The Korg M1 is a synthesizer and music workstation manufactured by Korg from 1988 to 1995. The M1 was advertised as a 'workstation' rather than a synthesizer, integrating composition and performance features into a single device. It features 16-voice polyphony, high-quality digital samples (including drum sounds), an integrated 8-track sequencer and digital effects processing. It is one of the bestselling synthesizers in history, selling an estimated 250,000 units.^[4][5]

Korg's chief engineer, Junichi Ikeuchi, led the hardware engineering design of the M1.^[6] Whereas previous synthesizers had shipped with sounds chosen for different markets, the Korg chairman, Tsutomu Kato, and his son Seiki decided that their synthesizers should use the same sounds internationally. Korg assembled an international team to develop the sounds for the M1. To create a deep blown bottle sound, the team played a pan flute over a large sake bottle.^[7]

The M1 features a 61-note velocity- and aftertouch-sensitive keyboard, 16-note polyphony, a joystick for pitch-bend and modulation control, an eight-track MIDI sequencer, separate LFOs for vibrato and filter modulation, and ADSR envelopes. Data can be stored on RAM and PCM cards.^[7]

The M1 has a ROM with four megabytes of 16-bit PCM tones — a large amount at the time — including instruments that had not been used extensively in mainstream music. The sounds include sampled attack transients, loops, sustained waveforms and percussive samples. The timbres include piano, strings, acoustic guitar, woodwinds, sitar, kalimba, wind chimes and drums. Fact described the sounds as "wonderfully, endearingly wonky ... each one managed to sound simultaneously realistic and synthetic all at once".^[7][8]

The M1 also features effects, including reverb, delay, chorus, tremolo, EQ, distortion, and Leslie simulation, an innovative inclusion at the time. According to Sound on Sound, none of the M1's features were unique, but were implemented and combined in a new way.^[7]

The M1 was released in 1988 and was manufactured until 1995, selling an estimated 250,000 units.^[7] Reviewing it for Sound on Sound in 1988, Tony Hastings wrote that it was "destined to be big, very big", with "sensational" sounds and extensive features that outperformed its competitors.^[9] It was widely used in popular music and stock music in the late 80s and early 90s.^[8] The piano and organ presets were used in 1990s house music, beginning with Madonna's 1990 single "Vogue".^[8]

In 2002, the Sound on Sound journalist Mark Vail wrote that the M1 was the bestselling synthesizer in history, though he noted that Korg had not verified the sales figures.^[7] Both Sound and Sound and Fact described it as the most popular synthesizer of all time.^[7][8] Fact attributed the success to its sampling and sequencer features, which allowed musicians to produce entire tracks without a studio before the rise of digital audio workstations.^[8]

Following the success of the M1, Korg expanded its lineup with several series of new workstations, including the T-series in 1989, the 01-series in 1991, the X-series in 1993, and the N-series in 1996. The 01/W built upon the M1’s AI synthesis with the enhanced AI2 system, which introduced additional effects and digital waveshaping. Rack-mountable versions of the M1 include the M1R and the more affordable M3R. Additionally, Korg released the M1EX and the M1REX rackmount, both featuring sounds from the T-series.^[4][10]

Korg released a software version of the M1 in 2006 as part of the Korg Legacy Collection. This digital version features 8-part multitimbrality, 256-note polyphony and presets from all 19 optional ROM cards.^[11] A free update added the entire preset collection from the T-series workstations to the M1 plugin.^[12]