Antares Filter user manual

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5FILTERS #1 AND #2 IN SERIES WITH THEIR
OUTPUT ROUTED TO #3 AND #4 IN
PARALLEL In this configuration, audio is
routed to the input of Filter #1 and after
being processed is sent to the input of Filter
#2. The output of Filter #2 is then sent to the
inputs of both Filter #3 and Filter #4 where it
is processed in parallel with the outputs of #3
and #4 mixed together for the final output.
6ALL FOUR FILTERS IN SERIES In this configura-
tion, the audio is first routed to Filter #1 and
its output then passed through each filter in
turn for further processing. It should be noted
that in this configuration it is extremely easy
to end up with no audio at the output. See
the following notes for details.
IMPORTANT NOTE: Unlike routing configuration #1, which is pretty
much foolproof, when you route filters in series, you need to pay close
attention to each filter’s configuration and cutoff frequency to avoid
ending up with a patch that makes no sound. Since each filter subtracts
some portion of a signal’s harmonic content and then passes it on to
the next filter for more to be subtracted, it’s all too easy in series
routings to end up with nothing left at the final output.
When this happens, solo each filter in the series in order from the first
to last to find out where the audio disappears and then modify the
offending filters’ settings as necessary.
As an example, suppose you’re processing a wideband signal through
Filters #1 and #2. You’ve set Filter #1 for lowpass at 250Hz and Filter #2
for highpass at 5kHz, so the filter display will look like this:
It’s obvious that when the two filters are routed in parallel, the output
will be your original audio with the range between 250Hz and 5kHz
seriously filtered. However, switch to routing #2 and you will hear no
output at all. The reason is that Filter #1 starts out by removing the
portion of your audio above 250Hz and then passes the remaining 
						

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portion on to Filter #2 which removes audio under 5kHz. Since the
entire signal from Filter #1 is under 5kHz, there’s nothing left to send
to the output.
ANOTHER NOTE: The one place where series routing is not only useful,
but pretty much required is when you’re dealing with multiple notch
filters. As an example, choose routing #6 and set all four filters to
notch at different frequencies. Link #2, #3 and #4 to #1 and sweep #1’s
frequency to hear the effect. Now switch to routing #1 and try the
same thing. There will be very little effect because each of the parallel
filters is “filling in” the other 3 filters’ notches.
YET ANOTHER NOTE: When using parallel routings, and particularly
routing #1, keep in mind that the final output is the sum of all of the
active filters’ outputs. If you have three or four filters emphasizin\
g the
same frequency ranges or with high Qs, you can generate levels that
can cause clipping and distortion. To prevent this, adjust the individual
filters’ Gain controls to eliminate the clipping.
Function Generators
Filter’s four Function Generators provide a huge variety of dynamic control
signals that can be used in combination with the Modulation Matrix to
affect pretty much any key Filter parameter.
Each of the four Function Generators provides both an Envelope Generator
and a Low Frequency Oscillator (LFO), thereby offering a simultaneous total
of 4 Envelope Generators and 4 LFOs. Even though each Function Genera-
tor can only display the interface of one or the other at a time, both
functions are available simultaneously in the Modulation Matrix, i.e.,
Function Generator 1 provides both LFO 1 and Env 1, Function Generator 2\
provides both LFO 2 and Env 2, etc.
Use the LFO/ENV rocker switch in the lower right hand corner of each
Function Generator to select which function to display.
LFOs
Each of Filter’s four identical LFOs (Low Frequency Oscillators), provides 10
different shapes — including three different random shapes — and can be
set to an independent rate or synced to Filter’s Master Tempo. 
						

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NOTE: When using an LFO to produce a desired effect on a particular
parameter, it is important to recognize that the LFO provides a bipolar
control signal, i.e., the signal is centered around the value of 0 (the
value at which it has no effect on the controlled parameter) and
(except for the random shapes) moves symmetrically both above and
below 0.
What this means in practice is that an LFO will cause the parameter it is
controlling to alternately increase and decrease relative to its initial
value. If you are going to control something with an LFO, the
parameter’s initial value should be set with this behavior in mind.
SYNC TO MASTER
Click on the Sync To Master button to toggle its state.
When the button is lit, the LFO is locked to Filter’s Master Tempo and its
rate is set in beats or fractional beats relative to that tempo. When it is not
lit, the LFO’s rate can be set directly in Hz or BPM.
NOTE: When an LFO is Synced To Master, it is truly locked to the master
tempo, its rate can not be affected by modulation.
RATE STYLE
When an LFO is not Synced To Master, click one of the two Rate Style
buttons to display the LFO’s rate in either BPM or Hz. (This function also
serves as a handy Hz to BPM calculator.)
When an LFO is Synced To Master, this control is inactive and the buttons
are grayed out.
RATE/BEATS
This control is used to set the LFO’s frequency. Its label and function depend
on the state of the Sync To Master button.
NOTE: Whether you are setting the frequency as an absolute rate or in
relative beats, this control defines the time it takes the LFO to com-
plete one cycle of the selected shape (keep in mind that each LFO’s
Graphic Shape Display shows three complete cycles). So for shapes 1-7,
the frequency is the time it takes for the LFO to start at zero, move
through its selected shape and then return to zero ready to start the
cycle again. In the case of the three random shapes, the frequency
defines the amount of time that each random value is held. The actual
shape of the LFO in these cases depends on which type of random
shape is selected and the actual sequence of values (see the LFO shape
descriptions below). 
						

