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Sequential Circuits Pro One

“Sequential Circuits Pro-One Synthesizer. Condition is Used. This synth is in excellent condition all around. It sounds great and all features work. It was professionally serviced a few years ago.” Click here to search for synths on eBay

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Sequential Circuits Pro One

“The original Pro-One monophonic synthesizer from 1981. Please refer to online reviews of this legendary instrument for detailed technical specifications. Suffice to say this is a classic analogue synth with extensive modulation capabilities, powerful filter with the SCI unique resonance, two oscillators, sequencer and arpeggiator. There is only one Pro-One in terms of build and sound quality; naming no names, recent clones are decent enough machines but simply that: machines rather than instruments. It was mostly triggered by a MIDI converter box rather than played direct during its working life, so the keyboard is responsive and without the triggering problems which some examples exhibit. There are slight though noticeable abrasions on the right-hand wooden sides (see photos) but otherwise it’s in a fine condition.” Click here to search for synths on eBay

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Sequential Circuits Pro One

“The original Pro-One monophonic synthesizer from 1981. Please refer to online reviews of this legendary instrument for detailed technical specifications. Suffice to say this is a classic analogue synth with extensive modulation capabilities, powerful filter with the SCI unique resonance, two oscillators, sequencer and arpeggiator. There is only one Pro-One in terms of build and sound quality; naming no names, recent clones are decent enough machines but simply that: machines rather than instruments. Sure, the keyboard, or rather, keybed, is notoriously flakey, but not on this example. It was mostly triggered by a MIDI converter box rather than played direct during its working life. There are slight though noticeable abrasions on the right-hand wooden sides (see photos) but otherwise it’s in a fine condition.” Click here to search for synths on eBay

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Sequential Circuits Pro One

“Absolute perfect condition! Recently tuned up to %100 by experienced technician. Very clean, calibrated, comes with power cable. Sounds amazing! This model has the desirable j-wire style key contacts” Click here to search for synths on eBay

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Sequential Circuits Pro One

“Sequential Circuits PRO-ONE Analog Synthesizer. Condition is Seller refurbished – Keyboard has been leveled and the J wires reset/repaired. Comes with custom flight case.” Click here to search for synths on eBay

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Sequential Circuits Pro One

“Nice! vintage original Sequential Circuits PRO-ONE Analog Synthesizer mono moog. Condition is Seller refurbished – Keyboard has been leveled and the J wires reset/repaired. Comes with custom flight case. ” Click here to search for synths on eBay

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Sequential Circuits Pro One

“Nice! vintage original Sequential Circuits PRO-ONE Analog Synthesizer mono moog. Condition is Seller refurbished – Keyboard has been leveled and the J wires reset/repaired. Comes with custom flight case.” Click here to search for synths on eBay

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Sequential Circuits Pro One

“Nice! vintage original Sequential Circuits PRO-ONE Analog Synthesizer mono moog. Condition is Seller refurbished – Keyboard has been leveled and the J wires reset/repaired. Comes with custom flight case.”
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Sequential Circuits Pro One

“This one is in excellent cosmetic condition and working 100%. It is ready to be played and needs nothing! As the title says, this one has the Turbo CPU Upgrade with Midi (no holes were drilled into the metal housing). It does have the j-wire keyboard so it can be serviced in the future.”
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Sequential Circuits Pro One

“My beloved Sequential Circuits Pro-One analog synthesizer with original operation manual and technical manuals in their original SCI binders.

I am the second owner of this iconic synth.

J-wire keybed model – also with the improved power supply arrangement chassis mounted OFF the PCB.

In great condition with some wear here and there, some markings on the lower keys – see photos.

Please note that volume pot is a bit tilted, not a huge deal unless you’re ocd.

Newer solid walnut side cheeks.

Just had in for service including: replaced bypass caps; cleaned pots, switches, key contacts; tuned & scaled.

Sounds great, classic sounds and textures unlike anything else.

