applied-acoustics-systems ultra analog Manuel D’Utilisation
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Parameters
4.8
The Keyboard Module
The Keyboard module controls how the synthesizer voices respond
to the events coming from an external MIDI keyboard or from a MIDI
sequencer. The first row of controls (Tuning, Octave, Semi) is used to fix
the pitch of the keyboard, and transpose the overall keyboard by octaves
or semi-tones. The two knobs Stretch and Error on the bottom row, allow
to stretch the octaves and/or add a random error on each note played. The
second line of parameters allows one to select the mode of operation:
unison, polyphonic or monophonic as well as the note priority. The first
two knobs on the third row, Detune and Decay, are used to set the detune amount and the time
delay respectively between each voice of a note when the unison mode is selected.
sequencer. The first row of controls (Tuning, Octave, Semi) is used to fix
the pitch of the keyboard, and transpose the overall keyboard by octaves
or semi-tones. The two knobs Stretch and Error on the bottom row, allow
to stretch the octaves and/or add a random error on each note played. The
second line of parameters allows one to select the mode of operation:
unison, polyphonic or monophonic as well as the note priority. The first
two knobs on the third row, Detune and Decay, are used to set the detune amount and the time
delay respectively between each voice of a note when the unison mode is selected.
4.8.1
Tuning
The pitch of A4 (normally 440 Hz) is adjusted, in Hertz, in the Tuning display. The pitch can be
transposed by −3 to +3 octaves and −12 to +12 semi-tones by using the Octave and Semi drop-
down menus. Once the tuning of the keyboard has been determined trough the use of these three
controls, one can slightly alter it with the Stretch and the Error knobs. The Stretch knob sets the
value of a semi-tone, when in the center position, the semi-tone interval corresponds to that of the
equal-tempered scale, turning the knob to the left will shrink the interval while turning it to the right
will increase it. The main effect of the Stretch control is that when it is not in the center position,
an interval of one octave will not sound perfectly in tune and therefore beating will be heard when
playing perfect octaves. The Error knob adds a random error to each note played, the more the
knob is turned clockwise, the larger is the error. This will make all the notes play slightly out of
tune. Note that the sustain pedal (MIDI controller number 64) is always active on the Keyboard
module.
transposed by −3 to +3 octaves and −12 to +12 semi-tones by using the Octave and Semi drop-
down menus. Once the tuning of the keyboard has been determined trough the use of these three
controls, one can slightly alter it with the Stretch and the Error knobs. The Stretch knob sets the
value of a semi-tone, when in the center position, the semi-tone interval corresponds to that of the
equal-tempered scale, turning the knob to the left will shrink the interval while turning it to the right
will increase it. The main effect of the Stretch control is that when it is not in the center position,
an interval of one octave will not sound perfectly in tune and therefore beating will be heard when
playing perfect octaves. The Error knob adds a random error to each note played, the more the
knob is turned clockwise, the larger is the error. This will make all the notes play slightly out of
tune. Note that the sustain pedal (MIDI controller number 64) is always active on the Keyboard
module.
4.8.2
Mode and Priority
The keyboard can be monophonic, allowing to play only one note at a time or polyphonic, allowing
the play chords. This behavior is adjusted with the Mode drop-down menu. The Priority control,
located on the right of the Mode control, sets the behavior of the keyboard when several notes are
depressed at the same time in monophonic mode or when the maximum number of polyphonic
voices has been reached in polyphonic mode. In monophonic mode, the Priority determines which
of the lower, last or higher note has precedence when several notes are played. In polyphonic mode,
this control determines which of the lowest, highest or oldest note is muted in order to replace it
with the newest note played once the maximum of polyphonic voices has been reached. Note
that since this parameter determines the note priority, the stolen note will be the opposite of what
appears in the control display.
the play chords. This behavior is adjusted with the Mode drop-down menu. The Priority control,
located on the right of the Mode control, sets the behavior of the keyboard when several notes are
depressed at the same time in monophonic mode or when the maximum number of polyphonic
voices has been reached in polyphonic mode. In monophonic mode, the Priority determines which
of the lower, last or higher note has precedence when several notes are played. In polyphonic mode,
this control determines which of the lowest, highest or oldest note is muted in order to replace it
with the newest note played once the maximum of polyphonic voices has been reached. Note
that since this parameter determines the note priority, the stolen note will be the opposite of what
appears in the control display.