Korg OASYS

Infobox_synthesizer


image_caption = Korg OASYS
synth_name = OASYS
synth_manufacturer = Korg
synthesis_type = PCM, Wave Sequencing, Vector, Physical Modelling,
Sampler, Analog Modelling
polyphony = 172 for HD-1, CX-3, & PolysixEX; 96 for AL-1;
52 for MOD-7; 48 for STR-1 & MS-20EX
(all maximum; may vary depending on other
sounding voices and effects)
timbrality = 16
unison = up to 16 voices with spread, detune, and thickness functions. Polyphonic unison available
oscillator = depends on synthesis engine
filter = depends on synthesis engine
attenuator =
left_control = 2x Joystick, 2x Switch, Ribbon, KARMA
portamento = yes (depends on EXi)
lfo =
keyboard = 76 or 88-key| velocity = yes| aftertouch = yes| memory = 1GB RAM, upgradable to 2GB. No physical ROM.
Preloaded samples include 314MB "ROM"
(loaded into RAM automatically at startup),
and optionally-loaded 313MB EXs1 "ROM Expansion"
& 503MB EXs2 "Concert Grand Piano."
0MB to 1.5GB available for user samples,
depending on memory configuration and loaded EXs.
Internal 40GB HDD.
ext_control = MIDI
fx = 12 insert, 2 master, 2 total
dates = 2005 -
price = $8000 - $8500
The Korg OASYS is a workstation synthesizer released in early 2005, 1 year after the successful Korg Triton Extreme. Unlike the Triton series, the Oasys is implemented on a custom Linux operating system and is designed to be arbitrarily expandable via software updates, with its functionality limited only by the PC-like hardware.

Features

The standard Oasys comes with a hardware similar to many personal computers:
* 2.8 GHz Pentium 4 CPU
* 40GB hard disk drive
* 1GB DDR RAM, user-expandable to 2GB
* 10.4" LCD touch screen

It features Korg's OASYS (acronym for Open Architecture SYnthesis Studio) technology, which allows multiple synthesis engines to be used simultaneously. The OASYS also includes second-generation KARMA technology (with the first generation having first appeared in the Korg KARMA). It has either a 76-key synth-action or 88-key hammer-action keyboard.

ynthesis engines

As of December, 20 2007 the latest version of the OASYS OS is 1.3.1, featuring the following synthesis engines:

# HD-1: A PCM synthesizer, with 628 MB of preloaded samples and Wave Sequencing
# AL-1: A 96-note polyphonic virtual analog synthesizer (84 notes in previous versions of the OS)
# CX-3: A modelled tonewheel organ based on the current CX-3
# STR-1: A plucked string physical model
# LAC-1: Optional bundle ($250) including two virtual analog synthesizers, the PolysixEX and MS-20EX, which are updated models of the vintage Korg Polysix and Korg MS20.
# MOD-7: Combines Variable Phase Modulation (VPM), waveshaping, ring modulation, PCM sample playback, and subtractive synthesis in a patchable, semi-modular synthesizer.

HD-1

HD-1 Program

The HD-1 is a sample+synthesis engine with a two "oscillator" structure. In addition to the two "oscillators," an HD-1 Program contains a Vector Envelope, Common LFO (per-Program as opposed to per-voice, similar to the modulation LFOs in some early polyphonic analog synths), two common key tracking generators, KARMA settings, and effects.

HD-1 Oscillator

Each "oscillator" consists of a sample playback oscillator, dual multimode filter, nonlinear "drive" and low boost section, amp, and pan. The sample playback oscillator has four velocity zones, each of which can play a mono or stereo sample or a Wave Sequence. Velocity zones can overlap or crossfade. Korg claims very low aliasing distortion, due to the use of bandlimited interpolation.

Wave Sequencing

Wave Sequences were first introduced on Korg's Wavestation synthesizer, released in 1990. Wave Sequences allow a single note to play through a list of samples, one after the other, with or without crossfades, with other associated parameters changing for each sample, as listed below. This can create smooth, evolving timbres, or rhythmic effects. Internally, Wave Sequences are implemented by using two voices; voice A plays the first sample, voice B plays the second sample, voice A plays the third sample, and so on. Other synthesizers have featured concepts which are similar in some aspects, such as PPG wavetables, Synclavier resynthesis, and Ensoniq Transwaves and Hyperwaves (see the Ensoniq TS 10).

In the lists below, features new to the OASYS (in comparison to the Wavestation) are noted.

OASYS Wave Sequences include, for each step:

* The sample to play (mono or stereo)
* Sample start offset
* Reverse on/off
* The length of the step, in milliseconds or rhythmic value
* The crossfade time into the next step, in milliseconds
* Crossfade fade-in shape (256 steps, from log to exp)
* Crossfade fade-out shape (as above)
* Volume
* Transpose and fine-tune
* Two modulation ("AMS") value outputs, to control any modulatable synthesis parameters in the rest of the Program (e.g. filter cutoff or resonance, LFO speeds, etc.)

