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Ensoniq Corp. was an American electronics manufacturer, best known throughout the mid-1980s and 1990s for its musical instruments , principally samplers and synthesizers .

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65-530: In spring 1983, former MOS Technology engineers Robert "Bob" Yannes , Bruce Crockett , Charles Winterble, David Ziembicki, and Al Charpentier formed Peripheral Visions . The team had designed the Commodore 64 , and hoped to build another computer. To raise funds, Peripheral Visions agreed to build a computer keyboard for the Atari 2600 , but the video game crash of 1983 canceled the project and Commodore sued

130-497: A pure-play semiconductor foundry , so they had to join a chip-building company to produce their new CPU. MOS was a small firm with good credentials in the right area, the east coast of the US. The team of four design engineers was headed by Chuck Peddle and included Bill Mensch . At MOS they set about building a new CPU that would outperform the 6800 while being similar to it in purpose and much less expensive. The resulting 6501 design

195-471: A common filter and/or amplifier circuit shared among all the voices. The result is a synthesizer that can play chords, provided all the notes start and end at the same time ( homophony ). For example, playing a new note on top of notes already held might retrigger the volume envelope for the entire sound. Monophonic synthesizers with more than one oscillator (such as the ARP 2600 ) can often be patched to behave in

260-423: A complete sound-generating mechanism for each key in the keybed (e.g., a piano has a string and hammer for every key, and an organ has at least one pipe for each key.) When any key is pressed, the note corresponding to that key will be heard as the mechanism is activated. Some clavichords do not have a string for each key. Instead, they will have a single string which will be fretted by several different keys. Out of

325-486: A few minor differences: an added on-chip clock oscillator, a different functional pinout arrangement, generation of the SYNC signal (supporting single-instruction stepping), and removal of data bus enablement control signals (DBE and BA, with the former directly connected to the phase 2 clock instead). It outperformed the more-complex 6800 and Intel 8080 , but cost much less and was easier to work with. Although it did not have

390-500: A large number of audio outputs to a mixer. The stops or drawbars on the organ modify the signal sent from the audio-generating system, and the keyboard switches the mixer's channels on and off. Those channels which are switched on are heard as notes corresponding to the depressed keys. In classical music, a definition of polyphony does not only mean just playing multiple notes at once but an ability to make audiences perceive multiple lines of independent melodies. Playing multiple notes as

455-537: A note one octave lower, the frequency of the oscillator is divided by two. Polyphony is achieved so long as only one of each note in the scale is played simultaneously. A forefather of octave divider synth and electronic organs. Octave divider technology similar to Novachord was used. Polyphonic ensemble keyboard consists with one synth per key (totally 60 synthesizers), based on octave divider Patchable polyphonic synthesizer consists with three synths per key (totally 144 synthesizers), based on octave divider. In

520-455: A number of varieties, including double, triple, and quadruple ocarinas, which use multiple chambers to extend the ocarina's otherwise limited range, but also enable the musician to play more than one note simultaneously. Harmonic ocarinas are specifically designed for polyphony, and in these instruments the ranges of the chambers usually overlap to some extent (typically at the unison, third, fourth, fifth, seventh or octave). Cross-fingering enables

585-490: A par with Lexicon's offerings, but at affordable prices. Despite these strengths, early (1980s) Ensoniq instruments suffered from reliability and quality problems such as bad keyboards (Mirage DSK-8), under-developed power-supply units (early ESQ-1), or mechanical issues (EPS polypressure keyboard). Through the early and mid-1990s, much effort was focused on improving the reliability of the products. The company did not manage to reinvent its workstation concept in order to survive

650-443: A paraphonic manner, allowing for each oscillator to play an independent pitch which is then routed through a common VCF and VCA . The earliest polyphonic synthesizers were built in the late-1930s, but the concept did not become popular until the mid-1970s. Harald Bode 's Warbo Formant Orguel, developed in 1937, was an archetype of a voice allocation polyphonic synthesizer. Novachord by Hammond Organ Company , released in 1939,

715-399: A polyphonic instrument is a (classical) piano , on which the player plays different melody lines with the left and the right hand - depending on music style and composition, these may be musically tightly interrelated or may even be totally unrelated to each other, like in parts of Jazz music. An example for monophonic instruments is a trumpet which can generate only one tone (frequency) at