Would love to keep it but I am going a different direction and have limited space.”
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Sequential Circuits Pro One Project Machine

“GOT THIS IN AN ESTATE SALE THE GUY HAD A LOT OF THIS KIND OF STUFF AND THE PERSON HAVING THE SALE SAID HE WAS A MUSICIAN OF SORTS AND ALL THE EQUIPMENT WORKED. I HAVE NO IDEA HOW TO WORK THIS THING I FOUND OUT. IT WAS MISSING THE FUSE AND RED COVER WHICH I ORDERED ON EBAY AND PUT IT IN AND THE MACHINE TURNED ON. MY NEIGHBOR BROUGHT OVER HIS CRATE AMP AND WE HOOKED THIS PRO ONE UP TO IT AND IT SEEMED TO CHANGE SOUNDS BUT NEITHER OF US HAVE ANY KNOW HOW TO ADJUST THIS OR WHAT THE THIS THING CAN DO. SELLING IT AS-IS, NO WARRANTY OR RETURNS. NOTE IT IS MISSING ONE KNOB AND HAS SOME MINOR SCRATCHES ON THE UNDERSIDE AND A COUPLE NICKS IN THE WOODEN SIDES.”
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Sequential Circuits Pro One


SEQUENTIAL CIRCUITS PRO ONE ANALOG J-WIRE KEYBOARD / SYNTHESIZER.
SERIAL NUMBER = 6330 Includes Operations Manual and Additional Schematics!

This was the Astonishlngly FAB Keyboard / Synth used by Vince Clarke for Most of the Awesome Sounds heard on the LPs; ‘Upstairs At Eric’s’ & (partially) on ‘You And Me Both’.

Please, keep in mind that although this Keyboard / Synth was one of the COOLEST synths ever created in the history of mankind , Some of the Models did ship from the factory with the following Terrible Faults:

(1) All Pro Ones with Serial Numbers ABOVE # 8500 used the Cheap, Terrible (and Faulty!) MEMBRANE Keyboards.

(2) All Pro Ones with Serial Numbers BELOW # 1500 were the ones with the Power Supply (including Heavy Transformer) Mounted on the Printed Circuit Board!

This particular Pro One does NOT fall into Either of these 2 catagories so, you are getting the Preferred J-WIRE Keyboard as well as the also Much more preferred keyboard that has the Power Suppy (including Heavy Transformer!) Mounted on the Metal Chassis where it is much more Stable and less likely to Crack the PC Board which was a common occurrence with those keyboards w/ Serial #’s under #1500. ”
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Sequential Circuits Pro One

“SEQUENTIAL CIRCUITS PRO ONE ANALOG J-WIRE KEYBOARD / SYNTHESIZER.
SERIAL NUMBER = 6330 Includes Operations Manual and Additional Schematics!

This was the Astonishlngly FAB Keyboard / Synth used by Vince Clarke for Most of the Awesome Sounds heard on the LPs; ‘Upstairs At Eric’s’ & (partially) on ‘You And Me Both’.

Please, keep in mind that although this Keyboard / Synth was one of the COOLEST synths ever created in the history of mankind , Some of the Models did ship from the factory with the following Terrible Faults:

(1) All Pro Ones with Serial Numbers ABOVE # 8500 used the Cheap, Terrible (and Faulty!) MEMBRANE Keyboards.

(2) All Pro Ones with Serial Numbers BELOW # 1500 were the ones with the Power Supply (including Heavy Transformer) Mounted on the Printed Circuit Board!

This particular Pro One does NOT fall into Either of these 2 catagories so, you are getting the Preferred J-WIRE Keyboard as well as the also Much more preferred keyboard that has the Power Suppy (including Heavy Transformer!) Mounted on the Metal Chassis where it is much more Stable and less likely to Crack the PC Board which was a common occurrence with those keyboards w/ Serial #’s under #1500.

Having said that, the reason I am selling my Pro One is that suddenly, inexplicably the keyboard just STOPPED functioning properly! Only a few of the keys (4-5?) now trigger at all. Not sure what led up to this but, I did notice last year that some of the keys were starting to make a ‘crackly’ noise when pressed and were often failing to completely trigger their related notes.

