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Chapter8   "This Will Replace the LP Record"

" This Will Replace the LP Record "

Around the same time, Ohga received a telex from L.F. Ottens, a Philips technical executive. The message on the telex said, "If you happen to come to Europe, please visit us." Ohga had known Ottens since the mid-1960s, when Sony and Philips had successfully achieved the global standardization of the audio compact cassette. Since then, a strong relationship based on trust had developed between the executives of Sony and Philips (see Part II, Chapter 5).

In June 1978, when Ohga had the opportunity to visit the Philips head office in Eindhoven, Ottens showed him an Audio Long-Playing (ALP) disc similar to the one which Nakajima and Doi had been working on. Philips was the manufacturer that had pioneered the optical videodisc system using laser technology in the 1970s. The ALP was a by-product of this technology. During the 1970s, various manufacturers had been competing to develop a digital audio disc. "This 11.5 cm disc has a playing time of one hour," Ottens explained while giving a demonstration. To Ohga's eye, the disc appeared to be very small. Technologically speaking, it was something that Sony could also manufacture. If a 30 cm disc could yield thirteen hours and twenty minutes of playing time, a 9 cm disc would theoretically yield an hour's playing time. Philips had been trying to develop a one-hour disc that could fit into an automobile dashboard. Ohga recognized the value and marketability of the product. Philips believed that this disc, which produced high quality digital sound and was small and easy to handle, would completely replace LP records.
Ottens had invited Ohga to get a sense of whether Sony was interested in jointly developing and marketing the new 11.5 cm audio digital disc with Philips. Originally, the development of the audio digital disc in Sony was born from Nakajima's passion for high quality digital sound. Nakajima had dedicated himself to the task of developing such a disc. But could this product really be marketed? People still placed great trust in vinyl LP records.

Ohga's decision was quick. He felt that the small, shiny silver disc that he saw at Philips had great potential. He believed it would replace the LP record. The disc still recorded too much background noise and the development of a signal error correction system was at its very early stage. Nevertheless, Ohga felt that Sony and Philips could create a good product together. Philips was a world leader in optical videodiscs, and Sony had considerable expertise in digital audio signal processing technology. If Sony and Philips worked together, it was likely that they could produce an ideal recording medium. Moreover, both companies owned software record companies-Philips had world famous record company Polygram, while Sony had CBS/Sony Records, which was established in 1968 and had grown considerably since then. Polygram and CBS/Sony could therefore supply software for Philips and Sony. At that time, Ohga was an executive deputy president of Sony Corporation and the president of CBS/Sony.

While the new Sony-Philips partnership was being cemented, executives from both companies visited one another. During one of these visits, Morita, who was Chairman at the time, and Iwama, who was President, formally expressed their agreement for the joint development, in order to propose the result of their development to the DAD (Digital Audio Disc) Conference. The DAD Conference comprised of 29 manufacturers from around the world who had started talks toward the standardization of the digital audio disc in September 1977.

Chasing and Being Chased


  • Members of the Sony and Philips research teams, including Nakajima (front row, second from right), Miyaoka (back row, third from left), and Doi (back row, fourth from right).
In late August 1979, joint development between Sony and Philips got under way. In 1966, both companies had signed a free cross-licensing contract for video tape recorders. Following the start of development on the digital audio disc, the companies renegotiated the original contract to cover a wide range of matters, which included discs.

Meetings were held every few months in Tokyo and Eindhoven where research findings were exchanged and discussed. Members of Sony's Audio Technology Center, including Nakajima, Doi, Hiroshi Ogawa, Shunsuke Furukawa, and Kentaro Kodaka attended the meetings. Other participants included Miyaoka and Yosuke Naruse of the Disc Development Division and Akihiro Mizushima of the Technology Planning Department. Discussions began rather calmly, with the comment, "Let's start by deciding on how to record a signal." Substantive discussions began soon after, as the researchers became inspired by each other's abundant enthusiasm.

