WaveWarp 2.0 Component
      
Signal Generators:
Telegraph Noise Control Generator (A)
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Functional Description
Generates a
telegraph (two-state)
control signal with a (pseudo-)random distribution
of change-points. The output is
nominally scaled between 0 and 1 (for use as an "Amplitude" controller).
NOTE: the sample rate at which this component is executed can be arbitrarily set via the
"Sample-rate setting for Signal Generators and
Input ASCII files" button
(or the "Sample-Rate Setting" command under the "Edit" menu) on the toolbar, which is
activated whenever the component is selected on the DrawingBoard.
Equivalently, it can be set via the dialog box which (i) appears
when the component is initially
dragged on to the DrawingBoard or (ii) is activated using the right-mouse-button when
the component is selected on the DrawingBoard.
This procedure allows the component to either (i) enforce
a user-determined sample rate on the downstream component(s), or (ii) to inherit the sample rate from
the downstream component(s). Different signal generators can run at different
sample rates on a DrawingBoard, as long as the rules of connectivity
for multiple sample rates are adhered to (see the
WaveWarp Users' Guide
for more information.)
The characteristics of the noise signal are adjustable via
the Parameter Window, as summarised in the
following table.
| Parameter | Purpose |
|---|
| "Bandwidth" slider |
Adjusts the bandwidth of the output noise signal. New
change-points occur
at pseudo-randomly
generated
intervals corresponding to the selected bandwidth.
Between these change-points, the control signal output will retain its previous value.
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| "Amplitude" slider |
Adjusts the amplitude of the output signal.
Depending on the selected "Unmodulated amplitude range", the control signal output will be scaled either between
-1 and 1, or between 0 and 1.
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| "Enable modulation" checkbox |
If enabled, the
"Unmodulated amplitude range"
selection is automatically disabled, and the "Amplitude" slider becomes
a "Depth" slider. The control signal ouput will be automatically scaled
over the range from 0 to 1.
The "Depth" determines the fraction of this range over which the
noise sequence will be
mapped. Maximum "Depth" (a value of 1) implies that the noise sequence will be
mapped on to the entire range from 0 to 1, thereby maximising the signal variation.
Minimum "Depth" (a value of 0) implies no mapping, thereby minimising
the signal variation (i.e. constant
output). An intermediate value, say 0.2, implies that the ouput of the noise sequence
will be
mapped on to the upper 20% of the output range, and so forth.
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| Plot window |
Displays a representative portion of the output noise sequence,
reflecting the time scaling due to the "Bandwidth" setting, and the
amplitude
scaling due to
the "Amplitude", "Unmodulated amplitude range",
and "Depth" settings.
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Algorithm
Utilizes a pseudo-random number generator using the system clock as
a "seed".
Signal Implementations
| Audio signals | Control signals | Description |
|---|
| n/a | single output | Generates a control signal with an amplitude nominally between 0 and 1 |
Related components:
Example DrawingBoards illustrating usage:
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