Korg Poly 6 Owner's Manual

KORG POLYSIX

PROGRAMMABLE POLYPHONIC SYNTHESIZER

Owner’s Manual

Congratulations and thank you for purchasing the new Korg PS-6 "Polysix" Programmable Polyphonic
Synthesizer.
This versatile six-voice synthesizer offers the wide range of sounds and enormous ease of use that only a
programmable synthesizer can offer, at a revolutionary price.

Handling precautions

• Always be sure to use the correct AC line voltage. If line voltage is 90% or less of rated voltage, S/N ratio

and stability will suffer. If you have any reason to believe the AC voltage is too low, have It checked with a
voltmeter before you turn on the power supply switch.

• Do not use any type of plug except for standard phone plugs (guitar type) in the KORG POLYSIX input and

output jacks.

• Avoid using or storing your KORG POLYSIX in very hot, cold, or dusty places.

Important note

Because this unit em ploys a mi croprocessor, abnorm al perf ormanc e may occur if you switch the power on too
soon after turning it of f . S hould t his occur, turn off the power, wait about ten seconds, then t urn the power back on
again.

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Features

32 programs stored in memory allow the user to create his own sounds for instantaneous recall at the push of a
button.

Full edit capabilities allow the user to make temporary changes to any program, and to move programs about in
memory.

Rapid, 8-second Cassette Tape Interface capabilities provides unlimited additional program storage, allowing you
to create program libraries for later use.

Both UNISON and POLY modes, to create incredibly fat six-VCO soloing and bass sounds as well as versatile six
voice polyphonic sounds.

Built-in full featured ARPEGGIATOR, with 3 selectable patterns and ranges, and with automatic "Latch" mode.

CHORD MEMORY memorizes intervals and chords, to produce exciting parallel harmonies by depressing single
keys. Memorized chords can be arpeggiated as well. HOLD sustains notes and chords indefinitely.

Programmable Modulation and Chorus/Ensemble effects create rich, fat sounds.

Lightweight 11.5kg instrument with 5-octave, 61 note keyboard plus Pitch Bend and Mod Wheels, for expressive
playing.

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Connections

Rear panel facilities

1) FROM TAPE TO TAPE

For connecti on to a tape recorder. This int erfac e lets you store unli mi ted sets of progr ams on tape. T hese can
then be loaded back into the synthesizer’s programmer as needed ev en in the middl e of a set. Connect FROM
TAPE to the recorder’s output jack (li ne out, earphone, or headphone terminal). Connect TO TAPE to the tape
recorder’s input jack (line in, m ic in, etc.) . Set switches to HIGH or LOW positions as needed to matc h recorder
input and output levels. HIGH is line or earphone level; LOW is microphone level.

2) CHORD MEMORY

Foot switch (S-1, PS-1, etc.) i nput jack for rem ote control of CHO RD MEMORY, so you do not have to press
the key assign mode switch. Par t icularly useful for putting chords in the memory when you ar e using both hands to
finger t he chord. A chord of up t o six notes can be m em oriz ed and t hen t he sam e str ucture can be reproduced by
playing single keys.

3) ARPEGGIO TRIG IN

Lets you use an external devi ce to control arpeggio tem po. A trigger out put from a rhythm box , sequencer, or
synthesizer may be connec ted to this jack. The tri gger should be negative- going (short to ground) . There is an
internal high impedance pullup to +5V.

4) VCF fcM IN

For external cont rol over VCF cutof f f requency (using MS-01, -04 f ootpedal , et c.). T his v ari es the ti m bre of the
sound, and permits "waa-waa" pedal effects when VCF is set at medium-high resonance.

5) PHONES

The phone jack is not silences by setti ng the front panel "OUT PUT" switch to OFF. This makes checking or
modify sound programs less obtrusive during recording or performance.

6) OUTPUT

High level or low level, controlled by front panel switch.

