What Is an Omnichord? Suzuki's Electronic Autoharp, Explained

An Omnichord is an electronic autoharp: a chord instrument Suzuki introduced in 1981. You press a chord button with one hand and sweep a touch-sensitive strum plate with the other, and it plays a harp-like run made only of that chord’s notes, with optional drums and a bass line underneath. Suzuki still makes one today, the OM-108, first shown in January 2024.

How does an Omnichord work?

Suzuki Musical Instrument Corporation is based in Hamamatsu, Japan, and was founded in 1953 by Manji Suzuki, who started out building harmonicas. Its first Omnichord, the OM-27, came out in 1981, around the same time as a simpler sibling called the Tronichord, which had 27 chords but no rhythms and only two volume knobs. Every Omnichord since has the same three parts: chord buttons, a strum plate to their right, and a rhythm section.

The chord buttons sit in three rows: major on top, minor in the middle, 7th on the bottom. Each column is one root note. The OM-27’s 27 buttons cover nine roots (Eb, Bb, F, C, G, D, A, E and B), so Db, F# and Ab are missing. In 1984 the OM-36 and OM-84 brought 36 buttons for all 12 roots, and on the OM-84, pressing two or three buttons in one column gives you more chord types:

Those 48 combinations plus the 36 single-button chords make 84, which is where the OM-84 got its name. Almost every later model kept the system.

The roots follow the circle of fifths. On the OM-108 the columns read Db, Ab, Eb, Bb, F, C, G, D, A, E, B, F#. That order is the layout’s best trick. In C major, F, C and G sit side by side on the major row, and Dm, Am and Em sit side by side on the minor row just to their right, so all six common chords of the key fit in a block six columns wide. G7 is directly under G.

The strum plate, which Suzuki calls SonicStrings, is a touch-sensitive strip that covers four octaves. Sweep a finger along it and it plays the notes of the chord you are holding in order, low at one end and high at the other. A slow sweep sounds like a harp, a fast flick sounds like a strummed chord, and a single touch plays one note. Press a new chord button and the same plate plays the new chord. An arpeggiator plays a chord’s notes one by one at a set speed for you. The strum plate leaves the speed and direction to your finger, which is why it feels like playing strings.

The rhythm section adds drums and an automatic bass line that follows your chord. The OM-27 has six rhythms (Rock, Waltz, Slow Rock, Latin, Fox Trot and Swing). The OM-84 has ten, plus a chord memory that stores a sequence of up to 51 chords. The OM-27 has a memory switch that keeps the last chord playing after you let go of its button, and the OM-108 has a Chord Hold button that does the same, so you can tap a chord and take your hand away.

A good first exercise: start a rock rhythm, press C and sweep the plate once per bar from bottom to top. Change to Am, then F, then G, one chord per bar, and you are playing the I vi IV V progression behind your own voice. C, F and G are neighbors on the top row, and Am sits three columns right of C on the minor row, so your left hand barely moves.

Is the Omnichord a synth? What’s inside

Loosely, yes. The Omnichord generates its own sound with electronic circuits, which is what a synthesizer does, but it plays like a preset instrument. There are no oscillator, filter or envelope controls for building a sound from scratch. You pick a voice, then set the volume and the sustain (how long each strummed note rings).

What is inside depends on the model:

• OM-27, OM-36 and OM-84: analog circuits. The OM-27 and OM-36 have a single harp sound with adjustable sustain. The OM-84 has two strum plate voices, one with vibrato, each with its own volume knob, so you can blend them.
• OM-100 through OM-300 (1989 to 1996): sampled digital voices, which brought sounds such as guitar, piano, banjo, jazz organ and flute. MIDI out arrived on some of these models in 1989.
• OM-108 (2024): ten voices. Omni 1 and Omni 2 use analog circuitry to recreate the OM-84 sound, and the other eight (harp, celeste, acoustic piano, guitar, FM piano, organ, vibes and banjo) are digital.

