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Module A-192-2 contains two
independent CV/Gate-to-Midi/USB interfaces. For each of the two sub-units these
inputs are available:
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Gate Input (min. +5V)
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CVN Input (defines the Midi note
number), 1V/octave standard, range 0...+10V (i.e. 10 octaves)
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CVV Input (defines the velocity
value assigned to the Midi note message), can be used alternatively for Midi
volume (CC#7), range 0...+5V
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CVC Input (free assignable to
any Midi control change number), range 0...+5V
For both sub-units a common CV
Transpose input is available (1V/octave, range 0...+10V). The voltage applied to
this input is added internally to CVN before the Midi note number is generated.
It can be used e.g. to transpose two sequences simultaneously by one voltage.
How it works:
Whenever the rising edge of the Gate input is recognized a Midi note on
message is generated. The note number corresponds to the sum of the voltages
applied to the CVN input and the common CV Transpose Input that is present at
the rising edge of the gate signal. In Velocity mode
the voltage applied to the CVV input is used to define the velocity data of the
Midi note on message (in Volume mode a fixed velocity value 100 is
used). As soon as the falling edge of the Gate input is recognized the
corresponding Midi note off message is generated (i.e. with the same note
number as the preceding Midi note on message). The voltages at the CVN
and CV Transpose inputs during the falling edge of the Gate do not have an
effect on the note number of the note off message ! In any case the note
number of the preceding note on message is taken. Otherwise hanging Midi
notes would occur !
The CVV socket is normalled to +5V, i.e. as soon as the jack plug is removed
from the CVV socket the max. velocity or volume data (127) are generated.
Otherwise no audible sound would be generated (because of velocity or volume =
0).
The CVC voltage is permanently converted into the corresponding Midi control
change message, as well as the CVV voltage provided that the Volume mode
is chosen. The difference between Velocity mode and Volume mode is
the function of the voltage applied to CVV. In Velocity mode the voltage
CVV is used to define the velocity value of the corresponding Midi note on
message and is measured only during the rising edge of the Gate input. In Volume
mode the CVV voltage is permanently converted into Midi Volume messages
(Midi control change #7). The CVC socket is normalled to 0V, i.e. as soon as the
jack plug is removed from the CVC socket Midi control change data 0 are
generated.
Adjustment of the Conversion
Parameters
The conversion parameters for each unit are adjusted by means of the Learn
button in combination with incoming Midi data (e.g. generated by a Midi keyboard
connected to Midi In of the A-192-2). The learn mode is initiated by operating
the Learn button for about one second. While the unit is in learn mode
the corresponding LED is flashing. The next incoming Midi note on message
is used to set the Midi channel and note reference for the sub-unit in question.
The voltage currently applied to the CVN socket is assigned to the Midi note
number of the note message.
Example 1: 0V are applied to
CVN (or the CVN socket is left open) and a Midi note message with note number 36
on Midi channel 1 is sent while the upper sub-unit of the module is in learn
mode: then a CVN voltage of 0V corresponds to Midi note number 36 for the upper
sub-unit and the data are sent on Midi channel 1.
Example 2: +2.5V are applied to CVN and a Midi note message with note
number 47 on Midi channel 11 is sent while the lower sub-unit of the module is
in learn mode: then a CVN voltage of +2.5V corresponds to Midi note number 47
for the lower sub-unit and the data are sent on Midi channel 11.
When a Midi control change message is
received while the unit is in learn mode the control change number of the Midi
message is taken for CVC (except CC#0 and CC#32 as these are reserved for Midi
program bank change). Program change messages are used in learn mode to select the
Volume mode (program change #0) or Velocity mode (program
change #1). Pay attention that the Midi channel of the incomung control change
or program change messages has to correspond to the Midi channel that is
assigned to the A-192-2 sub-unit in question.
In addition one can switch between the two modes without the need of
a program change transmitter: for this one has to operate the learn button in
question for several seconds. Then the LED starts to flash faster than in the learn mode and the other
function for CVV (volume or velocity) is selected. But with this procedure one has no
optical feedback which mode (volume or velocity) is selected. One simply is able
to toggle between the two
modes. But one can find out very simply which mode is selected because the
module generates continuous Midi volume data only in the Volume mode.
When a variable voltage applied to the CVV socket generates Midi volume data (without a
Gate signal) the Volume mode is selected. Otherwise the Velocity
mode is active.
The data generated by the module are
transmitted simultaneously to Midi Out and USB. Two or more A-192-2 modules can be
daisy-chained via Midi Out - Midi In. Incoming Midi data is merged to the Midi
output - provided that the incoming data volume is not too high (because of the
limited Midi Input buffer of the module). A Midi keyboard
or a second A-192-2 are no problem but please do not try to merge a fully loaded
16 channel sequencer track.
The two LEDs also display the activity of
the sub-units (i.e. if Midi data are generated by the unit in question).
Factory settings:
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Midi reference note for CVN =
0V: 36 (C)
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Velocity mode (CVV generates
velocity data)
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Midi control change number
assigned to CVC: #1 (modulation)
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Sub-unit 1: Midi channel 1
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Sub-unit 2: Midi channel 2
The factory setting can be restored
by operating the learn button of the corresponding sub-unit during power on
(i.e. the button has to be held down while the A-100 system is turned ON).
Typical applications:
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Conversion of analog sequences
into Midi/USB data (e.g. A-155)
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Generating random Midi sequences
(e.g. with CVN coming from A-118 or A-149-1,
Gate e.g. from an LFO)
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Generating Midi control change
data from analog voltages
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If bipolar or negative voltages
have to be converted an offset generator is recommended (e.g. A-183-2).
There is also an internal jumper available on the A-192-2 board that adds
about +5V to the incoming control voltages CVN, CVV and CVC as soon as the
jumper is installed.
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