The Roland Icon Series is a collection of articles looking back at the most popular and recognised Roland instruments. In over four decades, Roland has designed many world-first instruments like the first touch-sensitive keyboard and first guitar synthesizer.

Previous articles in the Roland Icon Series revisited the classic Roland Jupiter-8, the SH-101, the MRS-2 ProMars, the SH-2 Monophonic Synthesizer and the SYSTEM-100 Synthesizer. This article looks at the famed Roland Juno-106.

Contributed by Hannah Lockwood for Roland Resource Centre

THE JUNO SERIES

By the early 1980s, Roland had pioneered synth design with a now legendary range of monophonic, modular and polyphonic analog synthesizers. These included the aforementioned SH, System, MRS and Jupiter series. With the release of the Juno series in 1982, Roland continued to innovate with a new line of synthesizers that not only defined the sound of that decade, but provided a source of inspiration for musicians from all backgrounds. Our focus here, the Juno-106, was the third release in the Juno series of analog synthesizers which were manufactured and released during the early 1980s.

The first synthesizer in the Juno family, the Juno-6, was released in May 1982, marking the start of an incredible legacy that still continues today. The Juno series were the first synthesizers to use digitally controlled oscillators (DCOs) and the core part of this setup was the NEC μPD8253 chip (first used in an early electric piano called the EP-09). Continuing the polyphonic capability that Roland first utilised in 1979’s Jupiter-4, the Juno-6 offered six voices of polyphony and an array of onboard controls. Although it featured no MIDI and provided no patch memory storage, the Juno-6 is still coveted for its warm analog oscillators, distinctive chorus effect and superb filters. The Juno-6 did not feature any external control inputs or outputs, though did offer a VCF control input for sweeping the filter cutoff.

Similar in appearance, sound and internal architecture to the Juno-6, the Juno-60 was released in September 1982, offering new features that improved upon its predecessor. Patch storage memory was introduced, enabling the user to save up to 54 patches. It also featured the Roland Digital Control Bus (DCB) interface, which allowed the Juno-60 to be connected to other external instruments and sequencers. These additions made it favorable with live musicians and bands, who benefited greatly from the patch memory and connectivity.

February 1984 saw the release of the Juno-106, a direct descendant of the Juno-60 synthesizer. MIDI was introduced and patch memory was improved from 56 patches to 128, allowing for more expansive control. The simple up/down arpeggiator included on the earlier Juno models was replaced by a portamento feature. The Juno-106 offered the best of both the analog and digital worlds, and was one of the last great synthesizers to include a dedicated control for every parameter on the faceplate, for immediate access to all programming. Its ease of workflow and tactile interface made it popular with recording artists and live performers.

ONBOARD

The Juno-106 is a programmable, six-voice polyphonic, analog, subtractive synthesizer. With its relatively simple voice architecture, it is able to produce luscious soundscapes, rich basslines, strings, pads, pianos, leads and percussive sounds. Its intuitive interface and diverse sonic palette has inspired musicians from all styles and backgrounds.

Oscillators
The Juno-106 uses six digitally controlled oscillators, capable of producing a sawtooth, pulse and sub-octave square waveforms. DCOs were introduced into Roland synth design during the 1980s, as a means of eliminating inaccuracies such as pitch drift, which arose from the use of the completely analog VCOs in earlier synthesizers. DCOs provided a cheaper and more stable alternative to VCOs, without compromising the overall sonic character of the instrument’s analog sound. These were the same kind of control oscillators that were used in Roland’s famed JX-3P synthesizer.

The sawtooth waveform of the Juno-106 outputs directly from the DCO core, while the pulse wave is derived from the sawtooth, via a wave-shaping circuit. Even though these oscillators are digitally controlled and digitally stable, they produce true analog outputs with no digital stepping. Pitch is selectable via 16′, 8′, and 4′ settings. A square wave sub-oscillator and a noise generator are also provided, with individual sliders to control the levels for each parameter.

The Juno-106 features control for pulse width modulation (PWM). When the PWM switch is set to MAN, the pulse width can be manually set to a certain ratio. In this setting, the PWM slider controls the actual pulse width. When the PWM switch is set to LFO, the pulse width is controlled by the LFO signal. The PWM slider now controls the intensity of the LFO modulation.

Assign modes
The Juno-106 offers two Assign modes – Poly 1 and Poly 2. Poly 1 turns the Juno-106 into a six-voice polyphonic synthesizer, assigning one synth voice to each key that is pressed. This particular setting is generally suited to sounds with envelopes similar to a piano or a guitar and is recommended for standard use. Poly 2 mode is similar to Poly 1, the key advantage being that only the last note or notes played receive natural release length. This makes Poly 2 mode more suitable for performance with the onboard portamento effect. Pressing Poly 1 and 2 moves the Juno-106 into Solo Unison mode. In this mode, the Juno-106 acts as a monophonic synthesizer, with all six voices assigned to each key that is pressed.

