The Yamaha DX21 is a digital controlled bi-timbral programmable digital FM synthesizer with a four operator synth voice generator which was released in 1985. It uses

sine wave A sine wave, sinusoidal wave, or just sinusoid is a curve, mathematical curve defined in terms of the ''sine'' trigonometric function, of which it is the graph of a function, graph. It is a type of continuous wave and also a Smoothness, smooth p ...

-based

frequency modulation (FM) synthesis Frequency modulation synthesis (or FM synthesis) is a form of sound synthesis whereby the frequency of a waveform is changed by modulating its frequency with a modulator. The frequency of an oscillator is altered "in accordance with the amplitude ...

. It has two FM tone generators and a 32-voice

random-access memory Random-access memory (RAM; ) is a form of computer memory that can be read and changed in any order, typically used to store working Data (computing), data and machine code. A Random access, random-access memory device allows data items to b ...

(RAM), 32 user voices and 128

read-only memory Read-only memory (ROM) is a type of non-volatile memory used in computers and other electronic devices. Data stored in ROM cannot be electronically modified after the manufacture of the memory device. Read-only memory is useful for storing sof ...

(ROM) factory preset sounds. As a programmable synth, it enables users to create their own unique synthesized tones and

sound effect A sound effect (or audio effect) is an artificially created or enhanced sound, or sound process used to emphasize artistic or other content of films, television shows, live performance, animation, video games, music, or other media. Traditi ...

s by using the algorithms and oscillators. The instrument weighs 8 kg (17.6 lbs). On its release, it sold for $795.

Keyboard

The keyboard has 61 keys which are not velocity-sensitive to harder or softer key presses. It can produce eight note polyphony, which means up to eight keys can be pressed at once. In split keyboard mode, the polyphony limit is still eight notes, but there is a maximum of four for the lower half and four for the upper half. In mono mode, the DX21 can play only one note, unless the keyboard is split; if the keyboard is split, the DX21 can do one mono voice for the lower split and one mono voice for the upper split.

MIDI and jacks

The DX21 is

MIDI MIDI (; Musical Instrument Digital Interface) is a technical standard that describes a communications protocol, digital interface, and electrical connectors that connect a wide variety of electronic musical instruments, computers, and re ...

compatible, which enables performers to use the DX21 to control other digital instruments (e.g., a drum machine or other synth), or use other MIDI-compatible controllers or devices to play the DX21's synthesized sounds. The DX21 has 1/4" jacks for plugging in a sustain pedal, a

portamento In music, portamento (plural: ''portamenti'', from old it, portamento, meaning "carriage" or "carrying") is a pitch sliding from one note to another. The term originated from the Italian expression "''portamento della voce''" ("carriage of the v ...

pedal, and a volume

expression pedal An expression pedal is an important control found on many musical instruments including organs, electronic keyboards, and pedal steel guitar. The musician uses the pedal to control different aspects of the sound, commonly volume. Separate expres ...

and an input for a BC-1 breath controller. The DX21 has MIDI in, out and thru jacks, which enable the instrument to be connected to a computer, drum machine, sequencer, or other MIDI-compatible device. The CPU is a Hitachi HD63803XP and the sound generation chip is the YM2164 (OPP), a variant of the YM2151 (OPM). The DAC is a YM3012. The instrument has an un-backlit LCD panel which indicates the name of the voice or sound and provides information on the status of the instrument. A split point can be set on the keyboard, to enable part of the keyboard to be used with one sound and part for another sound. For example, a bass sound could be put on the left side of the keyboard, and a flute sound on the other half. The DX21 also has a modulation wheel and a pitch bend wheel. The two tone generators are output via two output jacks. Thus to hear tone generator A and tone generator B, a user would need to plug in two cables into a stereo

keyboard amplifier A keyboard amplifier is a powered electronic amplifier and loudspeaker in a wooden speaker cabinet used for amplification of electronic keyboard instruments. Keyboard amplifiers are distinct from other types of amplification systems such as g ...

