange or chorus signal and the cabinet simulator signal fed to
the output of the algorithm. 0% feeds only the cabinet simulator to the output bypassing
the Þnal chorus or ßange. 100% feeds only the ßange or chorus to the output.
Ch Out Bal, Fl Out Bal Adjusts the left/right output balance of the chorus or ßange signal. Negative values
balance toward the left while positive values balance toward the right.

FXAlg #733: VibChor+Rotor 2 ¥ FXAlg #734: VibChor+Rotor 4
Algorithm Reference-106
FXAlg #733: VibChor+Rotor 2 ¥
FXAlg #734: VibChor+Rotor 4
Vibrato/chorus, through optional distortion, into rotating speaker
Allocation Units: 2 for VibChor+Rotor 2; 4 for VibChor+Rotor 4
The VibChor+Rotor algorithms contain multiple effects designed for the Hammond B3¨emulation (KB3 mode).
These effects are the Hammond¨vibrato/chorus, amplifier distortion, and rotating speaker (Leslie¨). Each of these
effects may be turned off or bypassed, or the entire algorithm may be bypassed.
Block diagram of VibChor+Rotor
The first effect in the chain is the Hammond vibrato/chorus algorithm. The vibrato/chorus has six settings which
are the same as those used in the Hammond B3: three vibrato (V1, V2, V3) and three chorus (C1, C2, C3) settings. In
VibChor+Rotor 4, the vibrato chorus has been carefully modeled after the electro-mechanical vibrato/chorus in the
B3. The vibrato/chorus in VibChor+Rotor 2 uses a conventional design, which has been set to match the B3 sound
as closely as possible, but does not quite have the same character as the VibChor+Rotor 4 vibrato/chorus.
In VibChor+Rotor 4 an amplifier distortion algorithm follows the vibrato/chorus. See the section in this book on
FXAlg #724 for more information about the distortion algorithm.
Finally, the signal passes through a rotating speaker routine. The rotating speaker has separately controllable
tweeter and woofer drivers. The signal is split into high and low frequency bands and the two bands are run
through separate rotors. The upper and lower rotors each have a pair of virtual microphones which can be
positioned at varying positions (angles) around the rotors. An angle of 0°is loosely defined as the front. You can
also control the levels and left-right panning of each virtual microphone. The signal is then passed through a final
lowpass filter to simulate the band-limiting effect of the speaker cabinet.
Pan
Pan
Pan
Pan
L Output
R Output
Mic Levels Out Gain
Cabinet
Cabinet
Rotator
Rotator
Vibrato/
Chorus
Distortion
(Optional)
L Input
R Output

FXAlg #733: VibChor+Rotor 2 ¥ FXAlg #734: VibChor+Rotor 4
Algorithm Reference-107
Rotating speaker with virtual microphones
For the rotating speakers, you can control the crossover frequency of the high and low frequency bands (the
frequency where the high and low frequencies get separated). The rotating speakers for the high and low
frequencies have their own controls. For both, the rotation rate, the effective driver size and tremolo can be set. The
rotation rate sets how fast the rotating speaker is spinning. The effective driver size is the radius of the path followed
by the speaker relative to its center of rotation. This parameter is used to calculate the resulting Doppler shift of the
moving speaker. Doppler shift is the pitch shift that occurs when a sound source moves toward or away from you
the listener. In a rotating speaker, the Doppler shift will sound like vibrato. As well as Doppler shift, there will be
some acoustic shadowing as the speaker is alternately pointed away from you and toward you. The shadowing is
simulated with a tremolo over which you can control the tremolo depth and ÒwidthÓ. The high-frequency driver
(rotating horn) will have a narrower acoustic beam width (dispersion) than the low-frequency driver, and the
widths of both may be adjusted. Note that it can take up to one full speaker rotation before you hear changes to
tremolo when parameter values are changed. Negative microphone angles take a longer time to respond to tremolo
changes than positive microphone angles.
Acoustic beams for (i) low frequency driver and (ii) high frequency driver.
You can control resonant modes within the rotating speaker cabinet with the Lo and Hi Resonate parameters. For
a realistic rotating speaker, the resonance level and delay excursion should be set quite low. High levels will give
wild pitch shifting.
negative anglespositive angles
(i) (ii)

