Pro One

“Audio Out
Audio In
Filter CV In
Gate Out
CV Out
Gate CLK In
CV In” Click here to visit listing on eBay

“Sequential Circuits Pro-One Vintage Analogue Synthesiser – Excellent condition and full working order, J-wire keyboard version. The classic analogue monosynth, with a huge range of sounds. Includes custom dust cover. The keyboard contacts were cleaned when I got it and it works fine, with occasional sticky contacts. It hasn’t been used for a while and would benefit from another clean if using the keyboard.” Click here to visit listing on eBay

” Sequential Circuits Pro One 37-Key Mono Synthesizer” Click here to visit listing on eBay

“Extremely rare Sequential Circuits Pro One Keyboard in good to very good condition. All original, not refurbished. Plays great.”
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“Fully functional Pro One in original condition with J-Wire keyboard. The synthesizer is in very good condition both visually and technically. In addition, I am giving a new and not yet installed TM-2 replacement kit (semi-weighted Fatar keyboard with mounting accessories) as well as Potikappen in the Prophet-5 look from the company. Techmechs Vintage Synth.”
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“WORKING CONDITION: Fair- Works about 90%. We cleaned the keyboard and exercised some knobs. Four of the keys are really sticky and tend to stay down when pressed, so they may need some mechanical adjustment. Seems like they’re all mostly engaging though. Some of the controls particularly the filter cutoff are a bit glitchy sounding. In all, this synth will need additional service besides cleaning and maintenance to get it to 100% Currently listed as in fair working condition.

PHYSICAL CONDITION: Very Good – There are some scuffs and dings around the synth. The keys are uneven and probably due for some new bushings, but otherwise, work and feel fine. All buttons, sliders, and knobs intact and ready for action. Overall, the physical condition is very good.

INVENTORY #49146

BRAND: Sequential Circuits

MODEL: Pro One

FUNCTION: Synthesizer

PRODUCT DESCRIPTION: This listing is for a Sequential Circuits Pro One 37-Key Mono Synthesizer

This item was part of Dennis Herrings’ studio production arsenal at his Sweet Tea and DTLA Recording studios.

SPECS:

Serial #9149” Click here to visit listing on eBay

“This needs a lot of work. Some keys trigger while others dont or have some contact issues. A wheel has broken off but can be bought and/or printed. This sale is As-is so treat it like you are purchasing for parts and anything else is a bonus. Turns on without issue. Great project for anyone that wants to replace the bushings, do some key work (def needed) and anything else that comes up.” Click here to visit listing on eBay

“Sequential Circuits Pro One Synthesizer Model 100 Sold AS-IS for restoration. It powers up. I am not familiar with these. I do not know history. I think it is from 1979. I assume the power on/off switch went out so the previous owner hardwired it on. The only way to turn it off on is plug/unplug. One key is higher than others. I opened it up and saw one pin on connector the 16 pin connector was broken off. (see photo) I may have done it opening it up. Those are the only things I noticed. Sold as-is for repairs.” Click here to visit listing on eBay

“This is the J-wire version which Is supposed to be the better of the two. The keys like to double trigger anyways. It takes a bit of work to stay in tune, but hey it’s 40 years old. I made a whole album with this beast. If you wanna listen let me know. It sounds HUGE” Click here to visit listing on eBay

“For sale:

Sequential Circuits – Pro One – Rare Vintage Analogue Synthesizer

Fully serviced by Cyberwave EMS synth restoration in 2022. The synth is in excellent cosmetic condition, perfect working order and plays beautifully. Cyberwave, who have serviced hundreds of Pro Ones, said it was one of the best condition and cleanest Pro Ones they’ve ever seen!

The serial number is #4371 which makes it the most desirable of the Pro Ones produced as it’s the j-wire version (below #8500) which is more stable and easier to repair and also features the non-circuit board mounted power supply (above #1500).

It also comes with a custom flight case that protects and fits the synth perfectly.” Click here to visit listing on eBay

“Sequential Circuits PRO ONE Analog Synthesizer 37 key Keybed And Housing. No synthesizer just the keybed and case in as-is condition. I believe the keys were working before the synth was removed but have no way to check. ” Click here to visit listing on eBay

“Excellent condition for its age. Has been completely gone through recently by a well known record producer / tech savvy. Only played occasionally and covered in the clear plastic cover when not used. Few cosmetic marks/blems as seen in the photos. Everything works as it should. All functions works.” Click here to visit listing on eBay

” Aficionados will recognise this as a relatively early example with the “J-wire” keyboard. Apparently this is easier to repair than the later version.

