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!

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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.

68 Visitor comments
June 29, 2009 @ 5:39 am
Love it !!! Next to my minimoog this is in my opinion the best little mono synth you can get for the money. More fun than the moog, easy to use, great little sequencer. Down side is the build quality of a Nettos christmas cracker but the bass and guts of an atomic weapon.. you ill not be dissapointed with this if you can get one. Will only be getting more and more valuable.....
April 12, 2009 @ 4:46 am
Zlaya - HoJo did use Pro-One on Human's Lib, but he more used 2 x Moog Prodigy's for the main sounds...however at his 20th anniversary gig he used a Pro-One triggered from a TR-808 for basslines using the arpeggiator
April 2, 2009 @ 5:07 am
I play Pro One after 1985
I buy & send my ProOne.( In french for Team: HumanFly Clermont-Ferrand )...Like a moog system the pro one are complicated with mixer sound and sequencer and apergiator. Not multitimbral
If you build sounds write on paper the selection. NoteBook all time...
Sequencial Circuit sound are different moog or arp.
But this is a big analogic synthetiser...
I use ProOne for sequencer Bass or Fx sequence...
But for fx only
Pro One The big boss... I like this vintage...
Sorry for my bad english! Bye!...
January 14, 2009 @ 10:29 pm
I just ran across this old photo of me using this keyboard in 1980.. Very cool axe.
Steve Axtell
January 14, 2009 @ 3:33 pm
Still one of the best mono synths ever made. I never get enough of that sound. Perfect match for Berlin School electronic music.
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  • Check Prices on eBay
  • The link above will take you to a 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

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