History of Speaker

History of Speaker - Since 1967

The History of Natural Sound Speakers (Since 1967)

Having interrupted the launch of new HiFi products from the late 1950s to the 1960s in order to focus its development resources on the revolutionary new Electone electronic organ, in 1967 Yamaha began its history as a HiFi speaker manufacturer by repurposing and improving the Electone’s NS (Natural Sound) Speaker for HiFi audio use. Released in 1974 and featuring the world’s first pure beryllium diaphragm, the NS-1000/1000M won worldwide acclaim for its clear and open sound, and after that models such as the NS-451 and NS-10M, producing good quality sound at a reasonable price thanks to the unique sheet method of manufacturing. Not to mention the AST-1, which employed active servo technology to expand speaker limits by actively controlling air vibrations and built confidence in the overall strength of Yamaha’s ingenious approach to sound.


Inspired by musical instrument making, this was the first large speaker unit to bring the world the natural sound it was asking for.



Released in 1967, the NS-20 and NS-30 were Yamaha’s historic first Natural Sound speakers. Both featured an irregular three-way configuration based on the JA-6002 (an 89x63cm diaphragm used in the NS-30) and JA-5002 (the 68x50cm version used in the NS-20) units originally developed by Yamaha for the Electone and improved for HiFi audio use. Each was configured the same way apart from the size of the unit and cabinet. The cabinet sizes were determined based on the large dimensions of the NS-30’s JA-6002 unit and the NS-20’s JA-5002 unit, their single-unit measurements of 1030mm high x 740mm wide x 315mm deep and 860mm high x 620mm wide x 310mm deep being standard for the large studio monitors of the time. To put it simply, the NS-30 had a baffle size comparable to the JBL4343 and the NS-20 had a baffle size comparable to the Diatone 2S-305. With a unique Styrofoam diaphragm, this unit bore the name Natural Sound Speaker (NS Speaker) and was the origin of the "natural sound" slogan Yamaha has continued to use ever since.

The front of the NS speaker mounted fully on the rear side of the cabinet (the back of the unit) was also substantially open state, full range driven, and by mounting the two-way consisting of a 30cm (NS-30) or 20cm (NS-20) "squawker" and 5cm tweeter on the front side it had the configuration of a sound field type speaker, actively taking advantage of the effects of reflected sound. For that reason, to borrow a phrase from the documentation of the day, like an upright piano it was recommended that the NS speaker be placed away from the wall behind it. Interestingly, the documentation of the time used different values for a recommended distance from the wall, the domestic Japanese documentation suggesting "5 to 10cm" and the overseas documentation "6 inches" (around 15cm). From this we can guess that there was a business judgment at the time that 15cm would be a tough sell for small Japanese rooms. Actual sales in North America and elsewhere achieved a respectable level, but it faced difficulty in the domestic market due to its size and installation requirements.

Creating a major sensation for their all-time originality, the NS speaker lineup later expanded to include the smaller JA-5004 (58x46cm diaphragm), JA-3501 (51x38cm) and JA-3502 (45x32cm) units along with a modular stereo set and wall mountable compact speakers. For five years it served as the face of Yamaha speakers until the 1973 release of the NS-570, which became the recommended speaker for the first run of Yamaha HiFi components, the 700 series. After 1974, the NS-600 and NS-1000M series of general use round speakers were big hits and the NS speaker disappeared from the product lineup, but the idea of considering room acoustics in playback like a musical instrument manufacturer soon led to the creation of the world’s first Digital Sound Field Processor, the DSP-1, in 1986 and on to a home theater product series.



Won countless fans with its natural and delicate "European sound" and beautiful plain wood cabinet.



In the fall of 1972, Yamaha introduced the NS-620/NS-630/NS-650 intermediate diffusion bookshelf speakers, the first part of its new all-round unit NS-600 Series. The following spring in 1973, the advanced NS-670 and NS-690 units appeared, completing the transition from the ingenious NS Speaker to a conventional round unit. Even in the NS-600 series, the three lower models that appeared in 1972 dropped the walnut finish baffle unit for an orthodox external design, while the two higher models that appeared in 1973 took on the same castor open pore finish as the next-generation HiFi components released in the same period. Its redesign featured a modern-looking three-sided enclosure structure that did not show a cross-section of the side plate.