That being said, ALL of the other functions of this Keyboard/Synth operate Correctly. I have tested and re-tested EVERY KNOB, EVERY SLIDER SWITCH, EVERY OTHER FUNCTION of this Fabulous Synth and EVERYTHING ELSE OPERATES CORRECTLY AND VERY WELL Including the SEQUENCER (both A & B Patterns) and BOTH the BEND & MODULATION WHEELS.
All is in Good order EXCEPT for the Keyboard. So, therefore I must sell this Item AS IS Due to a faulty Keyboard. Also, note that as pictured the very highest key has broken off at the fragile little plastic knob where it hooks up underneath to the chassis. I have provided pictures illustrating this and will also provide the complete key and essential little spring so, that you can try and repair it by gluing it back on if you’d like.”
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Sequential Circuits Pro One

“Super-Cool Early 80’s Vintage Analog Synth!

Sequential Circuits PRO-ONE

I recently purchased it from the original owner!

She used it briefly in the day, for “left hand bass” in a home studio

*WORKING* .. meaning everything works

ALL controls work as expected.

SOUNDS GREAT!

Serial #9080 = Membrane Keyboard

Consequently, a few keys are “Fussy” ..

Fyi ~ I’m too busy with B-3 & Leslie restoration.

No time to spend time on this.

Leaving detailing to you. I gave it a careful light external cleaning .. that’s it.

*POWER SWITCH is very STIFF..

Leave it in ON position and use power strip?

*Dusty

**Wood sides very dry

***Typical nicks & scratches

( over the last 40 yrs, I’ve owned many Moog / ARP / Oberheim / Sequential ..

Rhodes / Wurli / B-3 / Roland / Yamaha / misc rare analog synths )

Please Check My Feedback.” Click here to search for synths on eBay

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Sequential Circuits Pro One

“Sequential Circuits Pro One Vintage Keyboard Synthesizer.

Item has been tested and is not functioning properly.

Keyboard function is not working properly, light stays on and machine thinks a key is constantly being pressed, gate stays open.

Selling AS-IS

Please see all photos for more information.

(3065195-2)”
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Sequential Circuits Pro One

“This auction is for one used Sequential Circuits Pro One synthesizer. I have had it for 8 years and I have replaced all key bushings, had the power cable replaced, had the mod wheel replaced, and had the oscillators tuned and calibrated. It’s in amazing condition. I have seen several Pro Ones in person and this is the best condition one I have seen. You will not be disappointed. This is the J-Wire keyboard version, but the bus bar and J-wires have not been cleaned (by me) in some time and a lot of keys double-trigger at the moment. Just a warning so that you don’t think it’s defective. 😉 I typically controlled it via CV since that was easier than taking it apart and cleaning it. Plenty of tutorials online for that. It’s just time-consuming, but anyone can perform it. I am only selling this because I have had some recent financial trouble. I really don’t want to sell it. My loss is your gain. 🙁 ”
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Sequential Circuits Pro One

“For sale: Sequential Circuits Pro 1 Vintage Analogue Monophonic Synthesiser in excellent, working condition.

In truly superb cosmetic condition for its age (see photos)”

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Sequential Circuits Pro One

“Absolute classic, sounds amazing, newly serviced, pots & keys all glitch free, showing age appropriate signs of wear & tear but generally in good condition.”
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Sequential Circuits Pro One

“For sale: Sequential Circuits Pro 1 Vintage Analogue Monophonic Synthesiser in excellent, working condition.

In truly superb cosmetic condition for its age (see photos) ”
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Sequential Circuits Pro One

“Sequential Circuits Pro-One 80’s Vintage Monophonic Synthesiser. Condition is Used.
This very nice example of the classic synthesizer comes with a bound copy of the user manual from the USA. The synthesizer has been fully serviced by Cyberwave EMS this month and the JWire keyboard fully re-bushed. It has a few signs of minor wear on a few keys and minor scratches and scuffs on the underside and side wooden planels but nothing that can’t be repaired or rectified.
It is fully functional and plays to full specifications. It is a really lovely instrument and will last year’s to come having been thoroughly cleaned internally and externally with a full professional service.
A good investment and very nice instrument.
Cosmetically 96% perfect and 100% operationally. ”
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Sequential Circuits Pro One