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780-481: A single chamber to span an entire octave or more. Recorders can also be doubled for polyphony. There are two types of double recorder; drone and polyphonic. In the drone type, one tube is tuned exactly like a regular recorder with a range of approximately two octaves, and the other tube is a drone and plays the tonic note of the scale. The polyphonic recorder has two tubes with a range of one major sixth. With overblowing, some notes can be played an octave higher, but it

845-514: A time, except when played by extraordinary musicians. A monophonic synthesizer or monosynth is a synthesizer that produces only one note at a time, making it smaller and cheaper than a polyphonic synthesizer which can play multiple notes at once. This does not necessarily refer to a synthesizer with a single oscillator ; the Minimoog , for example, has three oscillators which are settable in arbitrary intervals , but it can play only one note at

910-768: A time. Well-known monosynths include the Minimoog, the Roland TB-303 , the Korg Prophecy , and the Korg Monologue . Duophonic synthesizers, such as the ARP Odyssey and Formanta Polivoks built in the 1970s and 1980s respectively, have a capability to independently play two pitches at a time. These synthesizers have at least two oscillators that are separately controllable, and a duophonic keyboard that can generate two control voltage signals for

975-414: A whole, such as a rhythm from a chord pattern, is not polyphony but homophony . A classical violin has multiple strings and indeed is polyphonic but harder for some beginners to play multiple strings by bowing. One needs to control the pressure, speed and angle well for one note before having an ability to play the multiple notes at acceptable quality expected by the composers. Therefore, even though

1040-406: Is a forefather product of frequency divider organs and polyphonic synthesizer. It uses octave divider technology to generate polyphony, and about 1,000 Novachords were manufactured until 1942. Using an octave divider a synthesizer needs only 12 oscillators – one for each note in the musical scale . The additional notes are generated by dividing down the outputs of these oscillators. To produce

1105-575: The Gravis Ultrasound card. In 1994, production began on PC sound cards for home computers. The design of the video-game console Atari Panther also included the OTIS chip, though the product never reached series production. A dedicated version of OTTO, ES5530/35 OPUS, was developed for AT-bus sound cards, featuring built-in joystick and CD-ROM interface. Ensoniq's sound cards were popular and shipped with many IBM PC compatibles . Many games in

1170-458: The 6501's advantage of being able to be used in place of the Motorola 6800 in existing hardware, it was so inexpensive that it quickly became more popular than the 6800, making that a moot point. The 6502 was so cheap that many people believed it was a scam when MOS first showed it at a 1975 trade show. They were not aware of MOS's masking techniques and when they calculated the price per chip at

1235-447: The 6502 chip. At Commodore, Peddle convinced the owner, Jack Tramiel , that calculators were a dead end, and that home computers would soon be huge. However, the original design group appeared to be even less interested in working for Jack Tramiel than it had for Motorola, and the team quickly started breaking up. One result was that the newly completed 6522 (VIA) chip was left undocumented for years. Bill Mensch left MOS even before

1300-586: The 6502 was, the company itself was having problems. At about the same time the 6502 was being released, MOS's entire calculator IC market collapsed, and its prior existing products stopped shipping. Soon they were in serious financial trouble. Another company, Commodore Business Machines (CBM), had invested heavily in the calculator market and was also nearly wiped out by TI 's entry into the market. A fresh injection of capital saved CBM, and allowed it to invest in company suppliers in order to help ensure their IC supply would not be upset in this fashion again. Among

1365-459: The 6502—were achieving a success rate of 70 percent or better. This meant that not only were its designs faster, but they also cost much less as well. When the 6501 was announced, Motorola launched a lawsuit almost immediately. Although the 6501 instruction set was not compatible with the 6800, it could nevertheless be plugged into existing motherboard designs because it had the same functional pin arrangement and IC package footprint. That

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1430-417: The 650x line from MOS, including Rockwell International , GTE , Synertek , and Western Design Center (WDC) . A number of different versions of the basic CPU, known as the 6503 through 6507, were offered in 28-pin packages for lower cost. The various models removed signal or address pins. Far and away the most popular of these was the 6507 , which was used in the Atari 2600 and Atari disk drives. The 6504