Except for the NS-670 woofer, which used the JA-2501A, an improved model for the NS-650, the NS-690 and NS-670 speaker units were completely redesigned, establishing the technologies that became standard in Yamaha speakers like a large ferrite magnet and copper ribbon wire edgewise-wound voice coil woofer, a tangential edge molded soft dome midrange with a back cavity packed with sound absorbing material to lower the FO (lowest resonance frequency), and a soft dome tweeter integrating the voice coil bobbin and diaphragm.

The midrange and tweeter were made of an original double-coated material made up of a base of thermoplastic resin on fabric serving mainly to maintain the shape and viscoelastic rubber-based resin acting primarily to dampen resonance. As well as becoming the standard for later Yamaha soft dome units, it was also used in elements such as the NS-1000M woofer edge. An aluminum diecast frame made using Yamaha’s alloy technology was adopted in all units, and its metallic feel combined with a mechanical structure was highlighted in comparison with the natural texture of the wooden exterior design to give the Yamaha speaker what could be called an all-new identity. In combination with the CA-1000 Integrated Amplifier on sale at the same time, the delicate, natural tone of the NS-690 made it a smash hit for its "European sound" unavailable in conventional domestic systems. It shared its popularity with the NS-1000M, which was introduced the following year.



The world’s first pure beryllium diaphragm in a masterpiece professional monitor that gained Yamaha much respect.



The first speaker system to make use of Yamaha’s pure beryllium diaphragm, as legendary as our SIT (vertical power FET) HiFi technology, the NS-1000/NS-1000M was released in 1974. Lightweight with high rigidity and hardness and a sound propagation velocity more than twice that of titanium and magnesium, from early days beryllium had drawn attention as an ideal diaphragm material. Its brittleness, however, made it difficult to work with, and its susceptibility to corrosion meant that up to then it had never been put into practical application. By utilizing the electron beam vacuum deposition method used in state-of-the-art LSI manufacturing and a special alloy technology developed since its piano frame building days, Yamaha developed a unique deposition molding manufacturing process that produced a diaphragm of 99.99% pure beryllium plasma, for the first time in the world bringing a pure beryllium diaphragm to the commercial marketplace.

The NS-1000/1000M featured the first units to use this pure beryllium diaphragm, the JA-0801 8.8cm midrange and JA-0513 3.3cm tweeter, and along with the JA-3058 (NS-1000)/JA-3058A (NS-1000M) 30cm woofer developed especially for this product it formed a 3-way bookshelf model with precise tone over a wide frequency range, sparkling clarity in the middle and high ranges that won it acclaim around the world as soon as it was released. Notably, it unanimously earned the highest rating in Western audio magazines that up until then had largely ignored Japanese-made speakers, becoming the first luxury speakers made in Japan to become a worldwide hit. Two years after it hit the market, in 1976, the Swedish state-owned broadcasting corporation chose the NS-1000M as its official monitor speaker, and with orders for 1000 units it surpassed prestigious European manufacturers Tandberg, Celestion, Bang & Olufsen and Bowers & Wilkins. Moreover, in 1978 the Finland national broadcaster ordered 200 units of the NS-1000M, cementing its firm position as a professional monitor speaker.

Positioned as a high-end unit for home use and priced at 145,000 yen at the time of its release, the NS-1000 featured an ebony luxury urethane paint finish exterior, while the NS-1000M, priced at 108,000 yen and aimed at use from the home to the studio, sported a birch semi-gloss black paint finish. With a somewhat large thick-walled cabinet and removable saran net, the NS-1000 weighed in at 39kg, 8kg heavier than the 31kg NS-1000M. As is evident from the difference in price, the cabinet finish of the NS-1000 was lavish enough to rival that of a luxury wood grain piano, but the fearless black design and overwhelming cost-performance of the NS-1000M made it the focus of popular attention. The upgraded NS-2000 released in 1982 and the NS-1000X released in 1986 reinforced the reputation of the original machine, and in the 23 years until the end of all beryllium diaphragm unit production in 1997 it was a long-lasting hit with more than 200,000 units sold.



With its revolutionary sheet process, the white cone redefined the sound quality of the entry-level speaker.



The NS-451 targeted the younger crowd who had never been a major demographic for conventional Yamaha speakers, an introductory-class 20cm two-way bass reflex system that produced energetic sound with attractive bass at a reasonable price. Its main feature, the Strong Woofer white woofer unit, was an important key to achieving high cost-performance. To put it simply, the sheet process involved shaping a round paperboard sheet cut out into a cone instead of the conventional process of molding paper directly into a 3D cone shape. The catalogs of the time extolled the merits of the process, saying, "fewer irregularities in thickness and density" and "extremely strong despite being lightweight," but naturally, paper is supposed to be uniform and homogeneous, and it goes without saying that this would be the result of cutting such material into a round shape.

