Sequential Circuits Pro One

Sequential Pro One Image

The Sequential Pro One is a wicked little monosynth! It comes from the same period and genre as the Roland SH-101 and Moog Prodigy. The Pro One was basically Sequential's attempt at taking their legendary Prophet 5 poly-synth and packing it into a compact, inexpensive, monophonic analog synth! It has two VCOs, a great 4-pole lowpass filter, two ADSR envelopes (one for filter), and a compact three-octave keyboard. With a Pro-One, you can easily create punchy analog bass-lines and leads or quirky analog synth effects.

The Pro One is an extremely flexible synth with lots of modulation possibilities (ie: the filter, VCO B and LFO can modulate VCO A or B frequencies or pulse widths, or the VCF). There's also an onboard sequencer, something common on many Sequential synths but not often found on other monosynths of the time. It is very basic, however, storing only two patterns and up to 40 notes max. Also, only pitch info is recorded (and in step time only); you can not assign a note duration to any notes. So it's basically a short melodic sketch-pad...but useful. Also onboard is an arpeggiator which has UP and UP/DOWN patterns.

Sequential Pro One Image

The Pro One is relatively simple and intuitive to use, fun, educational and responsible for some of the coolest and hardest basslines in electronic music today! It is used by Hardfloor, Überzone, the Prodigy, Cirrus, Fluke, Depeche Mode, Download, Banco De Gaia, Vince Clarke, New Order, Freddy Fresh, Mouse on Mars, Prince, Soft Cell, Richard Barbieri and Sigue Sigue Sputnik.

But since you can't always find one (about 10,000 were produced), or one that works properly... Wine Country Sequential has come up with a solution! WCS has been servicing old Sequential gear for years, as well as selling repair parts, etc. They have developed the Pro One Software Synthesizer Plug-In, an awesome replica of the original Pro One, both in look and sound! It has some added features and is an incredible way to easily add the sound of the Pro One to your music!

Lookup Sequential Circuits Pro One Prices

The link above will take you to an eBay search for this synth to see active listings with more images, specs and information. If you don't find it there, try looking in our forum marketplace. Our marketplace gets thousands of visits every week so make sure to check back often if you want to buy or sell a synth.

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Are you looking to buy or sell a Sequential Circuits Pro One? Post an ad in Gear For Sale or a request in Gear Wanted. For spare parts and repair services check out Gear Services & Other Goods. Our forums also has a Buyer’s Guide section where you can ask for advice on buying synthesizers.

70 Visitor comments
October 23, 2010 @ 7:05 pm
A great little synth. I learned on an ARP Odyssey, but that translated over to the Pro easily. Could never afford a Moog. Mine's gone a bit flaky with the transformer oscillating (which I need to replace one of these days). Chose the Pro since it did stuff nothing else in it's price range could.
September 30, 2010 @ 1:35 pm
I've been maintaining a web site that tracks the eBay sales of Pro~Ones going back to Feb 2008. There is some other stuff and resources there too. Please have a look:
Will Puckett
September 17, 2010 @ 9:53 am
My favorite of my lot as well. I have owned at least one of everything during my career and the Pro-One I am keeping. I have a Kenton MIDI interface installed and a couple of odd Mods like filter Envelope inversion and an LFO mod that allows for odd FM programming. A very versatile synth. Just add midi and WOW!
September 10, 2010 @ 1:49 pm
Brilliant analog mono synth! This is by far my favourite analogue synth (I've got minimoog's ARP's Rolands etc). It has such a great sounding filter and excellent user design. The pro-one is still very under-rated, I paid £750 for mine which was mint (only one owner) and has the crucial J-wire keyboard.
August 22, 2010 @ 3:29 am
IMO the Mopho does not sound quite the same as a Pro One, so as not to mislead anyone. It lacks a few features but inexplicably has a "fatter" sound in the same way my Evolver does not sound quite as good as the Pro One. But each has its own uses.
Finally replaced the One I sold 8 years ago with a very sweet condition-rare case the keys work great! Put it through a digital delay or effects and you have sonic gold.
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Rated 4.45 (885 Votes)

  • Check Price
  • The link above will take you to an eBay search for this synth to see active listings. If you don't find it there, try looking in our forum marketplace or post a wanted classified.
  • Specifications
  • Polyphony - Monophonic
  • Oscillators - 2 VCOs (CEM-3340 chips): : VCO A saw/pulse, VCO B saw/tri/pulse, Noise
  • LFO - saw, tri, pulse
  • Filter - CEM-3320 Filter chips: 4-pole lowpass with Cutoff, Resonance, ADSR Envelope, Keyboard Tracking
  • VCA - ADSR Env
  • Keyboard - 36 keys
  • Arpeg/Seq - Arepg: UP, UP/DOWN patterns, Latch mode; SEQUENCER: 2 patterns of pitch info only, 40 note capacity.
  • Control - CV/GATE
  • Date Produced - 1981 - 1984
  • Resources & Credits
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    Additional information provided by DAC Crowell.

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