One topic that caused considerable debate was the issue of the number of quantization bits, which determines the accuracy of quantization. From the beginning, Philips argued for 14 bits, whereas Doi who represented Sony favored 16 bits. Achieving a higher number of quantization bits became more difficult and expensive. Doi believed that it was worth trying to produce a 16-bit system that would last well into the 21st century. When Philips researchers asked, "Will a 11.5 cm disc with sixty minutes of recording time be okay?" Sony researchers said, "No, we want a 12 cm disc with seventy-five minutes of recording time."

Each argument was valid. Philips argued for a 11.5 cm disc because this was the same length as the diagonal length of an audiocassette. Also, this size satisfied the DIN standard and thus would be the right size for a car audio system in the European market. But it was Ohga, a trained musician, who decisively presented Sony's argument for a 12 cm, seventy-five minute disc. He argued that, "Just as a curtain is never lowered halfway through an opera, a disc should be large enough to hold all of Beethoven's Ninth Symphony." Ohga believed that the disc needed to be of a practical size for music aficionados and that 95% of all classical music pieces would fit onto a seventy-five minute disc. Therefore, a 12 cm disc was necessary to guarantee seventy-five minutes of playing time.

After hearing Ohga's argument, researchers at Philips said, "A 12 cm disc won't fit into a suit jacket pocket." "Well, let's see if it does or not," replied the Sony researchers. They measured the top pockets of a Japanese, an American and European suit jackets. The results showed that "There's no suit jacket with a top pocket size less than 14 cm wide. A 12 cm disc will be fine." It was decided that the maximum playing time would be seventy-five minutes (seventy-four minutes and forty-two seconds to be exact) and the diameter of the disc would be 12 cm. Philips also agreed to Sony's proposals for a 44.1kHz sampling frequency and 16 bits.
The next topic was error correction, and it was now Doi's turn to handle matters. Since making the first digital audio disc, he continued to develop digital technology. The Sony researchers visited Eindhoven to study Philips disc technology. Philips' researchers visited Sony, learning what they could about digital signal processing and signal error correction. The capabilities of both research teams grew, as they competed and cooperated with each other. Their relationship was a partnership to establish disc standards. At the same time, they were rivals.

Ibuka, who opposed the move to digital audio in the beginning, had changed his stance. Instead of saying, "Forget digital audio," he started saying, "Let's make this work."

" Our Contributions Are Equal "


  • The 12-cm digital audio disc jointly developed by Sony and Philips, which replaced the analog LP (foreground).
Sony and Philips exchanged opinions and debated on a range of issues in their quest to create a disc with the aim of establishing standards by April 1980 for the DAD Conference in June. Serious discussion between Sony and Philips continued. With the digital audio disc gradually taking shape, technical specifications were nearing completion. Engineers on both sides, however, remained uncompromising. "If we think this out a little more, we can improve this part slightly," they said. "I think this is a slightly better proposal than that one," they added. The standards were not completed by the initial target date. With the June deadline approaching, they had to end discussions and finalize standards for the conference.

Prior to presenting the proposal at the conference, Nakajima and the Philips representative, P.W. Böels, spoke privately. They agreed to avoid such comments as, "We developed this part and that part" and to emphasize that the disc's development was a joint effort by saying, "Our contributions are equal." They speculated that surely some of the engineers would not like this. For an engineer, to claim credit and gain recognition is a strong motivating force. As an engineer himself, Nakajima could understand this feeling. Somehow, Nakajima and Böels convinced the engineers to put their companies before individual achievements and to get ready to finalize the standards before the DAD Conference. The name they proposed for the system was Compact Disc Digital Audio System.

At the DAD Conference, three newly developed systems were assessed. These were the optical disc system proposed by Sony and Philips, a mechanical system proposed by Telefunken, and an electrostatic system proposed by JVC. There was a major difference between the optical system and those proposed by the two other companies. In the Sony-Philips system, a smooth layer of plastic protected audio signals recorded as a series of bits along the disc. The disc's surface was entirely free of grooves. As the system's pickup device was operated using optical technology, it could read the recordings below the protected surface without coming in contact with the disc. As a result, the system did not have the kind of problems that arise from contact between the pickup device and the recording medium, contributing to an extremely long-playing life. Despite a small amount of static, the system had good quality sound reproduction, comparable to a live performance. "If we are going to make this disc the next generation LP, it has to be easy to handle," said the Sony engineers. The other two systems read the signal through direct contact with the surface of the disc.