Producing a stable supply of relatively large diameter, high efficiency yet low cost paper cone speakers while still maintaining sound tuning flexibility was a game changing, outside the box idea. With its low price of 26,500 yen making a full component system possible for 100,00 yen, the NS-451 became Yamaha’s unique gateway for young fans to get the most out of their music, and the concept of the white woofer produced by the sheet process was incorporated into Yamaha’s worldwide best-selling NS-10M and many other of its HiFi and theater speakers. The problem with sheet process speakers was that the seam where the cone element was attached was visible, but thanks to the pure white color it wasn’t noticeable and didn’t look strange or questionable. The dazzling white diaphragm of the sheet process speaker was probably due as much to this as to the desire to take advantage of the basic color of the paper and to make products that looked distinctive.



The original 10M that launched a boom, built without compromise for powerful sound exceeding its size and a playful spirit.



One of Yamaha’s masterpieces alongside the NS-1000M, with more than 300,000 units in the series sold making it one of the world’s most famous speakers. Synonymous today with small studio monitors, the NS-10M was originally intended as something else, a follow-up to the youth-oriented, low cost HiFi NS-451 speaker of 1976.

The NS-1000M had already gained a worldwide reputation and now the new sealed cabinet NS-10M appeared with a playful but realistic sound, the image of its seven-step black painted real birch wood finish, three-way enclosure structure and symmetrical left-right arrangement becoming the emblem of the NS-10M as much as the NS-1000M’s. Unusually for the time it was sold in sets of two, and with an easy to understand price of 50,000 yen per set and a fashionable packaging box designed to make it easy to carry home by hand, everything about it was epoch-making. It was nearly twice as compact as the NS-451 and rival products in the same class, with a price proportional to its size, but it was a bit risky to release it into the popular price range of the day because of the compact size. However, the combined benefits of a sound beyond what you would expect from its size and concept, a sound that made conventional large speakers seem outdated, and a small size that meant unlimited choices for speaker placement, sparked a boom big enough to be called a singular phenomenon.

Its woofer unit was the same sheet process white cone used in the NS-451 in a new slightly smaller 18cm design with the magnet changed from aluminum-nickel to ferrite and a sealed cabinet. Its 3.5cm tangential edge molded soft dome tweeter shared the basic design of the NS-690II and, completely abolishing the seldom-used level control, its high purity sound quality was enough to make even sound maniacs sigh. The NS-10M’s rarely heard ability to skillfully pick up music’s essence made it popular even among professional sound engineers and musicians, spreading widely to become an essential tool at the forefront of the world’s music production and recording studios.



Loaded with high technology, a superior floor speaker that led the way among the world’s studio monitors.



With the beryllium diaphragm and other elements that contributed to the success of the NS-1000M, would the creation of full-size floor speakers making complete use of Yamaha’s world-renowned state-of-the-art technology really mean that any sound could be reproduced? The FX-1 high-grade floor speaker released in 1978 bore the weight of just such speculation and pure curiosity from developers and Japanese audiophiles alike. At the beginning of its catalog was this paragraph:

To speak honestly about the way sound should be, you may think differently, but when it comes to the totality of sound we believe that this is one of the highest peaks. We think that what JBL and Altec are doing is good, but like a volcano we seek to build a higher and higher new peak with each new eruption.

At the time, the presence of floor studio monitor speakers like those made by JBL and Altec was a given, and the dream of equaling or even surpassing them was the dream of not just Yamaha but of every Japanese speaker manufacturer. The three-way horn midrange/tweeter and 38cm woofer configuration, aluminum-nickel magnetic circuit and cabinet proportions of the FX-1 were very similar to JBL’s latest studio monitor, the 4333A, a unit which won the praise of the high-end audiophiles of the day. In each unit, from the corrugated non-pressed paper cone woofers and rear loading horn midrange with slanted plate acoustic lens to the ring diaphragm horn tweeter, it was obvious that every detail had been developed with strong awareness of JBL’s professional products.