FXAlg #733: VibChor+Rotor 2 ¥ FXAlg #734: VibChor+Rotor 4
Algorithm Reference-108
Parameters:
PAGE 1
PAGE 2
PAGE 3
PAGE 4
In/Out When set to ÒInÓ, the algorithm is active; when set to ÒOutÓ the algorithm is bypassed.
Out Gain The overall gain or amplitude at the output of the effect. For distortion, it is often
necessary to turn the output gain down as the distortion drive is turned up.
VibChInOut When set to ÒInÓ the vibrato/chorus is active; when set to ÒOutÓ the vibrato/chorus is
bypassed.
Vib/Chor This control sets the Hammond B3¨ vibrato/chorus. There are six settings for this effect:
three vibratos ÒV1Ó, ÒV2Ó, ÒV3Ó, and three choruses ÒC1Ó, ÒC2Ó, ÒC3Ó
Roto InOut When set to ÒInÓ the rotary speaker is active; when set to ÒOutÓ the rotary speaker is
bypassed.
Dist Drive Applies a boost to the input signal to overdrive the distortion algorithm. When
overdriven, the distortion algorithm will soft-clip the signal. Since distortion drive will
make your signal very loud, you may have to reduce the Out Gain as the drive is
increased. [VibChor+Rotor 4 only]
In/Out In or Out Out Gain Off, -79.0 to 24.0 dB
VibChInOut In or Out Dist Drive 0 to 96 dB
Vib/Chor V1 DistWarmth 16 to 25088 Hz
Roto InOut In or Out Cabinet LP 16 to 25088 Hz
Xover 16 to 25088 Hz
Lo Gain Off, -79.0 to 24.0 dB Hi Gain Off, -79.0 to 24.0 dB
Lo Rate -10.00 to 10.00 Hz Hi Rate -10.00 to 10.00 Hz
Lo Size 0 to 250 mm Hi Size 0 to 250 mm
Lo Trem 0 to 100% Hi Trem 0 to 100%
Lo Beam W 45.0 to 360.0 deg Hi Beam W 45.0 to 360.0 deg
LoMicA Pos -180.0 to 180.0 deg LoMicB Pos -180.0 to 180.0 deg
LoMicA Lvl 0 to 100% LoMicB Lvl 0 to 100%
LoMicA Pan -100 to 100% LoMicB Pan -100 to 100%
HiMicA Pos -180.0 to 180.0 deg HiMicB Pos -180.0 to 180.0 deg
HiMicA Lvl 0 to 100% HiMicB Lvl 0 to 100%
HiMicA Pan -100 to 100% HiMicB Pan -100 to 100%
LoResonate 0 to 100% HiResonate 0 to 100%
Lo Res Dly 10 to 2550 samp Hi Res Dly 10 to 2550 samp
LoResXcurs 0 to 510 samp HiResXcurs 0 to 510 samp
ResH/LPhase 0.0 to 360.0 deg