1495-773: The Commodore Semiconductor Group superfund site. Most of the MOS chips are named according to following rules, which shows used technology (logic gate design): 40°07′27.9″N 75°25′07.2″W  /  40.124417°N 75.418667°W  / 40.124417; -75.418667 Polyphony (instrument) Polyphony is a property of musical instruments that means that they can play multiple independent melody lines simultaneously. Instruments featuring polyphony are said to be polyphonic . Instruments that are not capable of polyphony are monophonic or paraphonic . An intuitively understandable example for

1560-529: The Commodore takeover, and moved home to Arizona. After a short stint consulting for a local company called ICE, he set up the Western Design Center (WDC) in 1978. As a licensee of the 6502 line, their first products were bug-fixed, power-efficient CMOS versions of the 6502 (the 65C02 , both as a separate chip and embedded inside a microcontroller called the 65C150). But then they expanded

1625-566: The EPS sampler) and ES5505 OTIS (used in the EPS16+ sampler and the VFX line of synthesizers featuring 21 voices). Finally, ES5506 OTTO drove all subsequent 32-voice machines (SD-1/32, TS10/12, ASR-10/88) and the dual-OTTO machines (KT, MR, ZR). The latest incarnation, ES5548 OTTO-48, was used in the final line of Ensoniq studio products (ASR-X, FIZMO). Ensoniq also developed an effects DSP, ES5510 ESP, that

1690-777: The Proteus 2500 module – the E-Mu/Ensoniq division was dissolved and support for legacy products was discontinued soon afterward. Ensoniq entered the instrument market with the Mirage sampling keyboard in 1985. At the price of USD$ 1695 it cost significantly less than previous samplers such as the Fairlight CMI and the E-MU Emulator . Starting with the ESQ-1 , they began producing sample-based synthesizers . Following

1755-604: The Record which featured the band using the EPS sampler and SQ-80 cross wave synthesizer. The company had much success with the SQ product line starting in the early 1990s. This was a lower-cost line that included the SQ-1 (61 keys), SQ-2 (76 keys) and SQ-R ( rack-mounted , with no keys or sequencer), as well as KS-32 with full 76-keys weighted piano-keyboard. Later versions were produced with 32 sound-generating voices. The company's heyday

1820-480: The VFX synthesizer, high-quality effects units were included, in addition most synthesizer and all sampler models featured disk drives and/or RAM cards for storage. The manuals and tutorial documents were clearly written and highly musician-oriented, allowing the users to quickly get satisfactory results from their machines. In 1988, the company enlisted the Dixie Dregs in a limited edition promotional CD Off

1885-406: The ability to "fix" its masks after they had been produced. This meant that as flaws in the design were discovered, the masks could be removed from the aligners, fixed, and put back in. This allowed them to rapidly drive out flaws in the original masks. The company's production lines typically reversed the numbers others were achieving; even the early runs of a new CPU design—what would become

1950-460: The aftermath; those that survived did so by finding other chips to produce. MOS became a supplier to Atari , producing a custom single-chip Pong system. Things changed dramatically in 1975. Several of the designers of the Motorola 6800 left Motorola shortly after its release, after management told them to stop working on a low-cost version of the design. At the time there was no such thing as

2015-424: The aligners by the truckload. This meant that if a flaw was found in the design, it would cost a significant amount of money to fix it, as all the older masks would have to be thrown out. In contrast, with Micralign there was only one mask per aligner, so there was no inherent cost in replacing the mask if need be, although the cost, and especially time, of producing these master masks was considerable. MOS developed

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2080-522: The classical guitar, is polyphonic, as are various guitar derivatives (including the harpejji and the Chapman stick ). Multiphonics can be used with many regular wind instruments to produce two or more notes at once, although this is considered an extended technique . Explicitly polyphonic wind instruments are relatively rare, but do exist. The standard harmonica can easily produce several notes at once. Multichambered ocarinas are manufactured in

2145-518: The company, operating under the name GMT Microelectronics ( G reat M ixed-signal T echnologies ), reopened MOS Technology's original, circa-1970 one-micrometre process fab ( semiconductor fabrication plant ) in Audubon , Montgomery County , Pennsylvania that Commodore had closed in 1993. The plant had been on the EPA's National Priorities List of hazardous waste sites since October 4, 1989. This

