Sequential Circuits J-Wire PRO ONE Synthesizer SN 7689

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"You will not find a cleaner or nicer unmolested/unmodified original Sequencial Circuits Pro One model 100 than this one!

This is the real deal, Vintage and powerful SCI PRO ONE! Not a modern day clone made from Chinese parts.

Made in the USA in San Jose, California.

Only 7,000 Version 2 Pro Ones were ever made total!

*** Fully restored and serviced! (details below) ***

This is the very much more desirable "J Wire" version 2 of the Pro One. SERIAL # 7689

There are 3 versions of the Pro One, this is the most desirable version, here is some information a prospective buyer should know about buying a Pro One:


Version 1:
Serial Numbers 1500 and below are Version 1's and have their power supply transformers bolted directly to the Main Circuit board.

This is not a good setup since the heavy transformer can and has been known to break the boards, they also can suffer from arc-ing between the mains power circuit traces on the circuit board.

Version 2 (the version I am selling here):
Serial Numbers 1501 ~ 8500

This is the version that saw the Transformer relocated mounted to the rear of the chassis solving the V1 problems.

This version still retained the J-Wire keybed contact system and is the most reliable and desirable version of the Pro One.

Version 3:
Serial Numbers 8500 and up.

These were the same as the V2 but the keybed was changed to a "Mushy" keybed that used a Membrane for contacts.
Over time this membrane decays, turns into crud added to the dirt that builds up and was notoriously unreliable.

Turbo CPU / MIDI modification:
The Pro one I am selling has not been modified, it is unmolested/unmodified.
The Turbo CPU/MIDI mod is nice, but not really necessary, a faster CPU isn't needed in these unless you plan to play the
synth with lightning fingers or via an external sequence that is so fast it has no musical value to it.
The Mod at retail usually costs under $120 and only takes a few minutes to install, that said, it does not add thousands of
dollars to the value of a pro one, just $120, and then you end up drilling holes into the synth for the MIDI jacks.
Although I personally prefer MIDI, this is a mono synth, I used it via a simple MIDI-CV converter in which you can find
right here on ebay for cheap. When you come across Pro One's with Turbo CPU's installed its a good sign that their original
CPU's were bad and they couldn't find a replacement for them, to me that is usually a sign of gear that hasn't been all that well
taken care of. Granted things do happen like power surges, lightning strikes etc. This is why all my studio gear is powered via a
Huge military line conditioner and individual surge suppressors and varistors on every outlet. Haven't had a piece of gear suffer
from power spikes etc since 1994.

WHAT HAS BEEN DONE TO THE PRO ONE FOR SALE IN THIS EBAY AD:
All potentiometers and switches have been properly cleaned with De-oxit, none are scratchy or noisy.
They are all original, no modern "not quite right" replacements, especially on the slide switches in which correct originals are obsolete and unobtainable.
All 4 Power regulators have been replaced even though this synth didn't need it, its the first thing you do in repair/restoration/servicing of vintage gear.
All electrolytic capacitors have been replaced too (thats the second thing you do in restoring/servicing vintage gear after the regulators).
Keybed cleaned and serviced. All notes work fine.
Chassis and front panel cleaned (what little cleaning it needed that is).
INSIDE of the chassis cleaned.

The Pro One has built in factory Sequencer and Arpeggiator!
Includes a CD-ROM containing PDF copies of the Technical Manual, Scematics, and Operation Manuals.
Rear panel has CV, GATE, GATE/CLICK IN, FILTER CV IN, AUDIO IN, and AUDIO OUT JACKS."