The ARP Omni: An Orchestra In A Road Case

Not many bands could afford to tour with a brass section or a group of string players, but through the Omni and its siblings, ARP harnessed the power of electronic music to put an orchestra on every stage.

ARP Omni (2019) by Robert GilliamThe Alan R. Pearlman Foundation

The Art of the Portable Orchestra

In popular music in the 1970s, there was an ongoing demand for some way to simulate, even crudely, the sound of the orchestra that often backed up singers or bands in the recording studio. Synthesizers of the day could do that, but only playing one note at a time: they were monophonic, like a flute or oboe. For one keyboardist to simulate an orchestra, their instrument needed to be polyphonic, capable of playing chords without difficulty.

The Problem of Polyphony

Theoretically one could do this by building one synthesizer per voice and tying them all together to be played from one keyboard – but that sort of solution would be heavy, complicated, and expensive. Instead, ARP took a hint from the electric organ, which was fully polyphonic. Using a divide-down circuit, the sound of one oscillator running at a very high frequency could be tuned down to an appropriate pitch for any key the musician pressed… including all of them at once.

Other manufacturers were using divide-down designs to make organs, and were already experimenting with tweaking those sounds to simulate strings. ARP would leverage this technology – both borrowed and home-grown – to create instruments that would define the sounds of pop music for a long time to come.

ARP String Ensemble in home studio setting (2018) by Lisa Bella DonnaThe Alan R. Pearlman Foundation

The String Ensemble

ARP's first foray into the realm of divide-down "string machines" was 1974’s String Ensemble. It was distributed by ARP in the USA, but was actually designed and built by the Dutch manufacturer Eminent BV, who used the circuit in their famous Eminent 310 organ. The String Ensemble had basic tone controls and a split keyboard that allowed for two sounds – say, violin and cello – to be played with two hands in their appropriate ranges.

ARP String Solina front view (2020) by Dave Spiers/Alex BallThe Alan R. Pearlman Foundation

The Solina

The Solina (1975), another Eminent-built string machine, added a synthesizer voice similar to that of ARP's Explorer I that could be blended with the strings or output separately.

ARP String Solina side view (2020) by Dave Spiers/Alex BallThe Alan R. Pearlman Foundation

Not many were imported, however, because ARP was about to take an important step of its own...

ARP Omni (2019) by Robert GilliamThe Alan R. Pearlman Foundation

Enter the Omni

In late 1975, ARP brought its own divide-down synthesizer to the public. The Omni was capable of producing multiple sounds at once, including strings, brass, and a variety of other sounds like piano, electric piano, organ, synthesizer, and more. A monophonic Bass synthesizer filled out the bottom end.

ARP Ad Omni (1977) by ARP InstrumentsThe Alan R. Pearlman Foundation

This ad for the Omni featured a soundsheet – a flexible plastic sheet, grooved like a 45 single, that was bound into the magazine. It could be torn out by the reader, placed on a turntable, and played like a record in order to hear a demonstration of the Omni's sounds.

An audio demonstration like this could be quite important for sales – especially when to musicians used to organs, monophonic synths, and simple string machines, the Omni's claims to orchestral glory would seem impossible at first glance.

And if you were wondering what that Omni demonstration soundsheet might have sounded like... wonder no more, here it is! This is a playback of the Omni demo in its entirety – you can even see the corners of this square record going by as it spins.

This little video by musician LtPicard combines a tour of the Omni's features with some tasteful playing, including pitch-perfect bits and pieces from some famous Omni-heavy recordings of the 1970s, such as Equinoxe by Jean-Michel Jarre.

The Omni was used extensively by Joy Division and later New Order. Its lush sounds can be heard throughout this song ("Age of Consent") and many others by the two bands; the Omni was even called "the sound of Joy Division" by some.

ARP Omni-2 (2019) by Alex BallThe Alan R. Pearlman Foundation

The Omni-2

The Omni-2, released in 1977, featured not only the blank-and-orange livery that characterized all newer ARP gear, but improved sound and a new keyboard that provided much better articulation of complex lines when played on non-string sounds like piano and pipe organ.

Here are The Cars using the Omni's famous filter sweep in the track "Moving in Stereo" from their first album.

The Omni was the primary keyboard featured in the song "Dirty Mind" by Prince. Check out the chords underlying the song and gluing it all together.

ARP Ad Quadra (1979) by ARP InstrumentsThe Alan R. Pearlman Foundation

The Quadra

Building a new symphonic keyboard seemed a good way for ARP Instruments to reach an enthusiastic audience while retooling existing and proven electronics into new roles… and this time around, ARP truly struck gold.

1978's Quadra was a Frankenstein monster of a synthesizer, containing several previous ARP circuits wired together in a consolidated keyboard that allowed for massive simultaneous orchestrations. The Bass, String, and Poly Synthesizers were based on the relevant circuits from the Omni, and the Lead synthesizer was essentially an Odyssey voice with simplified controls. It had a pressure-sensitive keyboard, and settings of the front panel controls could be stored in up to 16 instantly-recallable presets.

ARP Spec Sheet Quadra p1 (1979) by ARP InstrumentsThe Alan R. Pearlman Foundation

The spec sheet for the Quadra gives an indication of its complexity, as well as a look at under-the-hood improvements like a lush phase shifter that could add body and movement to any or all of the four sounds, and a built-in mixer to dial in sound combinations to perfection.

The Quadra's relatively high price prevented it from being as all-pervasive as the Omni and Omni-2 had been, but it still had a large and loyal following, most notably Tony Banks of Genesis, who used the Quadra on many of the band's most popular albums (here's a live version of "Abacab" from 1981, where the Quadra dominates all the instrumental sections).

ARP Spec Sheet Quadra p2 (1979) by ARP InstrumentsThe Alan R. Pearlman Foundation

This 5-minute video by YouTuber LtPicard demonstrates several examples of the remarkable combined sounds the Quadra could produce so easily.

This 1979 musical segment features a jazz trio with Cleve Pozar and two keyboardists (Michael Brigida on the left and John Shykun on the right) playing a large array of ARP synthesizers: we count one Axxe, one Pro/DGX, one 2600, two each of the Odyssey and 16-Voice Electronic Piano... and a pair of dueling Quadras anchoring the arrangement. The host of this TV show seems stunned by the idea of this "mechanical band," and the trio's performance must have been equally stunning to a 1979 audience.

ARP Spec Sheet Quartet p1 (1979) by ARP InstrumentsThe Alan R. Pearlman Foundation

The Quartet

ARP released one more divide-down synthesizer, the Quartet (1979). Featuring Brass, Strings, Piano, and Organ, it was a revoiced version of the Italian Siel Orchestra – in much the same way that the original String Ensemble and Solina had come from Eminent in the Netherlands. It was far more affordable than the Quadra and thus available to a much broader audience.

ARP Omni (2019) by Robert GilliamThe Alan R. Pearlman Foundation

The Sound of a Symphony... and More

Even after decades, ARP’s orchestral keyboards still shine brightly on hundreds of hit records. And it all began with a keyboardist who wanted to carry an entire orchestra to a gig in a road case.

Credits: Story

Story by Mike Metlay; editorial contributions by Dina Pearlman and Mary Lock; The Alan R. Pearlman Foundation

Credits: All media
The story featured may in some cases have been created by an independent third party and may not always represent the views of the institutions, listed below, who have supplied the content.
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