Korg Oasys Operation Manual page 20

Introduction to OASYS
the damper pedal and strike a key, the sympathetically
vibrating strings will also sound, faithfully replicating
the depth and transparency of an acoustic piano.
Staple ensemble sounds such as strings and brass use
stereo sampling to capture their natural spaciousness,
with a rich variety of articulations such as tremolo,
pizzicato, and sforzando, as well as four‐level velocity
switching and crossfading to ensure a natural range of
expression.
Reed instruments such as sax and oboe were sampled
for extended times to include natural‐sounding vibrato
produced by the player.
The drums that are so important for the overall
character of a track also use stereo sampling, with long
samples that capture the natural decay and four‐level
velocity switching and crossfading for natural
dynamics.
Wave sequencing – generating textured tones or
rhythmic sounds
In addition to simply playing back the PCM waveform,
the HD‐1 High Definition Synthesizer's oscillators also
support Korg's proprietary Wave Sequencing
functionality.
Wave sequencing successively switches through PCM
waveforms, crossfading between different sounds to
create textured tones or rhythmic sound designs. Made
famous on Korg's WAVESTATION, wave sequencing
has been redesigned to be even easier and more
creative than ever.
You don't have to stop with simply playing back PCM
waveforms in succession – you can freely specify the
timing, length, and pitch of each waveform. The timing
at which waveforms are switched can even be
synchronized to the tempo. You can also use AMS
(Alternate Modulation Sources) to obtain sound design
possibilities that are completely unthinkable for a
conventional PCM synthesizer; for example, you can
use the output of an envelope generator to control the
timing at which waveforms are switched.
Advanced Vector Synthesis – create not only
sounds, but also sound fields
The OASYS includes Advanced Vector Synthesis,
which lets you synthesize spatial sound‐fields.
In Combination mode, you can assign each timbre to
one of the four directions (up, down, left, or right), and
use the front‐panel Vector Joystick to control the
timbre volumes or effects.
In Program mode, you can use this for realtime control
over the balance between oscillators 1 and 2 or for
controlling effects, giving you a powerful tool to create
sounds with dynamic movement.
In addition to controlling the Vector position manually
in realtime, you can use the five‐point Vector Envelope
to control vectors automatically. For each point, you
can specify the Vector position, how long the envelope
will hold at the point, and how long it will take to
transition to the next point. Transition and hold times
can use either absolute time, or rhythmic values
synchronized to the system tempo.
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Ultra high-precision filters are the core of sound
design
Because of its power and conceptual ease of
understanding, subtractive synthesis (the technique of
creating sound by selectively removing portions from
an overtone‐rich waveform) has become the standard
for synthesizers today. One of the most important
components of subtractive synthesis is the filter.
The filter section of the HD‐1 High Definition
synthesizer provides four filtering types (low pass,
high pass, band pass, and band reject) and four types
of routing (single, serial, parallel, and 24 dB).
The amazing power of the OA (Open Architecture)
synthesis system produces natural and beautiful
filtering that does not weaken the sound, delivering
smooth filter sweeps and resonance.
The amp of the OASYS contains driver circuitry that
covers a wide range of distortion, from the mild and
warm overdrive characteristic of classic analog
synthesizers, to the sharp distortion produced by
audio signal feedback.
In addition, the key tracking generator allows the
filtering to vary according to the keyboard range; you
can apply subtle filtering for convincing simulation
sounds, or aggressive filtering that produces drastic
changes in filtering as you play up or down the
keyboard.
Dive into an ocean of creative potential – flexible
modulation routing, EG, LFO, and AMS
OASYS takes advantage of its lavish amount of
available processing power to produce ultra‐fast and
ultra‐smooth EGs (envelope generators) and LFOs.
EGs allow you to specify how the sound develops over
time, from its onset to its end. The HD‐1 High
Definition Synthesizer lets you adjust the curvature of
each EG stage (attack, decay, slope, and release), giving
you detailed control over how the tone and volume
change over time, and making it possible to program
anything from simulated acoustic sounds to vintage
synthesizer sounds in the utmost detail.
The HD‐1 provides a common LFO for each timbre
and two LFOs for each voice. You can choose from
eighteen types of LFO waveform, and also adjust the
phase of the waveform, the curve, and the center value
of the amplitude to create distinctively modulated
sounds that have never been heard before. Since the
waveform itself is generated with extremely high
precision, you can create perfectly smooth sweeps.
You'll appreciate the LFO's tightness and accuracy not
just at high speeds, but also for low‐speed modulation.
It goes without saying that you can also apply key sync
so that the same modulation occurs each time a note is
played, or synchronize the modulation speed to the
tempo to create rhythmical tonal changes.
Korg's AMS (Alternate Modulation Sources) give you a
rich array of modulation possibilities, with 52 different
modulation sources you can use to control the sound in
complex ways. The OASYS takes this classic Korg
feature even further, via the AMS Mixers. These let you
create even more detailed modulation designs, such as