Korg Poly-61

Analogue polyphonic synthesizer

Poly-61
Poly-61
Manufacturer	Korg (Keio Electronic Laboratories)
Dates	1982-1986
Technical specifications
Polyphony	6 voices
Timbrality	Monotimbral
Oscillator	2 DCOs per voice
LFO	1/2
Synthesis type	Analog Subtractive
Filter	1 low-pass per voice
Attenuator	1 VCA per voice 1 ADSR envelope per voice
Storage memory	64 patches
Input/output
Keyboard	61 keys
External control	Poly-61M has MIDI

The Korg Poly-61 (PS-61) is an analog programmable polyphonic synthesizer released by Korg in 1982,^[1] as a successor to the Polysix. It was the first affordable synthesizer to feature two oscillators per voice, and was Korg's first largely "knobless" synthesizer, replacing the traditional knobs and switches found on the Polysix with a series of parameter selectors and two incrementing buttons that allowed the user to program sounds one section at a time.^[2]

The Poly-61 introduced digitally-controlled analog oscillators (DCOs), a year after the Roland Juno-6, replacing the Polysix's voltage-controlled oscillators (VCOs). With 64 memory positions, it offered double the patch memory of its predecessor but lacked the Polysix's onboard effects. In 1984, the Poly-61M was launched, adding basic MIDI capabilities.

Sounds and features

The Poly-61 features two digitally controlled oscillators (DCOs) per voice. DCO1 delivers sawtooth, square, and pulse width modulation (PWM) waveforms. DCO2 generates sawtooth and square waveforms and can be slightly detuned from DCO1, or by specific musical intervals such as a third, fourth, minor third, or fifth.^[2] The voltage-controlled filter (VCF) includes standard controls for cutoff frequency, resonance, keyboard tracking, and envelope modulation. The VCF has limited parameter settings, offering a simple on/off for keyboard tracking and just eight options for resonance and envelope intensity.

The audio signal path culminates in a voltage-controlled amplifier (VCA), controllable via the ADSR envelope generator or an external CV/Gate pulse. The Poly-61's LFO, referred to as a 'modulation generator,' produces a simple triangle wave with a variable delay, and can modulate both the DCOs and the VCF.

Unlike the separate pitch and modulation wheels of the Polysix, the Poly 61 features a full joystick with variable pitch bend and control over an additional independent LFO, which can modulate DCO pitch or VCF cutoff.

The Poly-61 features a chord memory function that captures and replicates any chord played, with a hold function that operates in both polyphonic and chord modes, supported by an input jack for a release foot pedal. Additionally, it includes a straightforward arpeggiator with dedicated controls, which can be used alongside the chord memory for creating complex sequences.

Reception

The Poly-61 was not as well received as the Polysix, with criticism levelled to its push-button programming interface, the perceived lack of warmth from its digitally-controlled oscillators (DCOs) compared to the Polysix's voltage-controlled oscillators (VCOs), and the coarsely quantised resolution of the digital programming system.^[3] The Poly-61 also lacked the on-board effects of the Polysix.

Crucially, the Poly-61 was released just before the introduction of MIDI, and still used old style analog voltage trigger outputs to interface it with sequencers and drum machines (although this was addressed by the later addition of MIDI in the Poly-61M). However, it would be the release of the all-digital Yamaha DX7 just a few months after the Poly-61 that would quickly erode its market appeal. The Poly-61 was replaced in 1985 by the DW-8000 which still used a partially analog architecture. It was not until the revolutionary Korg M1 six years later, that Korg returned to the top of the class with the first sample-based digital workstation synth.

References

^ "POLY-61 Programmable Polyphonic Synthesizer (1982-11)". Korg Museum, Sound Make Up. Korg Inc.
^ ^a ^b "Korg Poly 61". One Two Testing. United Kingdom: IPC Magazines Ltd, Northern & Shell Ltd. Dec 1982. p. 77. Retrieved 2024-03-15.
^ Reid, Gordon (October 2002). "The History Of Korg: Part 1". Sound On Sound. Retrieved 2024-03-15.