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Features and Functions

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PROGRAMMABLE CONTROLS (CAN BE STORED IN MEMORY)

VCO

The Voltage Cont r olled Oscillator (VCO) is the basic sound source for the synthesizer. There are 6 VCOs in the
Polysix, one per voice. The VCO waveform you select has a large effect on the timbre or tone quality of a
particular sound. The VCO may be set to operate in several different octaves, extending the range of the
keyboard. Pulse width modulation and Sub O SC tones are included, allowing a wide range of fat, satisfying sounds
to be produced.

OFF
1 OCT
2 OCT

OCTAVE WAVEFORM PW/PWM PWM SPEED SUB OSC

VCO

1) OCTAVE

This control has thr ee settings, 16’, 8’, and 4’. At the 8’ setting, t he mi ddle A on the keyboar d produces A440
(with Tune control set properly). 16’ and 4’ settings produce sound one octave lower and one octave higher,
respectively. The keyboard is therefore extended to the equivalent of a 7 octave range.

2) WAVEFORM
A. Sawtooth

This waveform is rich in both ev en and odd harmonic overtones. Because of this, the VCF can be used to
"shape" the tone color ov er a wide range by selectiv ely emphasizing di fferent harmonics of the waveform (see
VCF section for more details). Sawtooth waveforms are good for bass, strings, brass, and many other sounds.

B. PW/PWM (Pulse Width/Pulse Width Modulation)

These settings produce v ari ous types of r ectangul ar wav ef orm s, such as square waves, pulse wav es, "chorus",
etc., depending on t he setting of the PW/PWM and PWM SPEED controls. An extremely wide range of sounds are
available using these controls.

• PW Waveform

The width, or "duty cycl e" of the VCO wavef orm may be v aried manually using the PW/ PWM cont rol (PW M
SPEED has no effect in this position). At 0, t he VCO waveform is square wave (50% duty cycle), and possesses
the typical dull and "hollow" sound of the clarinet (only odd harmonics are present). Advancing the PW/PWM
control reduces the duty cycle, and hence the width of the VCO waveform . This produces a dramatic shif t i n the
tone qualit y towards a brighter and more "nasal ly" sound simil ar to oboe or harpsichord. At 8 or abov e t he pulse
width becomes so narrow as to collapse, which produces sound and in ef fect shuts off the VCOs. This is useful
when the VCFs are used as sound sources in their self oscillating mode.
Note: The SUB OSC tone is not shut off when the VCO is shut off due to zero pulse width.

• PWM Waveform

The width of t he VCO pulse wav eform is conti nuously changed, or " modul ated" by a v ariabl e speed oscillator.
This creates a fat "chorusing" t ype of sound, sim il ar to m ulti ple oscillators due to the constantly shif ting harm onic
balance. The PW /PWM control now determines the depth of the effect. At 0, there is no modulation (constant
square wave). Between 8 and 10, m odulation dept h is so great that the VCO shuts of f part of t he tim e (because
pulse width becomes 0 for part of each cycle). The speed of the ef fect is control led by the PWM SPEED knob.
The PWM oscillator is completely separate from the MG oscillator used for vibrato (see MG section), thus allowing
vibrato and PWM effects to occur simultaneously.

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3) PW/PWM

This controls the pulse width of the PW waveform, and the modulation depth of the PWM waveform (see

above).

4) PWM SPEED

This controls the speed of the modulation eff ect in the PWM wavef orm (see abov e) . It has no ef f ect on t he PW

waveform.

5) SUB OSC

This switch allows you to add a second tune either one octav e or two octaves below the VCO pi tch. This is
useful for produci ng fatter and full er sounds, particularly wit h solo or base Unison playing, organ sounds, and f ull
orchestra effects, etc.

While the waveform of both sub oscillator tones is a square wave, a phenomenon called "waveform
staircasing" causes the 1 octav e sub tone to take on much of the t imbral quality of the pri mary wav eform. This
makes it sound li ke an octav e "duplicat e" of the m ain wavef orm. W it h a sawtooth as the main wavef orm, a ver y
full String Orchestra pat ch can be created using this princi ple, many other sounds can also be enhanced in this
fashion.