2210-433: The current industry yield rates, it did not add up. But any hesitation to buy it evaporated when both Motorola and Intel dropped the prices on their own designs from $ 179 to $ 69 at the same show in order to compete. Their moves legitimized the 6502, and by the show's end, the wooden barrel full of samples was empty. The 6502 would quickly go on to be one of the most popular chips of its day. A number of companies licensed

2275-422: The early-to-mid-1970s, the voice allocation technology with digital keyboard scanning was independently developed by several engineers and musical instrument manufacturers, including Yamaha , E-mu Systems , and Armand Pascetta (Electro Group). The Oberheim Polyphonic Synthesizer and Sequential Circuits Prophet-5 were both developed in collaboration with E-mu Systems. Voice allocation technology

2340-566: The firm basically became Commodore's production arm, they continued using the name MOS for some time so that manuals would not have to be reprinted. After a while MOS became the Commodore Semiconductor Group (CSG) . Despite being renamed to CSG, all chips produced were still stamped with the old "MOS" logo until week 22/23 of 1989. MOS had previously designed a simple computer kit called the KIM-1 , primarily to "show off"

2405-458: The full-custom ICs for music and effects which were developed in house. While the core keyboard products were generally successful, there were some quality problems and increasing competition from Asian companies. An attempt to diversify into hearing aids was unsuccessful and put the company in financial peril. In the mid-nineties, they developed a line of very cost-effective sound cards which sold millions of units. In January 1998, ENSONIQ Corp.

2470-557: The keys that share a single string, only one may sound at a time. The electric piano and clavinet rely on the same principles to achieve polyphonic operation. An electric piano has a separate hammer, vibrating metal tine and electrical pickup for each key. With a few exceptions, electric organs consist of two parts: an audio-generating system and a mixing system. The audio-generating system may be electronic (consisting of oscillators and octave dividers) or it may be electromechanical (consisting of tonewheels and pickups), and it sends

2535-548: The late MS-DOS era supported the Ensoniq Soundscape either directly or through General MIDI . In addition, Ensoniq devised an ISA software audio emulation solution for their new PCI sound cards that was compatible with most contemporary IBM PC games. It is speculated that this was an important factor in Creative Lab's acquisition of Ensoniq, because Creative/E-MU was struggling with legacy compatibility at

2600-458: The line greatly with the introduction of the 65816 , a fairly straightforward 16-bit upgrade of the original 65C02 that could also run in 8-bit mode for compatibility. Since then WDC moved much of the original MOS catalog to CMOS, and the 6502 continued to be a popular CPU for the embedded systems market, like medical equipment and car dashboard controllers. After Commodore's bankruptcy in 1994, Commodore Semiconductor Group, MOS's successor,

2665-488: The lowest- and highest-note. When two or more keys are pressed simultaneously, the lowest- and highest-note will be heard. When only one key is pressed, both oscillators are assigned to one note, possibly with a more complex sound. Paraphonic synthesizers, such as the Solina String Ensemble or Korg Poly-800 , were designed to play multiple pitches at the same time by using multiple oscillators, but with

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2730-407: The maximum number of notes is already sounding when an additional key is pressed. There are several ways to implement this: Modern synthesizers and samplers may use additional, multiple, or user-configurable criteria to decide which notes sound. Almost all classical keyboard instruments are polyphonic. Examples include the piano , harpsichord , organ and clavichord . These instruments feature

2795-540: The mid and late '90s. In 1986, after making an agreement with Apple Computer , the same ES5503 DOC (Digital Oscillator Chip, marketed as "Q-Chip") used in the Mirage sampler (DSK-8, DSK-1, DMS-1), ESQ-1, ESQ-M and SQ-80 synthesizers, and SDP-1 piano module, was incorporated into the Apple II GS personal computer. Later engines, with 16-bit sample playback and internal digital filters, were ES5504 DOC-II (used in

2860-600: The multiple synthesizers. One of the most popular polyphonic synth featuring patch memories, also used E-mu's technology. One notable early polyphonic synthesizer, the Prophet 5 released in 1978, had five-voice polyphony. Another notable polyphonic synth, the Yamaha CS-80 released in 1976, had eight-voice polyphony, as did the Yamaha GX-1 with total 18 voice polyphony, released in 1973. Six-voice polyphony