However, it’s an over simplification to conclude that the FX-1 was just a JBL imitation. While operating among the constraints of the best studio monitors at the very peak of all speakers, the design team sought to determine whether Yamaha’s materials and manufacturing techniques were really valid while paying the utmost respect to a style that had been polished and refined over a long span of time. To achieve that goal, it was no doubt the design team’s intention to line itself up perfectly against JBL. Too precisely a luxury unit to see much use as professional equipment, the FX-1 never surpassed JBL or Altec in sales, but thanks to its legendary expressive power that brought the density of the NS-1000M to the greatly expanded scale of the large floor monitor, the FX-1 name still lives on in the memory of countless listeners.



The ultimate version of the NS-690 series, featuring a 100% grand piano soundboard-grade spruce woofer.



Released in 1980, the NS-690III was the final model in the NS-690 series which had been a long-selling hit since 1973. HiFi components that had debuted with plain wood (castor) cabinets at the same time as the original NS-690 had already undergone a generational change, with the unit exterior changing from castor to an American walnut open pore finish to match the same-generation amplifiers and players. From the plywood cabinet with particleboard back plate used in the original NS-690, the second generation NS-690II changed to an entirely particleboard construction, increasing in weight to 27kg from the original’s 22kg. In appearance there was little change in the basic design of the midrange and tweeter, which used a tangential edge molded soft dome, but the coating material, critical to sound production, was altered to further improve linearity.

But the most important thing about this unit was the world’s first woofer diaphragm made of Yamaha’s proprietary 100% spruce pulp. Made with carefully selected straight grain portions of Yamaha grand piano soundboard-grade spruce for superior tone and sound quality, the raw pulp materials were specially refined for producing the cone paper, keeping the delicate sound that had been described as "European elegance" while producing both deep bass tone and clear resolution.

Without compromising the character of the original, it goes without saying that the aging NS-690III boasted the highest degree of sound quality perfection in its series, but in an audio world shaken by the dawn of the CD in the early 1980’s, a world where analog had become an epithet, its image lost some of its luster and it can’t be denied that it began to look out of date. It wasn’t until the release of the NS-1 classics in 1988 that speakers that could handle the spread of the CD and legitimately be called successors to the line appeared.



Permeated by the Yamaha way, this large floor speaker added rich bass to the clarity of pure beryllium.



Following 1978’s FX-1 beryllium unit floor speaker, this was the second edition in the FX Series. While the FX-1 lavishly featured what has to be called unprecedented aluminum-nickel magnet beryllium horn systems in both the midrange and tweeter, the FX-3 was equipped with the JA0802 8.8cm beryllium dome midrange and JA0526 3.3cm beryllium dome tweeter refined from the NS-1000M. The FX-1 also featured a 38cm diameter interior magnet woofer with a giant aluminum-nickel magnet to match the midrange and tweeter, while the FX-3 used a 36cm woofer with exterior general ferrite magnet. Apart from both being large floor-type systems and both featuring the same diaphragm material there was little in common between the two models’ concepts, and their price ranks were completely different, the FX-1 retailing at 585,000 yen per unit and the FX-3 for 220,000 yen.

Unlike the FX-1, which was intended as a competitor for the best overseas studio monitors without concern for profitability, the FX-3 was simply a variation on the NS-1000M. The FX-3 was a relatively inconspicuous presence at the peak of the Japanese bookshelf market, but it enjoyed popularity in North America and other places with a mainstream floor unit market as a model that let you enjoy the large-scale, rich bass beryllium performance of the NS-1000M. Of course in Japan as well, the cost-performance of the FX-3 certainly stood out compared to the typical import speakers you could buy for around 200,000 yen at the time, and the Japanese catalog specifically mentioned JBL and Tannoy in recommending the FX-3 as an alternative to imported high-end floor speakers.



The peak version of the NS-1000M, incorporating the trends of the ‘80s like pure carbon fiber cone woofers.



In tandem with the 1982 introduction of the first digital audio media geared to the consumer, the CD, the competition in the speaker world to develop new materials to replace the paper cone became increasingly prominent. Part of the competition between companies centered on carbon-based materials with physical properties suitable for speaker use. Having consistently stuck with the paper cone ever since the NS-600 series, in the fall of 1982 just before the birth of the CD, Yamaha finally announced the release of the pure carbon fiber cone, made of 100% carbon materials without using paper, in the new NS-2000. As is evident from the model number, the NS-2000 was developed as a high-end model directly from the NS-1000M which had occupied the position of the face of Yamaha speakers for the eight years since 1974. Naturally, to serve as a higher grade version of a unit that already had a solid reputation like the NS-1000M many of its existing elements had to be refined, and to form the center of that technology Yamaha developed its first 33cm diameter pure carbon fiber woofer, the JA3301, from scratch.