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VCF

The VCF is perhaps the singl e most ex pressive m odule i n the Poly six. I ts basic f unction i s to m odif y t he tonal
quality (timbre) of the waveforms produced by the VCOs by eliminating certain harmonics (overtones) and
emphasizing other ones. Understanding how to use it is a key part of getting the most of your instrument.

There are 6 VCFs in the Polysix, one for each voi ce. Each VCF is a 4 pole, 24dB/ octave l ow pass filt er with
vol tage control led cut off f requency, v ari able resonance, posit iv e and negati v e EG modul ation ( "env elopi ng"), and
variable keyboard tracking. Each of these terms will be explained in detail below.

How does a filter modify timbre? There are two basic functions: cutoff frequency and resonance.

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RESONANCE EG INTENSITY KBD TRACKCUTOFF

1) CUTOFF

The cutof f f requency i s the point i n the audio spectrum where the f ilt er starts to af fect sounds passing through
it. The Polysix filters are term ed Low Pass, which means that they pass frequencies which are lower than the
cutoff point.

Any frequenci es above the cutof f frequenc y of the fi lter are progressiv ely rolled of f, or reduced in level . The
higher a fr equenc y is above the cutoff point, the more i t gets rolled off. This rolloff c an oc c ur at dif ferent rat es. The
Polysix fi lters hav e a 24dB/oc tav e roll off . T his means that a harm onic an octav e abov e the cutof f point would be
about 16 tim es softer com ing out of the f ilter than going i n. At two octaves abov e the cutof f point, a harmonic
would be about 256 times softer! This very sharp rolloff hel ps to produce real isti c i m i tati ons of m ost instrum ent s, a
wide vari ety of punchy synth voi cings, and many special eff ects. Since the c utoff point can be v aried throughout
the audio spectrum, you can choose to remove no harmonics, upper harmonics only, everything but the
fundam ental, or anything i n between. It can also remov e ev erything, si lencing the instrument, if t he cutoff point
goes much below the fundamental pitch.

There are fi ve ways to v ary the cutof f f requency of t he six VCFs: m anually, via t he VCF CUTOFF control; or
automati cal ly v i a each voice’s Envel ope Gener ator, the Key board Trac king function, or t he M odulat ion G enerator;
or vi a any external devi ce plugged into t he rear panel VCF fcM IN jack. The act ual cutof f frequency of t he VCF
will be proportional to the sum of the voltages (control signals) from these five sources at any moment.

VCF CUTOFF control

This determ ines the ini tial cutof f f requency of the f il ter. A t 0, the cut off is so low that no sound will be passed.
As you turn the control cl ockwise (towards higher num bers), the c utof f frequency increases and the note will begin
to sound, first with a dark, muted t im bre and then with a bri ghter one. At 10, the cutof f point i s abov e any audible
harmonic and the sound will be very bright.

VCF

2) RESONANCE

The second way that a filter modifies timbre is by adding resonance, (also known as "Q", "Peak", or
"Emphasis") at the cutoff point. Resonance is useful for a wide variety of sounds, such as organ, french horn,
classic synth bass and lead sounds, and many special ef fects. The RES ONANCE control all ows you to vary the
amount of resonance from 0 to self-oscillation.

At 0, there is no resonance, and frequenc ies abov e t he cutoff point are rol l ed of f smoot hl y. Changi ng the cut of f
point with no resonance simply varies the brightness or high frequency content of the sound.

Advanci ng the Resonance control cloc kwise (towards higher numbers) creates a resonant "peak" which serves
to strongly emphasize the frequenci es near the cutoff point (f requencies abov e the cutof f point ar e still rolled off).
This results in much more dramatic changes to the timbre of the sound. Medium resonance produces the
characteristic "waa-waa" sound when the filter cutoff is swept by the EG, footpedal or manually.