FXAlg #733: VibChor+Rotor 2 ¥ FXAlg #734: VibChor+Rotor 4
Algorithm Reference-109
DistWarmth A lowpass Þlter in the distortion control path. This Þlter may be used to reduce some of
the harshness of some distortion settings without reducing the bandwidth of the signal.
[VibChor+Rotor 4 only]
Cabinet LP A lowpass Þlter to simulate the band-limiting of a speaker cabinet. The Þlter controls the
upper frequency limit of the output.
Xover The frequency at which high and low frequency bands are split and sent to separate
rotating drivers.
Lo Gain The gain or amplitude of the signal passing through the rotating woofer (low-frequency
driver.
Lo Rate The rotation rate of the rotating woofer (low-frequency driver). The woofer can rotate
clockwise or counter-clockwise. The direction of rotation depends on the sign of the rate
parameter. Assuming microphone angles are set toward the front (between -90°and 90°)
and microphones at positive angles are panned to the right (positive pan values), then
positive rates correspond to clockwise rotation when viewed from the top.
Lo Size The effective size (radius of rotation) of the rotating woofer in millimeters. Affects the
amount of Doppler shift or vibrato of the low frequency signal.
Lo Trem Controls the depth of tremolo of the low frequency signal. Expressed as a percentage of
full scale tremolo.
Lo Beam W The rotating speaker effect attempts to model a rotating woofer for the low frequency
driver. The acoustic radiation pattern of a woofer tends to range from omnidirectional
(radiates in directions in equal amounts) to a wide beam. You may adjust the beam
width from 45°to 360°. If you imagine looking down on the rotating speaker, the beam
angle is the angle between the -6 dB levels of the beam. At 360°, the woofer is
omnidirectional.
Hi Gain The gain or amplitude of the signal passing through the rotating tweeter (high-
frequency driver.
Hi Rate The rotation rate of the rotating tweeter (high-frequency driver). The tweeter can rotate
clockwise or counter-clockwise. The direction of rotation depends on the sign of the rate
parameter. Assuming microphone angles are set toward the front (between -90°and 90°)
and microphones at positive angles are panned to the right (positive pan values), then
positive rates correspond to clockwise rotation when viewed from the top.
Hi Size The effective size (radius of rotation) of the rotating tweeter in millimeters. Affects the
amount of Doppler shift or vibrato of the high frequency signal.
Hi Trem Controls the depth of tremolo of the high frequency signal. Expressed as a percentage of
full scale tremolo.
Hi Beam W The rotating speaker effect attempts to model a rotating horn for the high frequency
driver. The acoustic radiation pattern of a horn tends to be a narrow beam. You may
adjust the beam width from 45°to 360°. If you imagine looking down on the rotating
speaker, the beam angle is the angle between the -6 dB levels of the beam. At 360°, the
horn is omnidirectional (radiates in all directions equally).
Mic Pos The angle of the virtual microphones in degrees from the ÒfrontÓ of the rotating speaker.
This parameter is not well suited to modulation because adjustments to it will result in
large sample skips (audible as clicks when signal is passing through the effect). There are
four of these parameters to include 2 pairs (A and B) for high and low frequency drivers.
Mic Lvl The level of the virtual microphone signal being sent to the output. There are four of
these parameters to include 2 pairs (A and B) for high and low frequency drivers.
Mic Pan Left-right panning of the virtual microphone signals. A setting of -100% is panned fully
left, and 100% is panned fully right. There are four of these parameters to include two
pairs (A and B) for high and low frequency drivers.

FXAlg #733: VibChor+Rotor 2 ¥ FXAlg #734: VibChor+Rotor 4
Algorithm Reference-110
LoResonate A simulation of cabinet resonant modes express as a percentage. For realism, you should
use very low settings. This is for the low frequency signal path.
Lo Res Dly The number of samples of delay in the resonator circuit in addition to the rotation
excursion delay. This is for the low frequency signal path.
LoResXcurs The number of samples of delay to sweep through the resonator at the rotation rate of
the rotating speaker. This is for the low frequency signal path.
HiResonate A simulation of cabinet resonant modes expressed as a percentage. For realism, you
should use very low settings. This is for the high frequency signal path.
Hi Res Dly The number of samples of delay in the resonator circuit in addition to the rotation
excursion delay. This is for the high frequency signal path.
HiResXcurs The number of samples of delay to sweep through the resonator at the rotation rate of
the rotating speaker. This is for the high frequency signal path.
ResH/LPhs This parameter sets the relative phases of the high and low resonators. The angle value
in degrees is somewhat arbitrary and you can expect the effect of this parameter to be
rather subtle.

FXAlg #734: Distort + Rotary
Algorithm Reference-111
FXAlg #734: Distort + Rotary
Small distortion followed by rotary speaker effect
Allocation Units: 2
Distort + Rotary models an amplifier distortion followed by a rotating speaker. The rotating speaker has separately
controllable tweeter and woofer drivers. The algorithm has three main sections. First, the input stereo signal is
summed to mono and may be distorted by a tube amplifier simulation. The signal is then passed into the rotator
section where it is split into high and low frequency bands and the two bands are run through separate rotators.
The two bands are recombined and measured at two positions, spaced by a controllable relative angle (microphone
simulation) to obtain a stereo signal again. Finally the signal is passed through a speaker cabinet simulation.
Block diagram of Distort + Rotary
The first part of Distort + Rotary is a distortion algorithm. See the section of this book on FXAlg #723 for details.
Next the signal passes through a rotating speaker routine. See the section of this book on FXAlg #733 for details.
Parameters:
PAGE 1
PAGE 2
PAGE 3
In/Out In or Out Out Gain Off, -79.0 to 24.0 dB
Cabinet HP 16 to 25088 Hz Dist Drive 0 to 96 dB
Cabinet LP 16 to 25088 Hz DistWarmth 16 to 25088 Hz
Xover 16 to 25088 Hz Mic Angle 0.0 to 360.0 deg
Lo Gain Off, -79.0 to 24.0 dB Hi Gain Off, -79.0 to 24.0 dB
Lo Rate -10.00 to 10.00 Hz Hi Rate -10.00 to 10.00 Hz
Lo Size 0 to 250 mm Hi Size 0 to 250 mm
Lo Trem 0 to 100% Hi Trem 0 to 100%
ResH/LPhs 0.0 to 360.0 deg
LoResonate 0 to 100% HiResonate 0 to 100%
Lo Res Dly 10 to 2550 samp Hi Res Dly 10 to 2550 samp
LoResXcurs 0 to 510 samp HiResXcurs 0 to 510 samp
Distortion
Rotator
Rotator
L Input
R Input
L Output
R Output
Out GainCabinet