The major concept behind this pure fiber cone was to take full advantage of carbon’s inherent rigidity and elasticity by preserving its long fibers in creating the diaphragm. Specifically, a carbon sheet with its fibers aligned in one direction was cut into eight equal parts with the eight resulting segments arranged in a circle so that when joined they would form a cone with all fibers projecting in a radial direction. This allowed the creation of a cone made from 100% pure carbon, apart from the adhesive used to join it together.

You would need a rational reason for the tried-and-true paper cone to be discarded in favor of the chic new carbon style, and the development team probably had devised such an elaborate process in order to use carbon fiber, with a sound transmission rate and elasticity second only to the beryllium used in midrange and tweeters, in complete purity. Developed for the FX-3, the JA0802A and JA0526A midrange and tweeter adopted the pure beryllium dome. Here too there was success in further enhancing the sound’s expressive power by the deposition of even finer beryllium particles. Strongly advocating the position that audio equipment must be inherently musical and human while also incorporating the trends of the ‘80s, the NS-2000 was a milestone produced by eight years of evolution from the achievements of the NS-1000M, and has to be considered a success even if its direction was somewhat different.



A 31cm three-way bookshelf strategic model employed on the front lines of the popular price range war.



In a late 1980s Japanese audio market that had regained momentum thanks to the spread of the CD and a booming economy, the popular price range war took place. One manufacturer after another introduced speaker models strategically priced at around 59,800 yen and integrated amplifiers at around 79,800 yen, with the media throwing additional fuel on the fire.

Speaking of speakers, since all the large three-way bookshelf models seemed to have the same personality, consumers were focused entirely on luxury and slight differences in specifications, in particular mass. A 30cm-plus woofer diameter and a mass of at least 25kg formed the lower limit of the popular price speaker, with manufacturers churning out models incorporating various heavy materials into cabinets that approached 35kg and woofer diameters creeping upward in 1cm increments from 30cm to 31cm to 32cm to avoid losing out to competitors.

Released in 1986, Yamaha’s NS-700X charged straight to the forefront of the popular price speaker class, its major selling point being its dome tweeter’s ion plated amorphous diamond diaphragm that achieved a hardness comparable to that of diamond. This diaphragm was touted as taking advantage of Yamaha’s unique LSI manufacturing technology, with catalogs saying, "The use of a high voltage ion acceleration gun to embed carbon atoms on the surface of the titanium that forms the diaphragm base allows the generation of an amorphous layer of high hardness," and with the same material used in the cone midrange’s center cap it was solidly aimed at high-fidelity playback from digital sources. The woofer utilized a high rigidity twin pure carbon cloth cone featuring two sheets of woven carbon cloth fixed at a 45 degree angle relative to each other. With a diameter of 31cm, its twelve fixing bolts were rarely seen in high-grade machines and certainly caught the eye. While meeting the requirements of a popular price speaker, the NS-700X gained a reputation for producing high-quality sound. But after just this model Yamaha withdrew from the popular price front lines and soon introduced to the world a new speaker completely opposed to the doctrine of "quantity."



With improved usability as a professional monitor, nothing else changed in this second generation 10M.



Having remained unchanged since 1978 as it set records as a long-seller, after ten years the NS-10M underwent its first redesign in 1987. There were only three substantial changes along with its unit class and a luxurious seven-coat paint process real wood cabinet, so the model change did not impact any of its essential characteristics. The price increased by 5,000 yen, but it can be said in good conscience that the price had to match the improvements in the unit’s basic specifications.

Part of the redesign was the addition of 5mm thickness felt ring acoustic absorbers around the tweeters for sound absorption. As also mentioned in the catalog, as the use of the NS-10M in its original function as a studio monitor spread, some users began to point out the strength of its treble, and especially as we entered the digital age the technique of covering the front of the tweeter with one sheet of tissue became common among studio engineers. Tuning with the use of felt eliminated the need for this practice. The second change was to replace the simple push-type speaker cable terminal with a screw-on type that made it difficult for the cable to come free. The third was to increase the input resistance. Examination of the specifications of each unit reveals that they were the same as before the redesign, meaning that it should be considered that most of the input resistance was due to the numerical values of the allowable input having been described in expectation of a margin and that they had been revised to appropriate values with an eye toward product planning.