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BEATS
When the LFO is synced to the master tempo (the Sync To Master button is
lit), this parameter is labeled Beats and is set in beats or fractional\
 beats
relative to the Master Tempo.
Use the Beats knob to select the desired beat division.
The data display will indicate the selected beat as follows:• For two or more beats, the number of beats (i.e., 2, 3, 4, ...16)
• For beat divisions, a graphic representation of selected beat division
Y ou may also click in the data display to display a popup menu of the
available values. The choices are:
32nd note triplet (1/12 beat)
32nd note (1/8 beat)
dotted 32nd note (3/16 beat)
16th note triplet (1/6 beat)
16th note (1/4 beat)
dotted 16th note (3/8 beat)
8th note triplet (1/3 beat)
8th note (1/2 beat)
dotted 8th note (3/4 beat)
quarter note triplet (2/3 beat)
quarter note (1 beat)
dotted quarter note (1 1/2 beats)
2 beats
3 beats
4 beats
…
16 beats
Option (Mac)/Alt (PC) clicking the knob will reset the value to 1 be\
at .
RATE
When the LFO is not synced to the master tempo (the Sync To Master
button is not lit), this parameter is labeled Rate and is set in Hz or \
BPM
(depending on the Rate Style setting).
Use the Rate knob to set the LFO’s frequency over a range of 0.10 Hz to 20
Hz or 6 BPM to 1200 BPM.
For ease in setting precise rates, press the Shift key on your keyboard \
while
turning the knob to increase the resolution.
The numeric display will indicate the selected rate in Hz or BPM.
Y ou may also click in the numeric display and type in the desired rate.
Option (Mac)/Alt (PC) clicking the knob will reset the value to 1 Hz\
 or
60 BPM. 
						

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TRIANGLE: Similar to the Sine shape, but with a
sharp (and potentially audible) change of direc-
tion at the maximum and minimum points. NOTE: Keep in mind that in addition to simply defining the LFO
frequency’s unit of measure, a further difference is that when you set
LFO rate in Hz or BPM you are setting an absolute frequency, while
when you set it in beats you are setting a relative frequency.
For example, if you set an LFO rate of 12 BPM or .20 Hz (they are
equivalent), the LFO will complete a single cycle in exactly 5 seconds,
regardless of any changes to the tempo of your track. On the other
hand, if you are Synced To Master and have a track at a tempo of 120
BPM and you set the rate to 10 beats, the LFO will also complete a
single cycle in exactly 5 seconds (the length of 10 beats at 120 BPM).
However, if later in the track the tempo changes to 150 BPM, the LFO’s
rate will change to one cycle every 4 seconds (the length of 10 beats at
150 BPM).
In short, if the absolute length of the LFO pattern is of primary impor-
tance, set the rate in Hz or BPM. If, however, the LFO is a component of
a tempo-dependent rhythmic pattern, Sync it to the Master Tempo so
that it will remain in proper sync with any tempo changes.
SHAPE
To select one of the LFO’s 10 shapes, click on the appropriate Shape button
or click on the shape name to display a popup menu of the available
choices. In either case, a graphic representation of 3 cycles of the chosen
shape will appear on the Shape display.
The available shapes are:
SINE: Starting at zero, the control signal moves
smoothly to the maximum, to the minimum, and
then back to zero. Great for smoothly sweeping
filter frequencies.
RAMP UP: Starts by instantaneously jumping to
the minimum value and then spending the entire
cycle moving up to the maximum value.
RAMP DOWN: The inverse of the Ramp up. Starts
by instantaneously jumping to the maximum
value and then spending the entire cycle moving
down to the minimum value. 
						

