Pittsburgh Modular Safari Series 1 User manual

Inspired by the random source on the Buchla
Music Easel, the Gibbon is a digitally controlled
complex random source generating a pair of
both gate and CV signals. The random
generator functions similar to an analog shift
register. When the clock signal triggers an
update and the next register value is loaded,
there is a chance it will change. Think of it
like a sequencer. The random generator cycles
through the steps of the sequence and each
time the sequencer jumps to the next step, there
is a chance the value stored in that step will be
replaced with a new value. The result is a
random source that feels both random and
evolutionary, with an ever evolving pattern
cycle. Add to that adjustable pattern length,
adjustable stored voltage difference range, the
chance for triggers on clock subdivisions, and
the output becomes even more chaotic.
Size 4hp
Depth 24mm
Power +12v 50mA / -12v 10mA
pgh
Apparently Gibbons are not very
good at keeping track of large
sequences of numbers.
©2020 Pittsburgh Modular Synthesizers
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Knobs and Jacks
Clock IO Jack External clock input, internal clock output, or randomized internal clock
output depending on the clock mode selected.
Mod Input Jack External CV input used to mod the pattern variation.
Trigger LEDs Represents the trigger state of the clock (LED1), out a (LED2), and out b
(LED3).
Stages Control Assigns the number of shift register stages from 1-24.
Spread Control Selects the general range of change when a shift register stages value
changes. Smaller range to the left and a larger range to the right. Spread Control also
sets the chance a stage value will change. Less chance to the left and more chance
to the right.
Variation Control Determines the complexity of the output. Less variation will trigger
fewer gates and reduce the chances of gates triggering on sub divisions of the clock.
More variation increases the chances that a gate will trigger on the clock and sub
divisions of the clock.
Out A Jack CV or gate output jack depending on selected output mode.
Out B Jack CV or gate output jack depending on selected output mode.
Despite what you may think, the point of this manual is to
explain how the Gibbon works, not to make it more
confusing.
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Clock Button
Modify clock related settings depending on selected clock mode. Pressing the Clock
Button in external clock mode cycles through clock divisions 1-8. When in internal clock
mode, the Clock Button functions as a tap tempo clock source.
Select Clock Source
Cycle through the 3 available clock modes. Press and hold the Mode Button then
press the Clock Button to cycle through clock modes.
External Clock Mode LED1 lit. Clock IO Jack functions as clock input jack. Clock Button
cycles through clock divisions 1-8.
÷ : LEDS
1:XXX
2 : 0 X X
3 : X 0 X
4:XX0
5:00X
6 : X 0 0
7 : 0 X 0
8:000
Internal Clock Mode LED2 lit. Clock IO Jack functions as clock output jack. Tap tempo
using Clock Button.
Internal Gate Mode LED3 lit. Clock IO Jack does not output a steady clock. Instead
Clock IO Jack functions as random gate output. Tap tempo using Clock Button.
Free Running Mode
Disconnects the Gibbon from the clock source to create unclocked, chaotic updates.
Press and hold Clock Button for 3 seconds to enable or disable free running mode.
Free Running Mode Off LED1 and LED2 lit. The selected clock source has full control.
Free Running Mode On LED2 and LED3 lit. Internal clock mode has no control over
timing but the Clock IO Jack does inuence timing when in external clock mode.
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Mode Button
Selects between CV and Gate signal outputs for Out A Jack and Out B Jack.
Select Output Mode Cycle through the 3 available output modes. Press the
Mode button to cycle through output modes.
Mode 1 LED 1 lit. Out A and Out B output CV signals.
Mode 2 LED 2 lit. Out A outputs CV, Out B outputs a gate.
Mode 3 LED 3 lit. Out A and Out B output gates.
Reset Clock Divider In external clock mode, press and hold the Clock Button
then press the Mode button to reset the internal clock divider counter.
Clear Shift Register Values In internal clock mode or internal gate mode,
press and hold the Clock Button then press the Mode button to clear the shift register
CV values.
Clock Trigger Passive Variation Mode
The event that happens when the clock is triggered will use the chance algorithm of
the last event that happened instead of its own chance algorithm. This may or may
not make sense but in practice it means there may be less chance a gate/CV update
will happen when the clock is triggered. That explanation probably did not help.
Anyway… Press and hold Mode Button for 3 seconds to enable or disable clock trigger
passive variation mode.
Clock Trigger Passive Variation Mode Off LED1 and LED2 lit. Variation chance is based
on specic chance algorithm for on clock events.
Clock Trigger Passive Variation Mode On LED2 and LED3 lit. Variation chance is based
on the last used chance algorithm.
v1.1
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clock io mod