, PA system, or other audio gear.

Sounds and effects

The 128 ROM preset voices can be grouped into 16 categories: piano; electric piano; organ; strings; brass; plucked strings; '' comping'' (accompanying instruments); percussion 1; percussion 2; lead synth; other keyboards; wind reeds; bass; and three sound effect categories, which include sounds such as "racing car", "helicopter", "whistling", and basic sounds such as "LFO noise". Users can save their own newly-created synth tones to an external cassette recorder. It has an onboard

chorus effect Chorus (or chorusing, choruser or chorused effect) is an audio effect that occurs when individual sounds with approximately the same time, and very similar pitches, converge. While similar sounds coming from multiple sources can occur naturally, ...

. The

low frequency oscillator Low-frequency oscillation (LFO) is an electronic frequency that is usually below 20 Hz and creates a rhythmic pulse or sweep. This is used to modulate musical equipment such as synthesizers to create audio effects such as vibrato, tremolo ...

(LFO) has modulators for amplitude and pitch, using saw, square, triangle wave shapes. For attack-decay-sustain-release ( ADSR) control, also called "envelope", there are four envelopes.

Users

Notable users include:

Hardfloor Hardfloor is a German electronic music duo, consisting of Oliver Bondzio and Ramon Zenker. Their most famous track is "Acperience 1" (often titled more simply as "Acperience" on many compilation albums) and chosen by Feargal Sharkey as one of h ...

Level 42 Level 42 is an English jazz-funk band formed on the Isle of Wight in 1979. They had a number of UK and worldwide hits during the 1980s and 1990s. Their highest-charting single in the UK was " Lessons in Love", which reached number three on the ...

Brother Beyond Brother Beyond were a British pop band who had success in the pop rock genre in the late 1980s. Biography The group's first four singles, "I Should Have Lied", "How Many Times", "Chain-Gang Smile" (produced by Don Was), and an early version of ...

Xiu Xiu Xiu Xiu ( ) is an American experimental band, formed in 2002 by singer-songwriter Jamie Stewart in San Jose, California. Currently, the line-up consists of Stewart (the only constant member since formation) and Angela Seo. The band's name co ...

Astral Projection Astral projection (also known as astral travel) is a term used in esotericism to describe an intentional out-of-body experience (OBE) that assumes the existence of a subtle body called an " astral body" through which consciousness can functio ...

Technotronic Technotronic was a Belgian electronic music project formed in 1987 by Jo Bogaert, who originally gained popularity in Europe as a solo artist with various new beat projects, including Acts of Madmen and Nux Nemo. Together with rapper Manuela K ...

Vangelis Evangelos Odysseas Papathanassiou ( el, Ευάγγελος Οδυσσέας Παπαθανασίου ; 29 March 1943 – 17 May 2022), known professionally as Vangelis ( ; el, Βαγγέλης, links=no ), was a Greek composer and arranger of ...

, and

Norman Cook Norman Quentin Cook (born Quentin Leo Cook, 31 July 1963), also known by his stage name Fatboy Slim, is an English musician, DJ, and record producer who helped to popularise the big beat genre in the 1990s. In the 1980s, Cook was the bassist f ...

(Fatboy Slim).

DX100

The DX100 was also released in 1985. It uses similar electronics to provide a keyboard with 49 minikeys that is smaller and easier to carry. The DX100 is a 4-operator FM synthesizer that is monotimbral. It has no filters or effects. It has 192 preset voices and 24 user-programmable voices. It has MIDI capabilities and MIDI in/out and thru jacks. It has a single mono output, a single footswitch jack for a sustain pedal or portamento pedal and a BC1 breath controller jack.

Comparison with DX7

The DX21 has 4 operators and 8 algorithms. The DX7 has 6 operators and 32 algorithms.

References

External links

Yamaha DX21 Owner's manual
{{DEFAULTSORT:Yamaha DX21 DX21 Polyphonic synthesizers Digital synthesizers