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SQUARE: Jumps to maximum where it spends 50%
of the cycle and then jumps to minimum for the
remaining 50% of the cycle. Used to rhythmically
switch a parameter between two specific values.
SHORT PULSE: Like the Square shape, but spends
only 25% of the cycle at maximum and 75% at
minimum.
LONG PULSE: The inverse of the Short Pulse.
Spends 75% of the cycle at maximum and 25% at
minimum.
THE RANDOM SHAPES: For the three Random shapes, a random value is
generated for each cycle period. The shapes differ in how they transition
from value to value:
RANDOM HOLD: For this shape, the LFO remains
at the random value for the entire cycle period
and then instantaneously changes to the next
value. This is the classic sample-and-hold effect so
beloved on early analog synthesizers.
RANDOM SLEW: With Random Slew, the LFO
glides smoothly from value to value, taking
exactly one cycle to move from the last value to
the next one. Useful in moderation for adding
some random “human error” to an otherwise too
perfect parameter.
RANDOM RAMP: This unique shape starts each
cycle by instantaneously jumping up to the new
random value and then spending the rest of the
cycle ramping down to minimum.
TIP: Try routing the Random Ramp shape to a filter’s frequency and
gain. Sync the rate to the master tempo and select a beat of an 8th
or 16th note. By adjusting the filter’s initial frequency and gain and
the LFO’s modulation depths, you can create a variety of percussive
rhythms with intricate, randomly generated harmonic accents. Fun
stuff. 
						

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ANOTHER TIP: A quick way to familiarize yourself with the effects of
the various shapes is to filter a rich pad-type sound with a bandpass
filter with Q set to 50%. Assign an LFO to control the filter’s frequency
(see the Modulation Matrix section for details). Set the LFO’s rate to 27
BPM (or so) and listen to the effects of shapes 1–7. Then boost the rate
to 299 BPM and try each of the three random shapes. All should
become clear.
FUNCTION DISPLAY SELECTOR
Click on the LFO/ENV rocker switch to select which of the Function
Generator’s functions to display. Remember that both functions (LFO and
Envelope) are active simultaneously, regardless of which one’s controls are
currently displayed.
ENVELOPE GENERATORS
Each of Filter’s four identical Envelope Generators provide a flexible way to
create event-based control signals for controlling various Filter parameters.
Each Envelope offers multiple triggering options and parameters that can
be programmed in absolute time or synced to Filter’s Rhythm Generators.
NOTE: When using an Envelope to produce a desired effect on a
particular parameter, it is important to recognize that the Envelope,
unlike an LFO, provides only a positive-going control signal, i.e., the
signal starts at the value of 0 (the value at which it has no effect on the
controlled parameter) and thereafter produces only positive values.
What this means in practice is that an Envelope will always* cause the
parameter it is controlling to increase relative to its initial value. If you
are going to control something with an Envelope, the parameter’s
initial value should be set with this behavior in mind.
* Well, not always always. If you set a negative modulation amount
in the Modulation Matrix (see the Mod Matrix section below for
details), the shape of the envelope will be inverted, causing the
parameter it is controlling to decrease relative to its initial value. But
we’re getting ahead of ourselves. 
						

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ENVELOPE OVERVIEW
An Envelope Generator is essentially a control signal that follows a preset
series of actions at rates and for times that you program. For Filter’s
Envelope Generators, those actions are:
1TRIGGER A trigger is an external signal that tells the Envelope Genera-
tor to begin its actions. In Filter, that trigger can come from one of the
two Rhythm Generators or from a MIDI Note On command.
2DELAY (optional) You can set a delay time between when the Trigger is
received and when the Attack phase begins.
3ATTACK in the Attack phase, the Envelope’s signal rises from zero to
the maximum value at the programmed Attack rate.
4DECAY During the Decay phase, the signal falls from the maximum
level to the Sustain level at the programmed Decay rate.
5SUSTAIN LEVEL This is the level that is maintained during the Hold
time.
6HOLD TIME This is the amount of time that the Envelope remains at
the Sustain level. Depending on the Envelope’s Trigger Source, the Hold
Time is set by the Hold control or by the MIDI Gate time.
7RELEASE During the Release phase, the signal falls from the Sustain
level to zero at the programmed Release rate.
IMPORTANT NOTE: If a new trigger is received by the Envelope Genera-
tor before it has finished all of the phases described above, it will
immediately reset to step #2 and start the process over at that point.
TIME BASE
Click one of the two Time Base buttons to select the units for the
Envelope’s time and rate-based parameters. Choosing “ms” (milliseconds)
will allow you to program the parameters in absolute time. Choosing “RG”
(Rhythm Generators) will allow you to program the parameters as a
percentage of the Rhythm Generator step time (see the Rhythm Generator
section below for details on setting the RG step time).
NOTE: When you choose RG, keep in mind that you are setting the rate
parameters as a percentage of one RG step. If you have programmed
an RG to supply a trigger on every step and you want to have the
envelope complete its entire cycle with each trigger, make sure that the
sum of all the rate parameters does not exceed 100%. Likewise, if you
have programmed an RG to supply a trigger on every other step and
you want to have the envelope complete its entire cycle with each
trigger, make sure that the sum of all the rate parameters does not
exceed 200%. Etc. 
						