2925-515: The new company, claiming that it owned the keyboard project. Renaming itself as Ensoniq, the new company instead designed a music synthesizer. Ensoniq grew rapidly over the next few years with the success of the Mirage and the ESQ-1. The plant in Great Valley, Pennsylvania employed nearly 200 people and housed the manufacturing facility. A number of successful products followed which all included

2990-580: The several companies were LED display manufacturers, power controllers, and suppliers of the driver chips, including MOS. In late 1976, CBM, publicly traded on the NYSE with a market capitalization around US$ 60 million , purchased MOS (whose market cap was around US$ 12 million ) in an all-stock deal. Holders of MOS received a 9.4 percent equity stake in CBM on the condition that Chuck Peddle would join Commodore as chief engineer. The deal went through, and while

3055-608: The site. Announced in March 1999, GMT would have provided foundry services based on TelCom's Bipolar and SiCr (silicon chromium) Thin Film Resistor processes and would have been a licensed alternate source for TelCom's Bipolar based products, with production running at 10,000 5-inch semiconductor wafers per month, producing CMOS , BiCMOS, NMOS, bipolar and SOI ( silicon on insulator ) devices. In 2000, GMT Microelectronics discontinued operations and abandoned all of its assets at

3120-408: The sound, often with a keyboard to trigger the oscillators. However, multiple oscillators working independently are a considerable challenge to implement. To double the polyphony, not only must the number of oscillators be doubled but the electronics must also function as a switch connecting keys to free oscillators instantaneously, implementing an algorithm that decides which notes are turned off if

3185-651: The success of these products, Ensoniq established a subsidiary in Japan in 1987. Ensoniq products were highly professional. Strong selling points were ease-of-use and their characteristic "fat", rich sound (generally thought of as being an "American" quality, as opposed to the "Japanese" sound which was more "digital" and somewhat "cold"). After the Mirage, all Ensoniq instruments featured integrated sequencers (even their late '80s and early '90s samplers ) providing an all-in-one "digital studio production concept" instrument. These were often called "Music Workstations". Starting with

3250-707: The time with their higher-performance PCI audio solutions. MOS Technology MOS Technology, Inc. ("MOS" being short for Metal Oxide Semiconductor ), later known as CSG (Commodore Semiconductor Group) and GMT Microelectronics , was a semiconductor design and fabrication company based in Audubon, Pennsylvania . It is most famous for its 6502 microprocessor and various designs for Commodore International 's range of home computers . Three former General Instrument executives, John Paivinen, Mort Jaffe and Don McLaughlin, formed MOS Technology in Valley Forge, Pennsylvania in 1969. The Allen-Bradley Company

3315-421: The violin family of instruments are misleadingly considered (when bowing) by general untrained musicians to be primarily monophonic, it can be polyphony by both pizzicato (plucking) and bowing techniques for standard trained soloists and orchestra players. The evidence can be seen in compositions since the 17th century such as Bach sonatas and partitas for unaccompanied solo violin . The electric guitar, just like

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3380-457: Was a similar inversion in pricing. The 6800 sold in small lots for $ 295 ; with no other changes than using a Micralign , the same design could sell for $ 42 . The change to the Micralign revealed a further advantage. Previously the masks were mass-produced by photography companies like Kodak , who would make tens of thousands of copies of a master mask, or " reticle ", and ship the masks to

3445-685: Was acquired by Creative Technology Ltd. for $ 77 million. The acquisition was focused on the sound-card technology of the Ensoniq Audio-PCI. The musical products division, which was in financial trouble, was merged with E-mu Systems to form the E-Mu/Ensoniq division of Creative. Over the next three years the Ensoniq operation in Pennsylvania was gradually dismantled and shut down. After releasing an entry-level E-mu MK6/PK6 and Ensoniq Halo keyboards in 2002 – essentially keyboard versions of

3510-417: Was bought by its former management for about $ 4.3 million , plus an additional $ 1 million to cover miscellaneous expenses including a United States Environmental Protection Agency (EPA) license. Dennis Peasenell became CEO. In December 1994, the EPA entered into a Prospective Purchase Agreement (limiting the company's liability in exchange for sharing the costs of cleanup) with GMT Microelectronics. In 1994,