And, for the sequence as a whole:

* Time/Tempo mode (determines whether step durations will be in milliseconds or rhythmic values)
* Run on/off (enables and disables programmed durations and crossfades altogether; modulation from other sources can control the sequence directly)
* Key sync on/off (determines whether each note's Wave Sequence runs independently, or whether all notes sync together for lock-step rhythms)
* Swing and swing resolution
* Quantize Triggers on/off (adjusts note start times to match current KARMA/Sequence)
* Start step and start step modulation
* End step
* Loop start, end, and direction (forwards, backwards/forwards, backwards)
* Loop repeats
* Note-on advance (increments the start step for each played note)
* Position modulation (sweeps through the sequence manually)
* Duration modulation (changes the step durations)

Differences from the Wavestation

Additions to the original Wavestation implementation include time/tempo modes, sample-locked tempo synch, constant-time crossfades in tempo mode, fade-in and fade-out shapes, swing, trigger quantization and key sync, note advance, realtime duration modulation, control of reverse and sample start point per step, and modulation outputs.

EXi

EXi is a Korg acronym for "EXpansion Instrument." It refers to all OASYS synth models other than the HD-1, including the AL-1, CX-3, etc.

EXi Program

This is the Program structure for playing EXi. It is similar to that of the HD-1, but differs slightly in a few ways, such as:
* Allows selection of any two EXi for layering or splitting
* Adds a "Common" step sequencer, shared by all voices in the Program
* Adds audio input selection for each of the two EXi (currently used by MS-20EX and MOD-7)
* Adds transposition for each EXi

AL-1

Virtual analog synth engine.
* Two main oscillators with analog-style FM and sync
**Korg claims proprietary anti-aliasing technology, for no audible aliasing over standard 88-note range, with sync (but with drive and ring-mod off)
**Waveforms: Saw, Pulse, Saw/Pulse, Double Saw, Detuned Saw 1, Detuned Saw 2, Triangle, Square/Triangle
**Wave Morph and Pulse Width/Phase/Detune
* Sub-oscillator
* Audio input
* Noise generator with saturation and dedicated filter
* Ring modulation (Ring Mod, AM, Rectify, Clip)
* Mixer provides modulatable volume and filter a/b pan for osc 1, osc 2, sub osc/audio input, noise generator, and ring mod
* Per-voice, modulatable Drive (nonlinear distortion) and Low Boost (low eq)
* Dual resonant multimode filters, including "multifilter"
**Multifilter provides two separate sets of gain controls for lp, hp, bp, and dry signals, with modulatable crossfade between the two sets
* 4 EGs
* 4 LFOs
* 2 "AMS Mixers" (modulation signal processors)
* Per-voice step sequencer

CX-3

Stub.

TR-1

Stub.

MS-20EX

Stub.

PolysixEX

Stub.

MOD-7

The MOD-7 includes six VPM oscillators, plus a PCM oscillator, noise generator, audio input, two multi-mode filters, three 2-in/1-out mixers, and a 6-input main mixer - with a patch panel for routing them together. The MOD-7 is capable of producing classic FM keyboards and bells to rhythmic soundscapes, synth basses, and sparkling, epic pads.

Notable Users

*Pete Townshend - The Who
*Tuomas Holopainen - Nightwish
*Jordan Rudess - Dream Theater
*Keith Emerson - Emerson Lake and Palmer, Keith Emerson Band
* Tony Banks - Genesis
*Greg Phillinganes - session keyboardist, played with Toto 2005-2008
*Herbie Hancock
*Chuck Leavell - The Rolling Stones
*Sly Stone
*Derek Sherinian
*Michael Cretu - Enigma
*John Paul Jones-- at 2007 reunion of Led Zeppelin
*Murray Gold -Doctor Who composer (2005-?)

ee also

*Korg M3
*Wersi Open-Architecture-System
*Music workstation

External links

* [http://www.korg.com/ Korg Website]
* [http://www.karma-lab.com/oasys Karma-Lab Website - OASYS page]
* [http://karma-lab.wikidot.com/korg-oasys:start Karma-Lab Wiki - OASYS articles]
* [http://www.karma-lab.com/vp/klvp.html?ch=oasys Karma-Lab OASYS Video and Audio clips]
* [http://www.korg.com/oasys/EM_Review.pdf Electronic Musician magazine's review] - PDF file
* [http://www.korg.com/oasys/OASYSKBDRW.pdf Keyboard magazine's review] - PDF file
* [http://www.soundonsound.com/sos/nov05/articles/korgoasys.htm Sound On Sound magazine's review, part 1]
* [http://www.soundonsound.com/sos/dec05/articles/korgoasys.htm Sound On Sound magazine's review, part 2]
* [http://www.keyboardmag.com/story.asp?storycode=7833 Keyboard magazine article: The Making of the Korg OASYS]
* [http://www.soundonsound.com/sos/oct06/articles/korgstr1oasys11.htm Sound On Sound magazine's OASYS v1.1 and STR-1 review]
* [http://www.soundonsound.com/sos/apr07/articles/korglegacy.htm Sound On Sound magazine's OASYS v1.2 and LAC-1 review]
* [http://digitalmedia.oreilly.com/2005/11/09/inside-the-korg-oasys.html O'Reilly Digital Media - Inside a Luxury Synth: Creating the Linux-Powered Korg OASYS]
* [http://www.soundclick.com/theartofsound/ The Art Of Sound Website (Audio Demos)]
* [http://www.sweetwater.com/feature/korg/ Understanding the Korg OASYS] with video interviews and media gallery
* [http://www.vanille.de/extras/oasys/oasys.html History of the old OASYS project]
* [http://www.korgforums.com Korg Forums Website]
* [http://www.karma-lab.com/forum/oasys Karma-Lab OASYS forums]