At high resonance, the f il ter will self-oscillate, producing a pure sine wave at the cutof f frequenc y. Thi s can be
used as a second sound source along with the VCO, or by itself if the VCO is shut off. The purest tone is
generated at about 7.

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3) EG INTENSITY

This controls how much the cutof f f requency i s v aried by the E G. It also determ ines whether the fi lt er is swept up
(positiv e modul ation) or down (negativ e modul ation) duri ng the attack phase of the EG . Max imum seep depth i s
plus or minus 10 octav es. W ide sweep depth are usually associated wit h dramatic effec ts, "electroni c" lead bass
sounds, clav type sounds, etc. Small sweep depths are often used to add a subtle extra dimension to more
"natural" sounds like french horn, woodwinds and other orchestral sounds. Howev er, there are certainly no har d
and fast rules and anything that sounds good to you should be used freely.

4) KBD TRACK

This controls the degree to which the f ilter "tracks" the keyboard, over a range of approxi mately 0% t o 150%.
Keyboard tracking is an extremel y useful f uncti on in which the V CF is made t o "f ollow" the note as i t is played on
the keyboard. This produces more even and real istic sounds by insuring that the tonal qual ity (ti mbre) of a giv en
sound remains constant over the ful l 5 octav e range (100% tracking). W ithout key board tracking, a giv en sound
played at "C" would sound bright and buzzy at the lowest "C", and muted or even non-existent at the highest "C".

The Polysix also all ows deliberate ov er- and under-t racking. This produces sm ooth and control led t one quali ty
changes as you move up and down the keyboard, for special effects, or to simulate instrument with changing
timbr es (e.g., many orchestral and keyboard instruments). At settings of approximatel y "7", the VCF fol lows the
note on a 1 for 1 basis (100%). Below 7, the VCF in eff ect "legs behind" the note pl ayed; this causes notes to
sound brighter as you go down in pitch, and rounder or mell ower as you ascend. Conversely , at setti ngs above 7,
the VCF cutoff increases "faster" than does the keyboard pitch, which causes notes to sound brighter as you go up
in pitch and dar ker as you go down. The furt her the control is f rom 7, the more pr onounced thi s tonal change wil l
be.

When the VCFs are self-oscillated and used as sound sources, the KBD TRACK contr ol allows you to "play" the
fil ters f rom the k eyboard as if they were regular oscillators (100% tracking). Addi tionall y, special scal es known as
Microtonal (e.g., "quartertone") and Macrotonal can be created at settings less than, or greater than 7,
respectively.

Variable keyboard tracking is extremely useful in producing realistic instrumental sounds, and in helping to
make any particular program sound good over a full five octave keyboard range.

MG (with MOD switch set to VCF)

This prov ides repetitive filter modulation or automatic " waa-waa" effects. Low settings of the MG LEVEL control
can give a subtle but very useful animation to the sound.

External control voltage (MS-01 pedal, etc.) applied to VCF fcM IN jack (nominal sensitivity is 1V/octave).

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VCA

The voltage controlled Amplif ier (VCA) controls the amplitude (v olume) of the sound. It is used to produce

volume contours (volume changes over time) similar to the timbre or tone color changes produced by the VCF.

There are 7 VCAs in the Polysix, one for each voice plus one overall VCA for the programmable attenuator.

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EG

MODE ATTENUATOR

VCA

1) MODE

In the EG position, volume changes are determined by the EG, for fully contoured effects.

In the lower position, a simple on-off gate-type envelope is produced (like an organ). This envelope is not
related to the EG settings in any way, and allows the VCA to be env eloped separately from the VCF. This can
produce much more "punchy" sounds, especially for brass and other sounds using heavy filter sweeps.

2) ATTENUATOR

This controls the overall volume of a given program over a 20dB range relative to t he other programs. I t can be
used to prevent jarring changes in volume when you change programs (e.g., from a flute patch to a massive
orchestral patch). It can also be used to preset "lead" and "rhythm" volume changes, if desired.

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