If you compare more closely, you will also notice that each unit’s attachment screws had been changed to a hex bolt, meaning it was easier to disconnect and exchange them. As part of this 1987 renewal, three models, the horizontally arranged NS-10M PRO (front and back character displays with the unit attached laterally at 90 degrees), the NS-10M Studio which omitted the grille net feature, and the NS-10MC which included bolt holes for ceiling mounting the NS-10M Studio and a grille net, were added to the lineup as business models.



Using CG beryllium to eliminate transmission loss in large crystallization, this was the 10000 Series’ best bookshelf unit.



The NSX-10000 was released in 1987 with the development concepts of "no distortion, high transients" and "no noise, high resolution" as part of the Monumental Products 10000 Series to commemorate the 100th anniversary of Yamaha’s founding. While it was similar to 1982’s NS-2000 in using only single materials, no composite materials, with a pure beryllium dome midrange and tweeter and a pure carbon fiber woofer, over the five years since then the accuracy and application area of computer simulation had progressed dramatically to significantly improve the non-resonant and high rigidity characteristics of the cabinet and woofer frame. And in the beryllium midrange and tweeter, a tradition since the S-1000M, the newly introduced bronze diffuser, GC (giant crystal) beryllium diaphragm and GC beryllium bobbin reduced transmission loss due to large crystallization of beryllium, further enhancing sound resolution and response.

Contrary to its conservative appearance, it incorporated many innovations like the cabinet’s 12-ply laminated birch plywood round baffles made with the same "bending and kneading" process used in making grand piano sideboards, and the plasma spot-welded network that directly wired each part without using solder. The cabinet size was almost the same as the NS-2000, with a similar American walnut finish taken one grade higher, but thanks to the golden color of the brass diffuser this speaker came to be easily distinguished as a special one.



A simple and delicate two-way bookshelf model that took speaker manufacturing back to its basics.



Appearing in 1988 in the midst of the popular price speaker competition showing signs of turning into a war of attrition in the Japanese market, the NS-1 Classic had nothing, even in terms of its technical and design elements, to do with preceding Yamaha speakers. But in appearance there was no mistaking that it was a Yamaha HiFi bookshelf speaker and you could even go so far as to call it a reincarnation of the old NS-690 series.

No longer using high-tech materials, it had a simple design featuring a colorless mica hybrid PP cone woofer and a soft dome tweeter made of undyed cotton treated with a minimal amount of phenol forming resin. With an aluminum-nickel magnetic circuit it is clear that it was strongly intended as a return to speaker building basics, and that intention was restated equally in its bare tweeter dome and defenselessly affixed white felt. The six-sided real birch wood cabinet featured a full urethane finish on all sides, and it retailed for 59,500 yen per unit at the time of its release. Knowing how good it was from the point of view of modern values, that price seems surprisingly reasonable, but for customers of the day it was no doubt a difficult choice to have to select between a popular price speaker that was respectable because it visibly weighed 30kg and a unit like this that was not even a third of that. The price of the NS-1 Classic went up to 65,000 yen per unit in 1993, but it continued to be produced for twelve years until 1999, slowly and steadily gaining supporters. The technology of the A-PMD (Advanced Polymer-injected Mica Diaphragm) unit continues to be used in Yamaha speakers.



The first-ever active servo speaker system, using the new AST method to expand the limits of low-frequency playback.



Widely used in Yamaha’s subwoofers and home theater products, the YST (Yamaha Active Servo Technology) method was originally developed to expand the low-frequency reproduction limits of HiFi speakers. Known as AST at the time, the YST method involves two technologies, one the Air Woofer, which emits the small amplitude sound waves within the cabinet from the port as large amplitude waves by adjusting the cabinet volume and port size to meet certain conditions, and the other Negative Impedance Drive, which drives the speaker to cancel the impedance of the voice coil so the apparent impedance of the speaker is zero, the former performed by a speaker and the latter by an amplifier.

Released in 1989 as a set containing an AST-S1 dedicated speaker and AST-A10 dedicated amplifier with a combined product number, the AST-1 was the first active servo speaker system to utilize this AST method. Its dedicated speaker was even smaller than the NS-10M, a 16cm two-way mounted in an A4 size 6-liter capacity cabinet, and for a dedicated amplifier it had a thin two-channel power amplifier with line-level input. In its front panel it had a special cartridge slot for changing the amplifier’s operating characteristics according to the speaker, with a cartridge included with each speaker.