3575-474: Was complete. In 1974 Perkin-Elmer publicly introduced the Micralign system, the first projection scanner. Instead of placing the mask on the surface of the chip, it held it far from the surface and used highly accurate optics to project the image. Masks now lasted for thousands of copies instead of tens, and the flaw rate of the chips inverted so that perhaps 70% of the chips produced would work. The result

3640-411: Was due to a 1978 leak of trichloroethylene (TCE) from an underground 250-gallon concrete storage tank used by Commodore Business Machines in the semiconductor cleaning process. Leaks from the tank had caused the local groundwater to become contaminated with TCE and other volatile organic compounds (VOCs) in 1978. By 1999 GMT Microelectronics had $ 21 million in revenues and 183 employees working on

3705-475: Was enough to allow Motorola to sue. Allen-Bradley sold back its shares to the founders, sales of the 6501 basically stopped, and the lawsuit would drag on for many years before MOS was eventually forced to pay US$ 200,000 in fines. In the meantime MOS had started selling the 6502 , a chip capable of operating at 1  MHz in September 1975 for a mere US$ 25 . It was nearly identical to the 6501, with only

3770-609: Was in the early 1990s when the VFX synthesizers offered innovative performance and sequencing features (and terrific acoustic sounds), along with the ASR series of 16-bit samplers which also integrated synthesis, effects, and sequencer into a single-unit digital studio. The TS synthesizers followed the legacy of the VFX line, improving several aspects such as the polyphony , effects engine, sample-loading capabilities and even better synth and acoustic sounds. The DP series of effects rack-mount units offered parallel processing and reverb presets on

3835-549: Was looking to provide a second source for electronic calculators and their chips designed by Texas Instruments (TI). In 1970 Allen-Bradley acquired a majority interest in MOS Technology. In the early 1970s, TI decided to release their own line of calculators, instead of selling just the chips inside them, and introduced them at a price that was lower than the price of the chipset alone. Many early chip companies were reliant on sales of calculator chips and were wiped out in

3900-413: Was placed directly on the surface of the chip, which had the significant disadvantage that it sometimes pulled away materials from the chip, which were then copied to subsequent chips. This caused the mask to become useless after about a dozen copies, and resulted in the vast majority of chips having fatal flaws; for a complex chip like the 6800, only about 10% of the chips would work once the masking process

3965-417: Was sometimes used in printers. MOS also released a series of similar CPUs using external clocks, which added a "1" to the name in the third digit, as the 6512 through 6515. These were useful in systems where the clock support was already being provided on the motherboard by some other source. The final addition was the "crossover" 6510 , used in the Commodore 64 , with additional I/O ports. However successful

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4030-407: Was somewhat similar to the 6800, but by using several design simplifications, the 6501 would be up to four times faster. Previous CPU designs, like the 6800, were produced using a device known as a contact aligner . This was essentially a complex photocopier , which optically reproduced a CPU design, or "mask", on the surface of the silicon chip. The name "contact" referred to the fact that the mask

4095-401: Was standard by the mid-1980s. With the advent of digital synthesizers , 16-voice polyphony became standard by the late 1980s. 64-voice polyphony was common by the mid-1990s and 128-note polyphony arrived shortly after. There are several reasons for providing such large numbers of simultaneous notes: Synthesizers generally use oscillators to generate the electric signal that forms the basis of

4160-493: Was used in the machines from VFX on and the standalone FX units DP/2 and DP/4. OTTO-48 generation uses its greatly enhanced successor, ES5511 ESP V2. A combination of OTTO and ESP, ES5540 OTTOFX, was also developed and sold. The Ensoniq ES5505 OTIS/OTISR2, and ES5510 ESP (Ensoniq Signal Processor) were also used in various arcade games . They were all manufactured on the CMOS process. OTTO was licensed to Advanced Gravis for use in

4225-483: Was used to assign the limited 8-voices per manual into the notes. It was succeeded by the portable Yamaha CS-80 (1976), which was successful and became one of the most popular polyphonic analog synths. In 1974, E-mu developed the polyphonic technologies, and in 1977, released the 4060 Polyphonic Keyboard and Sequencer. It was developed under the collaboration with E-mu Systems. LEO used Armand Pascetta's polyphonic keyboard ( c.  1975 ) to control

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