I have owned this for nearly 40 years and never gigged it. After a long period of non-use I was pleased to find that everything appears to be working, although the keyboard is quite “clicky” and I noticed occasional re-triggering or slurring of notes. So you can have fun with it right away but for serious work I would strongly recommend a service. Cosmetically it is fine apart from traces of marker pen applied by me for security purposes, back when iI was living in a dodgy part of town. See the photos for details. As you will see, all the knobs and switches are present and correct.”
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“I have owned this for nearly 40 years and never gigged it. After a long period of non-use I was pleased to find that everything appears to be working, although the keyboard is quite “clicky” and I noticed occasional re-triggering or slurring of notes. So you can have fun with it right away but for serious work I would strongly recommend a service. Cosmetically it is fine apart from traces of marker pen applied by me for security purposes, back when iI was living in a dodgy part of town. See the photos for details. As you will see, all the knobs and switches are present and correct.” Click here to visit listing on eBay

“A used Musical Synthesiser that is in a great condition. The item is used and does have some wear and tear. The synthesiser has recently been fitted with a new plug and comes complete with the flight case and wooden stand sides. Every key does work.

The item is sold as seen. ” Click here to visit listing on eBay

” For sale, Sequential Circuits Pro One. Everything works but some knobs could probably use a cleaning. Comes from a good owner with several nice features and improvements:

S/N 100-0028, 1981
Original Manual
Custom Road Case by Emperor Cabinets in Chicago
Dust Cover
MIDI add-on
J-Wire keyboard
Prophet 5 knobs instead of original knobs, quite snazzy
Attached power cable replaced with standard 3-prong “PC” adapter, will include cable

Due to the age it is being sold as-is.”
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” For sale, Sequential Circuits Pro One. Everything works but some knobs could probably use a cleaning. Comes from a good owner with several nice features and improvements:

S/N 100-0028, 1981
Original Manual
Custom Road Case by Emperor Cabinets in Chicago
Dust Cover
MIDI add-on
J-Wire keyboard
Prophet 5 knobs instead of original knobs, quite snazzy
Attached power cable replaced with standard 3-prong “PC” adapter, will include cable

Due to the age it is being sold as-is.” Click here to visit listing on eBay

“sequential circuits pro 1 Full Kenton MIDI Spec and new keyboard.

I’ve owned this unit for 14 years about and when I had Kenton fit the midi retrofit the engineer said it was in exceptional condition inside and out.

I have also fitted a new Techsmechs Fatar keyboard … I have a Nord stage 3 compact with waterfall keys and it’s a Nord and great to play but this has been said and it’s easily as good …

.. ~~~Nords are unquestionably top notch instruments, but several times I’ve seen the opinion expressed that the Fatar TP40 and TP100 keybeds feel better on other instruments than they do on Nords that have the same actions, and I tend to agree. ~~~🤷🏼‍♂️

So it has a Fatar keyboard and this is a dream to play ..like butter no more clickety clack keys and poor contact issues …

But I also have it’s original Keyboard boxed and is included.

The nobs have also been replaced with Techmechs … and there are no duff spots or crackles on the pots and it all tunes and lines up properly.

It also comes with the red swan flight case but being such a delicate item I would advise collecting or a very careful courier organised by you ! ” Click here to visit listing on eBay

“This listing is for one used original vintage Sequential Circuits Pro~One synthesizer. I bought this used in 2011, it had been previously stored in an attic for years. It has lived in my home studio ever since.

I had the oscillators tuned and power plug replaced by a professional. I replaced all key bushings and cleaned the J-wire myself. It is in excellent condition. Please scrutinize the pictures. Everything works flawlessly. The keys will double trigger, but that’s j-wires for you. Clean them and they work great until a spec of dust rests on one. ;-)”
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” I bought this over 10 years ago – and it has been in storage. I have therefore had it serviced a few months ago to ensure it functions properly.

I can’t really grasp the concept of envelope generators and oscillators etc to make good use of this machine – I much prefer the pre-sets which I have a plenty on the Korgs, Roland and Alesis keyboards in my arsenal. So rather than put the machine back into storage, I have decided to sell it – hopefully to someone who understands analogue synths and can put it to optimum use. ” Click here to visit listing on eBay

“Early 80s Sequential Circuits PRO 1 Analog Synthesizer + Manual.