Filters
Perhaps one of the most revered features of the Juno-106 is its 24dB/octave analog low-pass filter, which provides the instrument with much of its distinctively smooth texture and deep sonic power. The voltage controlled filter (VCF) features adjustable sliders for frequency and resonance level and can be modulated by one of the envelopes, the LFO, and keyboard tracking. Individual sliders for ENV, LFO and KYBD control the modulation level of the three sources. Using the KYBD control, the filter cutoff can track the keyboard, allowing for higher harmonics to be heard on notes with higher pitches.

The VCF has self-oscillating abilities, making it a vibrant and diverse analog filter. In addition to this, the Juno-106 also features a non-resonant high-pass filter (HPF), with four control positions and a dedicated slider for cutoff frequency.

The VCA of the Juno-106 can be switched between simple note gating or envelope controlled loudness, via a switch on the faceplate. A single invertible ADSR envelope can be assigned to the cutoff frequency of the filter, and can also be selected to control the VCA. A triangle wave LFO features controls for rate and delay and can be applied to both the DCO and VCF sections.

Control
The 106 was the first of the Juno series to offer MIDI capabilities, a feature which helped to elevate the Juno-106 from its predecessors at the time of its release. The back panel also features one set of 1/4” audio outputs, a stereo headphone jack output, a tune knob, patch shift and pedal hold jacks, a level switch, power ON/OFF, a memory protect switch and a MIDI function selector switch. The Tape interface located on the back panel allows the user to save and load patch programs onto a standard tape recorder via their respective jacks.

The onboard chorus effect of the Juno-106 was based on a set of bucket brigade delay (BBD) lines that were similar to other Roland products of the time, including the BOSS range of guitar pedals and effects units.

With its simple architecture – pulse and sawtooth waves, a square wave sub-oscillator, noise source, LFO, high-pass filter, VCF, ADSR and chorus effect – the Juno-106 has gone on to shape various music styles and genres. While other synthesizers offer more elaborate voice architecture, more complex envelopes and more diverse modulation capabilities, the relative simplicity of the Juno-106 makes its diverse sonic range quite amazing. Despite its limitations, it is still one of the most revered synthesizers of all time.

5 KEY FEATURES

The Juno-106 introduced some notable features to achieve its unique character sound.

1. MIDI

16 MIDI channels are available on the Juno-106 and MIDI SysEx Data is both transmittable and receivable from all sliders and buttons on the instrument. MIDI IN/OUT/THRU ports are located on the back panel. This allows for complete remote control and external sequencing capabilities. The Juno-106 offers three different types of MIDI modes, which can be changed via the MIDI Function switch on the back panel. These modes are:

• I – KYBD (Keyboard and Hold data only)
• II – KYBD + BENDER + PGM CHANGE (Keyboard, Hold, Bender, Patch selection data)
• III – ALL (All data, which includes SysEx). This allows for more advanced settings to be saved and changes to be made.

2. CHORUS

The Juno-106 features an onboard, stereo, two way, analog chorus unit, which produces its distinct character sound. The one-oscillator design left the Juno synthesizers sounding relatively thinner than their two voice counterparts. To make up for the single voice oscillators, Roland engineers employed a number of solutions to accommodate this design feature. The chorus effect provides a rich, spatial quality and is extremely effective in thickening sound sources. Few could predict that this chorus effect would go on to become a defining feature of the Juno sound, with legions of admirers worldwide. The Juno-106 offers two depths of chorus, with Chorus II creating a stronger effect than Chorus I.

3. DIGITAL CONTROL, ANALOG SOUND

The DCOs used throughout the Juno series had a vast impact on the sound and usability of the Juno-106. DCOs were first used by Roland on the Juno-6 and proved to be more reliable than their purely analog voltage controlled equivalents. A digitally controlled oscillator derives its pitch directly from the main microprocessor in the form of digital pulses. These pulses are electronically shaped to provide the character waveforms. Although they are digitally controlled, they still produce a true analog output and retain the analog character of the instrument, with the benefit of digital stability. DCOs were one of the key components that allowed Roland engineers to greatly reduce the price point of the Juno series, catering to a new market of synth lovers.

4. PORTAMENTO

The Juno-106 features a portamento function, the first synthesizer in its price range to do so. Portamento allows for sliding from one pitch to another. This function allows the Juno-106 to produce polyphonic portamento, and is a useful tool for both live performance and studio work. It was a relatively rare feature at the time of release and gave the Juno-106 a distinct edge that set it apart from its competitors. The portamento knob of the Juno-106 determines the time required to change pitches.

5. PATCH MEMORY STORAGE

The Juno-106 can store 128 memory patches. Patch memory allows for keyboard and front-panel control changes, patch storage, and other display information. Patch presets store portamento and modulation settings, as well as slider settings. The Juno-106 also features a battery backup circuit, to retain the programs even when the synthesizer is switched off. Patch editing can be used as a real time performance control. Patches can be stored to, or loaded from a standard cassette tape.

JUNO INSPIRED