Chapitre 0 : Prologue ; Avant Synth

The Yamaha Electone GX-1, an electronic organ employing a synth-style approach to tone generation, debuted in January 1975. Positioned as the new flagship of our Electone Series, this—the second Yamaha synthesizer—could be said to have been a “dream machine”. This was for good reason, and the GX-1 is assured of its place in the history of electronic musical instruments. As we will see later in Chapter 1, a prototype called the GX-707 was completed in 1973, but even before this, an elaborate story unfolded as Yamaha developers sought to achieve just such a dream machine, capable of the highest possible levels of musical expression. Many of the technologies that make today’s synthesizers a reality came into being much further back than most of us think, and in this chapter, we will look at how Yamaha poured everything into the development of successive Electones as the dawn of the true synthesizer approached.

The Legendary EX-21

It was 1959 when Yamaha—or Nippon Gakki as it was known at the time—introduced its first ever all-transistor electronic organ. This musical instrument, the D-1, was the very first Electone. New Electones were released practically every year over the next few years, and in the mid-sixties, president Genichi Kawakami called upon the company to draw on all of its technological skill and knowhow to create the world’s greatest electronic musical instrument. Four prototypes were built, ultimately leading to the development of the EX-21 in 1968, which was made public both at home in Japan and overseas the following year. This instrument in turn served as a proof of concept to illustrate the commercial potential of Yamaha's first Electone designed specifically for stage performance, the EX-42, which was scheduled for release later in 1969. In anticipation of its exhibition at the 1970 World Exposition in Osaka, however, the EX-21 was put through several additional rounds of development and testing. With single-block castings used for the instrument’s frame, pedals, and bench, several prototypes apparently cracked and broke before four could be built.

Tone generation in the EX-21 took the form of a hybrid system that combined the top octave and independent oscillator approaches. This system did not, however, fit inside the instrument itself and had to be housed in a separate, rack-like tone generator unit, connected by a special thick cable. The combined weight of the cast-metal body, which was prone to cracking, the tone generator unit, and tone cabinets was around 800 kg, meaning that the instrument could not easily be moved around. Nevertheless, a world tour of the EX-21 played by Koichi Oki and Yoshifumi Kirino got underway in May 1969 at a musical instrument show in Las Vegas. Audience members at each tour venue paid tribute to the instrument’s remarkable sound and expressive capabilities.

The world-tour player Yoshifumi Kirino had an EX-21 set up in his home for around two weeks. During that time, with the instrument itself in one room and the tone generator rack connected by cable in another, whenever he pressed one of the instrument’s registration buttons used for switching sound presets, he could hear a loud mechanical clashing noise coming from the tone generator. This was apparently caused by the action of relay switches, suggesting that EX-21 tones were changed mechanically. In terms of visual styling, however, Kirino said that the instrument looked like something incredibly futuristic from outer space.

Considering the design, weight, and tone-switching system, it is probably not surprising that the EX-21 had an almost astronomical price tag—roughly 20 million yen at the time, or around 100 million yen in today’s terms. Meanwhile, the model name came from adding an “X” to the identifier of the E-3, which was the best Electone on sale at that time, and then appending the number “21” in anticipation of the 21st century—then just over a few decades away. Incorporating absolutely all of the cutting-edge technologies and ideas of the late sixties, the EX-21 represented the pinnacle of the Electone family, and it would be only fair to call it the genesis of dream machines such as the GX-1.

The number of oscillators that a synthesizer has at its disposal for tone generation is intimately tied to the number of sounds that it can output simultaneously. On a four-note polyphonic instrument, for example, chords can be created by using each of the four oscillators to play different frequencies. Yet, early Yamaha Electones achieved full polyphony by allocating oscillator tones to any of the instrument’s keys as needed, and this was done by employing two different approaches—namely, the independent oscillator method and the top octave method.

As its name suggests, the independent oscillator method gives each key its own unique oscillator so that they can be played together to create harmonies. If you had a 40-key keyboard, therefore, you would need 40 independent oscillators. This can get very expensive very quickly, so the alternative top octave method requires only an octave’s worth of oscillators. Each one of these produces the corresponding note’s highest playable frequency, and cleverly utilizing the fact that pitch drops by exactly one octave when the frequency is halved, and the fundamental notes from the oscillators are converted into notes at lower octaves through simple integer division using a frequency divider circuit. Thus, with just twelve oscillators—one for each note in the chromatic scale—it is possible to simultaneously produce notes for every key on the keyboard.

