User Manual

18
Pitch
The three controls Range
7
, Coarse
8
and Fine
9
set the Oscillator’s fundamental
frequency (or Pitch). The Range button selects traditional “organ-stop” units, where
16’ gives the lowest frequency and 2’ the highest. Each doubling of stop length halves
the frequency and thus transposes the pitch of a note played at the same position on a
keyboard down one octave. When Range is set to 8’, the keyboard will be at concert pitch
with Middle C in the centre. The LEDs confirm the stop length currently selected.
The Coarse and Fine rotary controls adjust the pitch over a range of ±1 octave and
±1 semitone respectively. The OLED display shows the parameter value for Coarse in
semitones (12 semitones = 1 octave) and Fine in cents (100 cents = 1 semitone).
Pitch Modulation
The frequency of each Oscillator may be varied by modulating it with either (or both) LFO
2 or the Mod Env 2 envelope. The two Pitch controls, Mod Env 2 Depth
11
and LFO 2
Depth
12
control the depth – or intensity – of the respective modulation sources.
Note that each Oscillator has a Depth control for modulation by LFO 2. It is also possible
to modulate all three Oscillators simultaneously by LFO 1: this patch is set up in the Mod
Matrix – see page 26. Oscillator pitch can be varied by up to five octaves, but the
LFO 2 depth control is calibrated to give finer resolution at lower parameter values (less
than ±12), as these are generally more useful for musical purposes.
Negative values of LFO 2 Depth “invert” the modulating LFO waveform; the effect of this
will be more obvious with non-sinusoidal LFO waveforms.
Adding LFO Modulation can add a pleasing vibrato when a sine or triangle LFO waveform
is used, and the LFO speed is set neither too high nor too low. A sawtooth or square LFO
waveform will produce rather more dramatic and unusual effects.
Adding envelope modulation can give some interesting effects, with the oscillator pitch
altering over the duration of the note as it is played. With the parameter value set to
maximum (±127), the oscillator pitch will vary over eight octaves. A parameter value of
8 shifts the pitch by one octave at the maximum level of the modulation envelope (e.g., if
sustain is at maximum). Negative values invert the sense of the pitch variation; i.e., the pitch
will fall during the attack phase of the envelope if Mod Env depth has a negative setting.
Shape
Peak lets you modify the “shape” of the selected waveform; this will alter the harmonic
content and thus the timbre of generated sound. The degree of modification – or deviation
from the “classic” waveform type – can be varied both manually and as a modulation. The
modulation sources available using the panel controls are Mod Env 1 and LFO 1; many
other mod sources may be selected using the Modulation Matrix – see page 26.
The Source button
13
assigns the Shape Amount control
14
to one of the sources.
When set to Manual, Shape Amount lets you alter the waveform shape directly; the
parameter range is -63 to +63, where 0 corresponds to an unmodified waveform. The
precise effect of Shape Amount will depend on the waveform in use.
When Sine is selected as the waveform, a non-zero Shape Amount parameter will add
distortion, resulting in the addition of upper harmonics. Similarly, varying Shape Amount
with Triangle or Sawtooth waveforms modifies wave shape and thus the harmonic content.
When Square/Pulse is selected as the waveform, Shape Amount will vary the pulse
width: a value of 0 produces a 1:1 square wave. The timbre of the “edgy” square wave
sound can be modified by varying the pulse width, or duty cycle, of the waveform. Extreme
clockwise and anticlockwise settings produce very narrow positive or negative pulses, with
the sound becoming thinner and more “reedy” as the control is advanced.
When the waveform is set to more, Shape Amount selects the waveform by sweeping
across the five columns in the selected wavetable to produce a “morphing” of two adjacent
columns: the sonic effect of this will vary greatly depending on the active patch and the
wavetable in use. We recommend you experiment altering Shape Amount with different
waveforms to hear the effect.
Shape may also be modulated by either (or both) Mod Env 1 or LFO 1, as selected by
Source
13
. With pulse waveforms, the sonic effect of LFO modulation is very dependent
on the LFO waveform and speed used, while using envelope modulation can produce some
good tonal effects, with the harmonic content of the note changing over its duration.
The Oscillator Menu
The following additional Oscillator parameters are available in the Osc menu. Each of the
three oscillators has two menu pages; the parameters available for each oscillator are
identical. There are also two further pages (Pages 1/8 and 2/8), with parameters common
to all three oscillators.
Per-Oscillator pages:
The default menu displays for Oscillator 1 are shown below:
OSCILLATOR 1 3/8
WaveMore BS sine h
FixedNote Off
BendRange +12
OSCILLATOR 1 4/8
Vsync 0 h
SawDense 0
DenseDet 64
More Waveforms
Displayed as: WaveMore
Initial value: BS sine
Range of adjustment: Wide range of waveforms
Peak includes a wavetable of 17 x 5 waveforms. The WaveMore parameter selects the
row of the wavetable the oscillator uses when Wave
10
is set to more. Note that the
wavetable column (or pair of adjacent columns) in use is determined by the setting of
Shape Amount
14
.
Single Fixed Note
Displayed as: FixNote
Initial value: Off
Range of adjustment: Off, C# -2 to E 5
Some sounds need not be chromatically-dependent. Examples would be certain
percussion sounds (e.g., bass drums), and sound effects, such as a laser gun. It is possible
to assign a fixed note to a patch, such that playing any key on the keyboard generates the
same sound. The pitch on which the sound is based may be any semitone note in a range
of over eight octaves. With the parameter set Off, the keyboard behaves as normal. With it
set to any other value, every key plays the sound at the pitch corresponding to the value.
Pitch Wheel Range
Displayed as: BendRange
Initial value: +12
Range of adjustment: -24 to +24
A keyboard pitch wheel can vary the oscillator pitch by up to two octaves, up or down.
The units are in semitones, so with the default value of +12, moving the pitch wheel up
increases the pitch of the notes being played by one octave, and moving it down takes
them down an octave. Setting the parameter to a negative value has the effect of reversing
the operating sense of the pitch wheel. You will find that many of the factory Patches have
this parameter set to +12 to allow a pitch wheel range of ±1 octave, or to +2 for a range of
±1 tone.