“Sequential Circuits Pro-One 80’s Vintage Classic Monophonic Synthesiser Synth. Condition is Used.
This rare original boxed beautiful example of the super classic monophonic synthesizer has been fully serviced by Cyberwave EMS , the keyboard has been re-bushed and thus plays as new. It was stored in its original box since purchased back in the 1980’s.
It is in as new condition and comes complete with the original user manual and cardboard box, I very much doubt you will find another like it which hasn’t been fully refurbished etc…
It is a good investment and an excellent instrument.
I would rather not risk posting it out and would prefer collection in person if possible. Please ensure that you have the money to make a full prompt payment before placing bids.Thank you.” Click here to search for synths on eBay

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Sequential Circuits Pro One

“Sequential Circuits Pro-One 80’s Vintage Classic Monophonic Synthesiser Synth. Condition is Used.
This beautiful example of the super classic monophonic synthesizer has been fully serviced and plays perfectly. It was stored in its original box since purchased back in the 1980’s.
It is in as new condition and comes complete with the original user manual and box, I very much doubt you will find another like it which hasn’t been refurbished etc… ”
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Sequential Circuits Pro One

“Sequential Circuits Pro One Keyboard Synthesizer. Condition is Used.

Membrane style keyboard, which triggers less reliably than the j-wire style. Triggers reliably via the CV input as is, or google “sequential circuits pro one membrane keyboard” to see a variety of other methods/retrofits.

Otherwise, this classic analog synth is in great working condition!”
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Sequential Circuits Pro One

“Sequential Circuits Pro-One 80’s Vintage Monophonic Synthesiser.

Please read carefully ;

I bought this synth completely refurbed it is very tidy however a few of the keys are now not triggering and will need to be serviced.

Any buyer is welcome to try the synth but it will be sold as seen I have tested it out and to my knowledge there are no other faults at all. I intended to get a service and keep it but now I’m needing funds to refurb my house so I decided to sell it as is.”
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Sequential Circuits Pro One

“Sequential Circuits Pro-One Vintage Analog Mono Synth Excellent condition. Everything works well. Has j-wire keyboard with replaced bushings. Sounds wonderful. Clean. Has minimal cosmetic wear. Selling as-is due to age. Manual and power cord included.”
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Sequential Circuits Pro One

” Sequential Circuits Pro One w/MIDI Vintage Analog Mono Synth. Excellent condition EXCEPT noise generator doesn’t work. Everything else works great. Has MIDI. Has j-wire keyboard with replaced bushings. Plays great. Sounds really great. Clean. Has a faint scratch on back and corner wear on one side. Otherwise, looks excellent. Selling as-is though. Manual and power cord included.”
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Sequential Circuits Pro One

“you are bidding on the synth pictured
from a private collection. has been sitting a long time
but in Great physical shape. all keys and functions are working well
some of the pots and switches and key contacts will need cleaning and normal service
I have not had this unit serviced, but will guarantee it to work as it should
faces up Very nicely as seen. wood sides are in very good shape.
dates to 1983. the keys are a bit clanky when triggered – I think they need a new felt strip inside
no major issues or problems”
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Sequential Circuits Pro One

“you are bidding on the synth pictured
from a private collection. has been sitting a long time
but in Great physical shape. all keys and functions are working well
some of the pots and switches and key contacts will need cleaning and normal service
I have not had this unit serviced, but will guarantee it to work as it should
faces up Very nicely as seen. wood sides are in very good shape.
dates to 1983. the keys are a bit clanky when triggered – I think they need a new felt strip inside
no major issues or problems” Click here to search for synths on eBay

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Sequential Circuits Pro One

“1x Sequential Circuits Pro One Vintage Synthesiser

In good working order, just had a service

Rebushed j-wire keyboard, plays nice and keys are level

Couple small chips on the front panel which are purely cosmetic

Missing both name badges, which it has been since I got it.

All time classic mono synth from sequential circuits. essentially a single voice prophet – and too wonderful for any words to do it justice! It also is the model with a Tibetan Buddha and chant* stencilled on the circuit board, for extra good vibrations!”
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