The OM-108’s MIDI out sends the chords, the strum plate and the drums on separate channels, so the strum plate can play an external synth or a software instrument while the Omnichord picks the notes. It has no MIDI in.

Omnichord vs autoharp (and vs the QChord)

The autoharp came first by about a century. Charles F. Zimmermann’s US patent for it was issued in 1882. It is a zither with chord bars across the strings, and each bar carries felt pads that mute every string outside its chord, so you press a bar, strum all the strings, and hear only that chord. A typical modern autoharp has 36 strings and 12, 15 or 21 chord bars covering major, minor and dominant 7th chords.

Suzuki kept the two-hand motion and swapped the strings for electronics. After production of the OM series stopped with the OM-300 in 1996, Suzuki redesigned it as the QChord in 1999, with a new body, more sounds, a better speaker and a slot for song cartridges.

The autoharp wins on touch: real strings respond to how hard and where you pluck, and a good player can pick out a melody between strums. It needs no power, either. In exchange you tune 36 strings, and you only get the chords on your bars. The common 12-bar layout (C, F, G, Bb, Dm, Am, Gm and five 7th chords) is built around the keys of C, F and G, so a song in E or B is out of reach. The Omnichord has no strings to tune, plays in every key from 1984 on, runs on batteries with a built-in speaker, and brings its own drums and bass. The QChord adds a pitch bend wheel and far more sounds, and its optional song cartridges hold full backing arrangements of popular songs to play along with.

Songs that use the Omnichord

Six recordings with a documented Omnichord part, oldest first:

• Eurythmics, “Love Is a Stranger” (1982): the Omnichord’s harp sound.
• Brian Eno and Daniel Lanois, “Deep Blue Day” (1983): a slowed-down recording of an Omnichord, on the album Apollo: Atmospheres and Soundtracks.
• U2, “Trip Through Your Wires” (1987): Lanois played it on The Joshua Tree, plugged into the Edge’s delay units and guitar amp.
• Gorillaz, “Clint Eastwood” (2001): Damon Albarn used the OM-300’s Rock 1 rhythm preset.
• David Bowie, “America” (2001): he played an Omnichord on the Simon & Garfunkel song at the Concert for New York City.
• Meshell Ndegeocello, The Omnichord Real Book (2023): she composed the album on one, and it won the first Grammy for Best Alternative Jazz Album.

Away from records, the Omnichord’s everyday job is backing a singer. One button and one sweep per bar make a complete accompaniment, which is why it turns up in classrooms, choirs and music therapy sessions, where nobody needs to read music to join in.

Is the Omnichord still made?

Yes. Suzuki planned a new Omnichord for its 70th anniversary in 2023, and the OM-108 made its public debut at the NAMM Show on January 25, 2024. It keeps the classic layout and adds a few things:

• 38 buttons and 108 chords. The two new types are sus4 and add9. Press a major button with the 7th button one column to its left for sus4 (C major plus F 7th gives Csus4: C, F, G), or with the minor button one column to its left for add9 (C major plus F minor gives Cadd9: C, E, G, D).
• A four-octave strum plate with the ten voices listed above, and ten rhythms, from Rock 1 to Bossa Nova.
• A keyboard mode that turns the chord buttons into a 20-key melody keyboard and the strum plate into drum pads.
• MIDI out, a 10 cm speaker, and eight AA batteries (sold separately) for about eight hours of playing.

Every older model, from the OM-27 to the QChord, is only sold used now, and a working vintage unit often costs close to what a new OM-108 does. Our guide to what an Omnichord costs and why covers new and vintage prices and what to check before buying.

To find out whether chord-button playing suits you before spending that much, our free online chord player strums the chords of any of the 24 major and minor keys in your browser. On iPhone, Gelato Chord, which we make, is built in the spirit of the Omnichord: seven keys play the seven chords of your key, beside a melody plate of twelve strings where the strings in the chord you hold light up. It is free to download with one $4.99 in-app purchase. It works in one key at a time, where an Omnichord puts all 12 roots under your fingers.