Korg MS-20
From Wikipedia, the free encyclopedia
 |
|||
| MS-20 by Korg | |||
| Synthesis type: | Analog subtractive | ||
|---|---|---|---|
| Polyphony: | Monophonic | ||
| Timbrality: | Monotimbral | ||
| Oscillators: | 2 VCOs per voice | ||
| Filter: | 2 high-pass/low-pass | ||
| Attenuator: | 2 VCA 2 envelopes |
||
| LFO: | 1 | ||
| Keyboard: | 37 keys | ||
| Velocity sensitive: | no | ||
| Aftertouch: | no | ||
| External control: | CV/Gate | ||
| Memory: | none | ||
| Onboard effects: | none | ||
| Produced: | 1978 - 1983 | ||
The Korg MS-20 is a patchable semi-modular monophonic synthesizer which Korg released in 1978 and was in production until 1983. It was part of Korg's MS series of instruments, which also included the single oscillator MS-10, the keyboardless MS-50 module, and the SQ-10 sequencer. Additional devices included the MS-01 Foot Controller, MS-02 Interface, MS-03 Signal Processor, MS-04 Modulation Pedal and VC-10 Vocoder.
Although the MS-20 follows a conventional subtractive synthesis architecture of oscillators/filter/vca, its patch panel allows some rerouting of both audio and modulation, and it includes an external signal processor. This flexibility led to its resurgence during the analog revival of the late 90's.
Contents |
[edit] Audio path
[edit] Oscillators
The MS-20 has two VCOs. The output of VCO1 can be set to triangle, sawtooth or adjustable-width pulse. The output of VCO2 can be set to sawtooth, square, rectangle or "ring mod" which is in fact an exclusive-OR between the pulse output of VCO1 and the square wave output of VCO2. Although the pulse width of VCO1 is adjustable, there is no voltage control for this parameter and as a result pulse width modulation is not possible. The VCOs have Hz/V voltage control inputs.
[edit] Filters
There are two VCFs. Both VCFs are 12dB/oct Sallen-Key designs. Resonance ("peak" in Korg parlance) is adjustable but not voltage-controlled. The VCFs are connected in series, high-pass first and low-pass second. This allows both voltage controlled band-pass and notch responses to be constructed.
Originally, the filters used Korg's proprietary KORG-35 chip. Later, the filters were redesigned to use off-the-shelf LM13600 OTAs. MS-20 fitted with LM13600 filters have a small daughter board.
[edit] Output
The final component in the audio path is a VCA.
[edit] Modulation
The MS-20 also features a modulation generator section which is located next to EG1. This acts as the main control for the modulation being able to choose between 'waveform' and 'frequency' at which it modulates. There are cutoff frequency modulators under both the highpass and lowpass filter which control the rate at which the frequency modulator modulates the filter cutoff function on each of these filters, this is closely used with the main control panel of the frequency modulation to control waveform and frequency. Modulation can be heard sonically as a 'wobble' in the sound, the frequency controls in the modulation generator simply mean at what rate the sound 'wobbles', the higher the frequency, the faster the rate of 'wobble' or modulation. At this point this is where the sound becomes less like the original sound source and something unique using frequency modulation
[edit] Envelopes
There are two envelope generators. EG1 has Delay, Attack, and Release parameters, whilst EG2 has Hold, Attack, Decay, Sustain and Release. The envelope generators have S-trig trigger inputs.
[edit] Other sources and options
The MS-20 also includes an LFO with ramp up and down, triangle, square, and various pulse waveshapes. There is a noise source, a separate modulation VCA, a wheel controller, and a trigger button. It is possible to connect the MS-20 to a step sequencer like the SQ-10 (another product by Korg). This involves making use of the CV input and the trigger input which connects straight to the SQ-10, this means that the synthesiser and the step sequencer can work in synchronisation to play the notes when the next step of the sequencers pattern is triggered. In theory it is possible to connect any analogue sequencer to the MS-20 providing it has a trigger and CV input.
[edit] Musicians who have used the MS-20
The MS-20 has been used by bands and artists such as Soulwax, Air, A Flock of Seagulls, Liam Howlett of The Prodigy, Simian Mobile Disco, Digitalism, Shapeshifter, William Orbit, Electrosexual, Skinny Puppy, Greg Anderson, Orchestral Manoeuvres in the Dark, Eliot Lipp, Chicks on Speed, Severed Heads, Safety Scissors, Goldfrapp, Dubstar, Covenant, The Faint, Mr. Oizo, Zia McCabe of The Dandy Warhols, Foals, Klaxons, Legowelt and The Presets have also used an MS-20. Aphex Twin likes to put many of his sounds through the ESP (External Signal Processor), which is also used by Mira Aroyo of Ladytron.
Nicole Skeltys of Biftek and Steve Law of Zen Paradox and others played in an MS-20 only improvisational group called the MS-20 Arkestra in Melbourne on 6/6/06.