The catalog was full of phrases straight out of a dream, such as, "28Hz playback that lets you listen to the fundamental of a piano’s lowest note, not its harmonics" and "Ultra-mega bass reproduction without having to fill your room with a giant speaker," but while the actual sound did not betray listeners’ expectations, the product’s planned double duty for both HiFi and AV use did not win the support of audiophiles. The component-type AST product line of speaker-amplifier sets stopped at the four speakers and two amplifiers already released that year. On the other hand, the Tiffany series of AST method built-in amplifier superwoofers and compact stereos that were released the same year were a hit, and the sublime GF-1 active speaker system released in 1991 with a superwoofer bearing the revised YST name earned good reviews for its sound quality.



A flawlessly superior active speaker system that sought to completely reproduce the real value of the unit itself.



The desire to eliminate the uncertainty of not knowing which amplifier is going to be driving the speakers they make is natural and probably the same for all developers. If you trace things back further to the unit development stage, even the passive network interposed between an amplifier and unit is going to end up being called the product of a compromise.

The GF-1, which came to be known as an active speaker of integrity encapsulating an active crossover and a drive amplifier directly connected one-to-one with all speaker units, removed all such fateful constraints. It was the culmination of the Yamaha HiFi speaker aiming for the full realization of the true value of the speaker itself and of the unit itself. It was designed with a two-part configuration, the upper half of its 140cm tall, 150kg cabinet housing a three-way speaker element and the lower half a YST superwoofer element. Its four drive amplifiers and active crossover units per channel were attached as four independent modules to the back of the superwoofer, and with a massive external power supply that itself weighed 25kg supplying each of the four amplifier modules with independent power it was a truly heavy piece of equipment. The crossover slope and cutoff frequency were completely fixed and could not be adjusted from the outside in any way, with only fine adjustments of up to ±2.5dB to each module’s input level available to the user. From this it can be seen that the developers intended the system to be perfectly tuned and did not intend the balance to be changed easily.

The tweeter and midrange were of course made of pure beryllium, but rather than using the vacuum deposition process of the past it went as far as using a forged beryllium dome developed for and used in only this model. Its pair of large and small woofers likewise used a Kevlar cone and forged beryllium cap specific to this model, and the magnet utilized a voice coil with reduced diameter and dendritic crystal aluminum-nickel to lighten the motion of the diaphragm system. The tweeter and midrange magnets were also composed of dendritic crystal aluminum-nickel. The gold deposition method was performed on each unit’s diaphragm in an effort to damp the slight squeal of beryllium and produce uniform tone across all units. Overall it was built like it was meant to be the crowning glory, and if there was just one thing left undone it would probably be that it was not possible to use a forged beryllium woofer cone. As Yamaha’s speaker development changed course for a new era of focus on the home theater, the GF-1 put a period at the end of the pure beryllium development story that had played out since the NS-1000M.



A micro speaker for near-field listening equipped with the world’s first magnesium cone unit.



Released in 2003, this was the first newly developed HiFi model in years, a high-grade micro speaker geared toward near-field listening. In addition to the world’s first practical application of the magnesium cone, specially developed just for use in this 7cm full range unit, in sound and appearance its lavish and ingenious construction featured eye-catching details like a wine red mirror finish cabinet carved from a solid block of mahogany and a hemispherical brass and solid wood stand given the same clear coating and polishing as real brass instruments in Yamaha’s wind instrument factory.

Among practical metals magnesium combines maximal vibration absorption and minimal specific gravity to make it a material with physical properties ideal for audio use, but its application in speaker diaphragm construction had been limited mainly by the problem of its limited workability. Once that problem was overcome, the small magnesium unit’s tone combined excellent response with a tranquility unexpected from a small caliber speaker to produce a unique and distinctive color. Because of its wide-range, low efficiency design with a 70Hz~45kHz (-10dB) playback frequency response and 80dB/2.83V.1m sound pressure level it tended to work with a limited selection of drive amplifiers and in that sense it was a difficult speaker that required the hand of a master, but when combined with a good amplifier its refined and vivid expressive power worthy of exactly the kind of copy found in that microcosm of music, the catalog.


Linking tradition to tomorrow. The new Yamaha HiFi audio.