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ANOTHER NOTE: Like the Delay time and LFO rate described above,
when you set Envelope parameters in milliseconds, you are setting an
absolute time or rate, while when you set them as a percentage of the
RG step time, you are setting a relative time or rate.
This is of particular importance when you are triggering an Envelope
with a Rhythm Generator. In that case, you will often want to set the
parameters in terms of the RG tempo so that if you later need to
change the tempo, the Envelope will rescale itself to remain in proper
proportion to the rhythm pattern.
In short, if the absolute length of the Envelope is of primary impor-
tance, set the parameters in milliseconds. If, however, the Envelope is a
component of a tempo-dependent rhythmic pattern, set it in terms of
the RG step time so that it will remain in proper sync with any RG
tempo changes.
DELAY
This control is used to set the delay time between the arrival of a trigger
and the onset of the Attack phase. The numeric display will indicate the
time in milliseconds or as a percentage of the Rhythm Generator step time.
You may also click in the numeric display and type in the desired value.
Option (Mac)/Alt (PC) clicking the knob will reset the value to 0 ms or 0%.
NOTE: You must be careful when setting the Delay to ensure that the
delay time is not longer than the time between triggers. If a new
trigger arrives before the entire delay time has passed, the envelope
will reset to the start of the delay time and the Attack phase will never
be reached, giving the impression hat the Envelope is somehow
“broken”or otherwise nonfunctional.
ATTACK
The Attack rate is set graphically on the Graphical Envelope Display by
moving the cursor over the Attack area of the display until the cursor turns
into a double ended horizontal arrow. Click and hold the mouse button
and move left or right to set the desired rate. Then you will see a graphical
representation of the Envelope’s Attack contour and the numeric display
will indicate the time in milliseconds or as a percentage of the Rhythm
Generator step time.
Option (Mac)/Alt (PC) clicking while the cursor is the double ended arrow
will reset the value to 0 ms or 0%.
You may also click in the numeric display and type in the desired value. 
						

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DECAY RATE AND SUSTAIN LEVEL
The Decay Rate and Sustain Level can be set simultaneously on the Graphi-
cal Envelope Display by moving the cursor over the Decay or Sustain area of
the display until the cursor turns into a four-pointed arrow. Click and hold
the mouse button and move left or right to set the desired Decay Rate and
up or down to set the desired Sustain Level. You will see a graphical
representation of the Envelope’s Decay and Sustain contour and the
numeric displays will indicate the selected values.
Option (Mac)/Alt (PC) clicking while the cursor is the four-pointed arrow
will reset the Decay Rate to 50 ms or 12% and the Sustain Level to 70%.
You may also click in the numeric displays and type in the desired values.
HOLD TIME
This control is used to set the time that the Envelope will remain at the
Sustain Level. The numeric display will indicate the time in milliseconds or
as a percentage of the Rhythm Generator step time. For ease in setting
precise times, press the Shift key on your keyboard while turning the knob
to adjust the time by 1ms.
You may also click in the numeric display and type in the desired value.
Option (Mac)/Alt (PC) clicking the knob will reset the value to 160 ms or
19%.
NOTE: This control is inactive if the Envelope’s Trigger Selector is set to
MG (MIDI Gate).
RELEASE
The Release time is set on the Graphical Envelope Display by moving the
cursor over the Release area of the display until the cursor turns into a
double ended horizontal arrow. Click and hold the mouse button and move
left or right to set the desired rate. Then you will see a graphical represen-
tation of the Envelope’s Release contour and the numeric display will
indicate the time in milliseconds or as a percentage of the Rhythm Genera-
tor step time.
You may also click in the numeric display and type in the desired value.
Option (Mac)/Alt (PC) clicking while the cursor is the double ended arrow
will reset the value to 1.0 sec or 40%.
TRIGGER SELECTOR
Click one of the four Trigger Selector buttons to choose the source of the
Envelope’s trigger. The choices are:
•RG1 (Rhythm Generator 1) The envelope will be triggered whenever
Rhythm Generator 1 is running and encounters an active cell. (See the
Rhythm Generator section below for details.)