In April 1981, the DAD Conference avoided officially approving just one system. The Conference decided to recognize both the Sony-Philips system and the one developed by JVC.

X Day in October 1982


  • The CD prototype, nicknamed " Goronta," used just three small LSI circuits.
While preparing for the DAD Conference, the Sony team was also engaged in the commercialization of the first CD system, which Ohga decided to launch in October 1982. Members of the Audio Technology Center, the Audio Business Group, including the Engineering Development Department led by Katsuaki Tsurushima, and the Audio Division led by Nobuyuki Idei, were all involved in commercializing the CD system. However, meeting this deadline was going to be tough. Sony and Philips had worked together diligently for a year to improve their technologies and build a product based on the standards they had established. But the product could not yet be commercialized, partly due to a lack of key components needed to manufacture the hardware. The situation was such that the engineers were always complaining: "We don't have this component part" or "We don't have that one."

To exacerbate the shortage of parts, the pickup device used to read the signal on the disc, essentially the heart of the CD system, was inadequate. Important parts for the device are the laser diode, which produces the light beam for reading the disc; the objective lens, which projects light from the laser onto the disc; and the dual-axis device that moves the lens and guides the light in unison over the spinning disc. These parts were not satisfactory. The engineers had to direct the light beam so it could pick up bits 0.5 micrometers wide lined up in a space of 1.6 micrometers wide, the equivalent to one-fortieth or fiftieth the thickness of a strand of hair. On a 12 cm disc there are roughly two billion bits. None of the parts that had been used thus far in the video disc player was adequate for the task. The helium neon gas laser used with the video disc was 20 cm longer and thus far too big to be used with a new 12 cm disc system. The Sony team could have reduced the size of the laser by using semiconductors. However, laser technology using semiconductors was still in the experimental stage.

The lens had to be as minute as a microscope lens meaning that a compound lens consisting of several glass lenses just a few millimeters in diameter stacked together had to be made to move as a single unit. It was a difficult task to position the axis, along which the optical pickup moves, so that the pickup light aligns exactly with the bits it was reading. In addition, the surface of the lens had to be polished so that it was less than 0.2 micrometers thick.

There were also problems with using semiconductors. To carry out advanced digital signal processing, previously done by using 500 ICs, it was necessary to develop an LSI circuit. If one could not be created, the system could not be made into a compact player that could be enjoyed by the average consumer. The AD/DA (Analog-Digital to Digital-Analog) converter, which processes and converts an analog signal to a digital one and vice versa, were plagued with problems. They seriously considered if it was really possible to commercialize the system in just two years?

When the engineers listed the things that still had to be done and the problems they faced, there were over two hundred items. The team visited different laser manufacturers to examine various lasers. They found a high quality laser manufactured by Sharp that fortunately could be mass-produced. They decided for the optical pickup device. A dual-axis device named Tsurusu, after Tsurushima, was developed to ensure that the light of the optical pickup exactly followed the bits on the spinning disc.

The optical pickup device ultimately developed by Sony's Optical Device Division was smaller than comparable devices. The Sony device picked up every microscopic bit on the disc. The efforts of the Semiconductor Group were also outstanding. The DA converter, which until that time had cost nearly 300,000 yen to produce due to parts, was made by using just one IC, cutting the cost to approximately 10,000 yen. This device reduced the size of the player considerably, contributing to cost reduction. In addition, the group successfully miniaturized the 500 ICs used for signal processing, condensing them into three small LSI circuits.

At the 1981 Audio Fair, Sony exhibited a much-improved CD system prototype. Just a few days earlier, a set of three LSI circuits used in place of the 500 ICs had been realized. The prototype held the disc so it appeared to stand sideways, sparkling brightly as it spun on the front face of the player. Standing the disc on its side was technically very difficult. Despite the claims of the engineers that they had succeeded in doing this, the prototype looked a little awkward, thus given the nickname "Goronta," which was derived from the Japanese onomatopoetic word goron, meaning bulky and awkward.
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