FXAlg #734: Distort + Rotary
Algorithm Reference-112
In/Out When set to ÒInÓ, the algorithm is active; when set to ÒOffÓ the algorithm is bypassed.
Out Gain The overall gain or amplitude at the output of the effect. For distortion, it is often
necessary to turn the output gain down as the distortion drive is turned up.
Dist Drive Applies a boost to the input signal to overdrive the distortion algorithm. When
overdriven, the distortion algorithm will soft-clip the signal. Since distortion drive will
make your signal very loud, you may have to reduce the Out Gain as the drive is
increased.
DistWarmth A lowpass Þlter in the distortion control path. This Þlter may be used to reduce some of
the harshness of some distortion settings without reducing the bandwidth of the signal.
Cabinet HP A hipass Þlter to simulate the band-limiting of a speaker cabinet. The Þlter controls the
lower frequency limit of the output.
Cabinet LP A lowpass Þlter to simulate the band-limiting of a speaker cabinet. The Þlter controls the
upper frequency limit of the output.
Xover The frequency at which high and low frequency bands are split and sent to separate
rotating drivers.
For details on the rest of the parameters see the previous section (FXAlg #733) of this book.

FXAlg #735/6: KB3 FX
Algorithm Reference-113
FXAlg #735/6: KB3 FX
Vibrato/chorus into distortion into rotating speaker into cabinet
Allocation Units: 7 for full working effect (4 for KB3 FXBus, 3 for KB3 AuxFX)
The KB3 FXBus and KB3 AuxFX algorithms contain multiple effects designed for the Hammond B3 emulation (KB3
mode). For correct operation, both effects must be running at the same time, with the output of KB3 FXBus feeding
the input of KB3 AuxFX. The two algorithms work as one algorithm which use all the available KDFX resources.
While the input to KB3 FXBus is stereo (which gets summed to mono) and the output from KB3 AuxFX is stereo,
the signals between the two algorithms are the low frequency (left) and high frequency (right) signal bands used to
drive the lower and upper rotary speakers. It is possible to run these two algorithms as independent effects, but it
is recommended.
These effects are the Hammond vibrato/chorus, amplifier distortion, and rotating speaker (Leslie) emulations.
Each of these effects may be turned off or bypassed, or the entire algorithm may be bypassed. To bypass the rotary,
the switches in both KB3 FXBus and KB3 AuxFX must be set to ÒOutÓ.
Block diagram of KB3 FXBus
Block diagram of KB3 AuxFX
The first effect in the chain is the Hammond vibrato/chorus algorithm. The vibrato/chorus has six settings which
are the same as those used in the Hammond B3: three vibrato (V1, V2, V3) and three chorus (C1, C2, C3) settings.
The vibrato chorus has been carefully modeled after the electro-mechanical vibrato/chorus in the B3.
An amplifier distortion algorithm follows the vibrato/chorus. For details, see the section in this book on FXAlg
#723.
The distorted signal is next passed to a cabinet emulation filter and a pair of crossover filters for band splitting. The
measurements of a real Leslie¨ speaker was used in the design of these filters. Default parameter values reflect
these measurements, but you may alter them if you like. The Lo HP parameter controls a hipass filter which defines
the lowest frequency to pass through the speaker. Likewise the Hi LP parameter is a lowpass filter controlling the
Vibrato/
Chorus Distortion Cabinet Filter
L Input
R Input
L Output
R Output
Hi Gain
Lo Gain
Rotator
Rotator
Pan
Pan
Pan
Pan
L Input
R Input
L Output
R Output
Mic Levels Out Gain