Korg Poly-800 (1983)
Polyphonic Synthesizer

Affordable poly-synth based on DCO oscillators with internal step sequencer.

KEYBOARD 49 keys with no velocity. Main panel features a segmenst display, 3 sliders, 19 button and 1 data slider.

Back panel terminal connectors:
- Midi Interface (no Thru port)
- main signal out
- headphones out
- tape Interface
- switch tab memory protection
- pedalswitch input for program up.

Power supply is external PSU with 9V AC/DC -)+ polarity.

 

VOICE main unit 8 bits controller CPU Intel 8050 family. Oscillator DCO is based on MSM5232 chip, well-known for some '80 arcade games. The IC 5232 generates 8 digitally controlled oscillators assignable in 2 different manners:
- double mode: 2 x 4 voices for a thicker richer sound
- whole mode: 1 x 8 voices for full polyphony.
TECH: Poly-800 cannot be computer- edited since it cannot handles Midi Exclusives.

 

 

DCO an oscillator features 2 summable waveforms saw and square plus 4 additive harmonic octaves heights at 16' 8' 4' 2' + 1 white noice generator.

 

ENVELOPE there are 3 EGs:
- 1 DCO1 amplitude: 6-stages ADBSSR
- 1 DCO2 amplitude: 6-stages ADBSSR
- 1 VCF: 6-stages ADBSSR.
The ADBSSR stands for: Attack, Decay, Break point, Slope, Sustain and Release.

 

 

LFO there are 2 triangle-shapped modulators:
- MG1 modulates FILTER VCF
- MG2 modulates DCO pitch.
The modulator is triggered by joystick control with possible delay start function.

 

 

FILTER a limited paraphonic filter based on a single NJM2069.
The chip is a resonant (but not up to self-resonance) analog 4 poles lowpass with cutoff, contour and possible polarity reverse.

 

 

EFFECTS analog stereo chorus board based on BBD 3209 + driver 3102.

 

SEQUENCER features a very basic 256 steps sequencer syncable to external Midi clock

MOD filter VCF values are quantized in 99 numbers but some nice guys made out a nice hardware modifications called "Moogslayer" adds 2 real-time knobs for cutoff filter and resonance. I did this mod once but to the laptop version EX-800 Moogslayer - you can listen to it in the DEMO section.

 

 

MEMORY:
- 64 RAM patches
- NO ROM memory
Memory is non-volatile if 6 x 1.5 V batteries are fitted- there is a custom modification to implement an internal lithium 3V like Cr-2032.
TECH: no Midi Sysex implementation, later corrected on desktop EX800 and revision model Poly800 Mk2.

 

 

 

RELATED FAMILY:

	POLY800 reverse key edition. Same with different outfit
	POLY800 II enhanced POLY800 with new design, sysex, battery CR2032 and digital delay.
	EX-800 Laptop version of poly800 mk1 with Midi thru and Midi sysex.

 

VST PLUGIN / SAMPLED VERSION there are some free and commercial samples set:

	name	price	link	demo
	Poly-850 then " X-POLY"	VST commercial
	Bedroomproducers	Free sample pack (includes various classic vintage synthesizers)

 

AUDIO DEMO

Machinery - all poly800 : overdub+drum + vocoder Roland SVC350 All poly800 + Volca beats drums shine on your strings moogish Moogslayer bassline ->more Demo at the POLY800 MK2 page just few demos, please do send some of your poly800 audio clips :)

VIDEO CLIP SELECTION ** Back in the 80s ** mod Synth Demo

 

 

MANUAL

SERVICE MANUAL

FACTORY PATCHES for tape player

original Brochure

original Brochure

original Brochure

original Brochure

original Brochure

CUSTOM poly800

Super CUSTOM "Frankenkorg"