Early Electones used constant oscillation for both methods. This means that every oscillator was always producing a tone when the instrument was turned on, but they were only sent to the amplifier as needed when the right key was pressed. This particular approach was, however, prone to sound leakage; sound would be output even when the instrument was not being played. An engineer would then need to step in to make adjustments.

In true dream-machine fashion, the EX-21 employed a hybrid system that combined both of these tone generation methods. In specific terms, it took the top octave system of our E-1 (640,000 yen, 1962) and integrated it with the independent oscillator system of our F-1 (2.2 million yen, 1964).

First Stage Model, the EX-42

The EX-21 was in essence succeeded by the EX-42, which was developed with a focus on release to the general public as opposed to prototype testing. To this end, tone generation was cut back to just top octave, helping to get the instrument weight down to 180 kg.

In terms of voices, the EX-42 was noteworthy for its nine tone levers ranging from 16 feet to 1 foot for organ flutes (also called pipe organs) in addition to other tone levers for voices such as brass and strings. It could also produce percussive tones and sounds with a decay stage like piano and harpsichord. Heralding functionality that would come later in full-fledged synths, a special tone called Wave Motion could be pitch shifted relative to other tones on the upper keyboard, and the result of combining these tones was a unique undulating sound. Certain tones were also touch responsive, and although limited in number, they provide clear evidence of the level of commitment of our developers. Additionally, the upper, lower, and foot keyboards were also equipped with tone levers called couplers that allowed voices created on one keyboard to be mixed with those of another, foreshadowing the layering feature of modern synthesizers.

The EX-42 had similar solo and portamento keyboards to the EX-21. The solo keyboard could be used to play a total of seven voices—four monophonic and three polyphonic. Players could mute the monophonic voices or apply vibrato by wiggling the keys left and right; meanwhile, solos with chords and harmonies could be played using the Chimes, Vibraphone, and Bell-Lyra polyphonic voices. Positioned to the left of the solo keyboard, the portamento keyboard was not unlike a ribbon controller capable of producing its own sound. It had six different voices, and the player could add expression in the form of sound effects and smooth pitch transitions. What’s more, it had an auto-mute mode and reverb, which was particularly effective for creating cosmic, other-worldly sounds. This portamento keyboard later reappeared in the GX-1 and the CS-80.

The EX-42 was the first Electone to come with auto-rhythm patterns—13 of them to be exact—and like all previous Electones, it had four percussion buttons. The instrument was also equipped with four buttons between the upper and lower keyboards for switching what would be called registration memories today. Each one of these buttons could be used to save and recall all upper, lower, and foot keyboard settings, and the player could also switch registrations by foot using any of four toe pistons that were, of course, linked to the registration buttons between the keyboards.

A pull-out preset board had, among other controllers, knobs that could be used to independently adjust the pitches of the solo, upper, lower, and foot keyboards. Naturally, they could be used to tune the keyboards to concert pitch, but these knobs could also shift the pitches of the keyboards very slightly relative to one another to create a distinctive pulsating audio effect.

Although top octave would ultimately be replaced by other tone-generation technologies, the sound creation abilities and expressivity of the EX-42 are so revolutionary it beggars belief that this instrument is now over 50 years old. It is no exaggeration to say that the GX-1 only existed because the EX-42 came first.

As a final thought on the EX-42, the following passage from an original may help shed some light on how Yamaha saw the instrument: “Composers and performers strive to lead the times and achieve distinctive forms of impression. Musical instruments naturally evolve in response, although the reverse can also be true. In either case, the birth of any instrument adds a new world of expression to the annals of music history, and the ambitious Yamaha Electone EX-42 is no exception. As a perfect integration of advanced electronic technologies and the world’s best musical craftsmanship, the EX-42 greatly expands the boundaries of both the musical instrument and artistic expression. It is fully capable of meeting the demands of composers and artists in a vast array of venues, such as large-scale concert halls, broadcast stations, restaurants, and recording studios. It is also a highly versatile partner in creating accompaniment music for TV shows, advertisement tracks, and electronic music. We are extremely proud of the new EX-42 and hope you too can appreciate its true potential.”

GX-1 Opens a Path to New Musical Expression

After completing work on the EX-21 and EX-42, Yamaha turned its attention to a new generation of Electones with the aim of achieving more natural sounds. One of these new instruments ultimately took form as the Electone GX-1.

A predecessor of this instrument, the GX-707 prototype was completed in 1973 and developed an excellent reputation thanks to demo performances at NAMM, Musikmesse, and various events in Japan. Further improvements to this prototype only hardened our conviction that the GX-1 needed to be released.

In marked contrast to earlier model Electones, which had used sustained, unchanging tones as the basis of sound creation, the GX-1 employed a technology called group-controlled voltage in line with our Living Sound design concept. Often called the polyphonic analog synthesizer approach, this made it possible for the instrument to produce sounds that changed over time.

