The Poly-61 is a programmable polyphonic synthesizer

Synthesizer

A synthesizer is an electronic instrument capable of producing sounds by generating electrical signals of different frequencies. These electrical signals are played through a loudspeaker or set of headphones...

 released by Korg

Korg

is a Japanese multinational corporation that manufactures electronic musical instruments, audio processors and guitar pedals, recording equipment, and electronic tuners...

 in 1982, replacing the Polysix

Korg Polysix

The Korg Polysix is a six voice programmable polyphonic synthesizer released by Korg in 1981.- Features :The synthesizer's main features are six-voice polyphony , 32 memory slots for patches and cassette port for backing up patches, and an arpeggiator.On its release it was, along with the Roland...

. It was notable as it was the first Korg synthesizer to feature a pushbutton user interface, dispensing from the Polysix's knobs and switches. Later versions of the instrument are called the Poly-61M and have basic MIDI implementation.

Oscillators

The Poly-61 uses DCO

Digitally-controlled oscillator

A digitally controlled oscillator or DCO is a hybrid digital/analogue electronic oscillator used in synthesizers. The name is an analogy with "voltage-controlled oscillator"...

s and has two per voice. DCO1 provides sawtooth, pulse, and PWM

Pulse-width modulation

Pulse-width modulation , or pulse-duration modulation , is a commonly used technique for controlling power to inertial electrical devices, made practical by modern electronic power switches....

 waveforms. DCO2 has only sawtooth and square.

Filter

The filter has the usual controls for cutoff, resonance, keyboard tracking and envelope amount. Some of these are rather limited by the poor parameter resolution. Keyboard tracking is simply "on" or "off" for example, and resonance and envelope level (here labelled "EG Intensity") have only 8 settings.

Output

The final component in the audio path is a VCA. It can be driven by the envelope generator or a CV/Gate

CV/Gate

CV/Gate is an analog method of controlling synthesizers, drum machines and other similar equipment with external sequencers. The Control Voltage typically controls pitch and the Gate signal controls note on/off....

 pulse.

Envelope generator

The envelope is an ADSR type. All parameters can be set to any of 16 levels.

LFO

The LFO (known as a 'modulation generator' on the Poly-61) is a simple triangle wave that can be routed to the DCOs or VCF. It has a variable delay before it is triggered

Differences from the Korg Polysix

Although similar in many ways, there are key differences between the two:

• Many parameters on the Poly-61 have limited resolution of 8 steps, whereas Polysix parameters have 256 step resolution.
• The Poly-61 has DCOs versus VCOs on the Polysix.
• The Poly-61 has two oscillators versus one on the Polysix.
• The Poly-61M has MIDI.
• The Poly-61 has 64 memories, instead of 32 on the Polysix.
• The Polysix has an analog effects board, whereas the Poly-61 has no effects.

External links

• http://www.keyboardmuseum.com/ar/k/korg/p/p61.html
• http://www.vintagesynth.com/korg/poly61.shtml