More so than ever before, individual notes now shone brilliantly and chords resonated vibrantly. Gone were the tone levers of earlier Electones, replaced by preset voices with timbre changes and balance settings stored in advance on the instrument. The player would simply choose the best one to suit the music by pressing the corresponding tone selector in much the same way as we choose patches on today’s synths.

The GX-1 offered the following distinctive features not found on earlier Electones.

1. Analog synthesis used for tone generation

2. Up to 18 note polyphony, with eight each for the upper and lower keyboards, and one each for the solo and foot keyboards

3. Preset voices added using Tone Modules, and the ability to edit voices

4. Pitchbend, sustain, resonance, and reverb for greater levels of expressivity

5. Enhanced touch response

The GX-1 is classed as a synthesizer because its tone-generator section contains an analog synthesizer comprising VCOs, VCFs, and VCAs, and also because it can control changes in tone over time, which is fundamental to the creation of sounds. It is a little-known fact that this type of evolving sound could not easily be created using just the instrument, and the Tone Board—a dedicated editor incorporating a visual guide—was required to do this.

Meanwhile, two different types of Tone Modules containing presets were made available: the First Standard (or “black”) modules represented the initial lot, and the Second Standard (or “red”) modules were released later. You can see an actual GX-1 for yourself at Innovation Road—the Yamaha musical instrument museum that we opened in 2018. Although the instrument normally came with a fixed bench, our display model has a powered one that can be adjusted back and forth and side to side. This limited-edition model was made at the request of company president Kawakami for use in Electone competitions and at music schools all over Japan, and the powered bench ensured that children as well as adults could play it without difficulty.

The EX-1 and EX-2 Electones and Their PASS Tone Generators

Designed for stage performances, the GX-1 had been endowed with a considerably large analog-synthesizer system which, from the perspective of size as well as cost, was clearly not suited to instruments intended for homes and studios. Accordingly, development of a new tone generator that leveraged the benefits of fast-evolving digital technologies without compromising sound quality and expressivity proceeded at high speed in parallel with our work on the GX-1. The resulting Pulse Analog Synthesis System (PASS) was an analog-digital hybrid first used in the EX-1 and EX-2 of 1977. Staying true to the Living Sound design concept that had been so successful in the GX-1, PASS achieved rich, luscious sounds using a pair of tone generators—specifically, a flute tone (or “organ sound”) generator and an orchestra tone generator, which could produce violin, piano, and other sounds that change over time. These two tone generators could also be layered on top of one another for sound creation, and the ability of the EX Electones to shift the octave of the orchestral voices provided for even more flexibility and creativity in sound sculpting. Furthermore, a celeste effect could layer two flute voices or two orchestral voices to produce richer, deeper sounds. What’s more, the EX-1 and EX-2 were also equipped with filters—a key part of any serious synthesizer—allowing users to take a synth-like approach to sound creation.

All of this was made possible by new chips that we developed specifically for tone generators. Thanks to this innovation, Yamaha could now produce instruments that were more compact, offered greater functionality, and were cheaper to manufacture than ever before. The resulting PASS tone generators were mainly used for Electones, notably the new C Series of 1978 that sold more than any other model in the history of these instruments.

As we will see in Chapter 2, development of FM tone generators had already begun at this time. From 1981 onward, these digital tone generators would rapidly become our mainstay, meaning that PASS was relatively short-lived. That said, this approach to tone generation did cross over to Yamaha synths, where it was used in our SK Series instruments of 1979 through 1981. These as well as the GS-1 and CE Series also featured Ensemble and Symphonic effects—more specifically, three-phase choruses using a BBD analog delay circuit—which were indispensable in the PASS era.

From the earliest days of the company, Yamaha developers never forgot about the player and polyphony as they worked on new musical instruments. Thanks to this commitment, the technology of the sixties lives on in the instruments of today in the form not only of tone generators, but also mechanical keyboards that feel and respond like the real thing, ribbon controllers that provide for much greater expression, and preset memory. The world would have to wait until the SY-1 of 1974 for a full-on Yamaha analog synth; however, from the perspective of performance and technology (other than tones that change in timbre over time), we were already in that decade exploring application of the synthesizer in ways that went beyond the reproduction of existing instrument sounds to achieve their own unique expression in sound. Against this backdrop, we owe those early developers a huge debt of gratitude for their curiosity and tenacity.

From top octave through to AWM, the first instruments to feature the latest tone generation technologies were all Electone models (regardless of whether or not they were able to shape their own sounds).