I’ve had this synth for about 5 years and I just don’t get enough use out of it anymore.

It’s due a service as several of the pots crackle and need a clean.

It’s also fitted with the less desirable membrane key board which needs upgrading (anyone that’s familiar with Pro Ones will know exactly what I mean). For this reason a few of the keys no longer work. However, if you are planing on using this synth via CV, like many people do, this doesn’t present any problems.

The service that needs doing is reflected in the price that I am asking.

Apart from the above it works exactly as it should. It’s also in fairly good aesthetic condition for a synth of its age (please see pictures).

I did consider servicing it and relaying the keyboard myself, however I have neither the time nor the desire to do so. ” Click here to visit listing on eBay

“Excellent condition for age.” Click here to visit listing on eBay

“Sequential Circuits Pro One

Recently installed brand new Fatar keybed (that which you find on the OB6, Prophet 6)

it has a great feel, lovley to play.

Recently serviced all checked, its 100% functioning and working like it should.

Will pack bullet proof, with priority tracking.” Click here to visit listing on eBay

“Something very special. Fully customised Pro-One, featuring the following:

– Fully custom walnut casing 

– Kenton midi kit 

– Brand new fentar keyboard 

– Pro 5 pot and button upgrade

– Fully serviced 

All of these upgrades cost well over £1,000. What you’ve got is an absolute classic updated for the modern producer and looking gorgeous.

I will guarantee the item against functional defects for 3 months. Due to nature of the item I will only repair any defects subject to fair use.” Click here to visit listing on eBay

“Early 80s Sequential Circuits PRO 1 Prophet One Analog Synthesizer + Manual.

One owner from new with original owners manual.

In full working order see condition in photos.

Collection only.”
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” Sequential Circuits Pro-One Vintage Analogue Synthesiser – Excellent condition and full working order, J-wire keyboard version. The classic analogue monosynth, with a huge range of sounds. Includes custom dust cover. The keyboard contacts were cleaned when I got it and it works fine, with occasional sticky contacts. It hasn’t been used for a while and would benefit from another clean if using the keyboard.” Click here to visit listing on eBay

“sequential circuits pro one.

Really nice fully working j wire example.

Never toured/gigged” Click here to visit listing on eBay

“1980s Sequential Circuits PRO ONE synthesizer Spares Or Repair.

Been stored for ages

No lead

Please see photos

Sold as seen” Click here to visit listing on eBay

” Sequential Circuits Prophet 2000 Keyboard Sampler

Reluctantly selling my Prophet 2K, the classic 80’s sampler that along with the Ensoniq Mirage ushered in semi-affordable studio-grade sampling for a much broader range of musicians, and helped give birth to House Music, and Electronic music as we know it. Serviced a year ago (I’ll include the receipt, £160 spent with a top tech) and not used much since, I just don’t have the space to set it up these days, so it’s annoying my wife in the spare room. Almost worth keeping for that reason only but best to try to score some brownie points before Christmas.

It’s fitted with the excellent 2x Memory Expansion by Synthechnics (cam reform Portugal, another £100 or so), which is a modern reliable clone of the original SCi one. Membrane buttons, wheels, dials and all keys work great, with display bright and clear. In fact the tech thought that the tact switches under the membrane may all have been replaced at some point pre-me, which is a handy bit of future proofing I didn’t realise (although they always felt surprisingly good). Quite a few age-related marks and scratches here and there on the bodywork, and that’s just a bit of old tape residue on the back corner that may well come off with a bit of perseverance, but no scary damage, just a nice honest example. It comes with the UK power lead, plus the original Operation Manual, which is a rare thing, a chunky ring-binder file. Latest/last OS version chip installed too.

These are coming up for sale less and less often, partly due I’m sure to videos by Espen Kraft and others showing what these are capable of, and what they can add in a modern studio setting. So a serviced one with memory expansion and the original manual file is a rarity. I can’t see another P2K available either on reverb or on here right now in the UK, or anywhere in the world for that matter.” Click here to visit listing on eBay

“model # 100, serial # 2330

This Pro One is in perfect working condition. It was calibrated and it’s J-Wire keyboard was rebuilt several years ago. I bought this synth in 1990 when people were dumping analogue synths. Since that time it has been taken very good care of. When not in use it is always covered. This Pro One is missing two of its four rubber feet. This unit was in a stand so it was never an issue for me. I am selling this unit to fund purchasing some eurorack synths. I own another Pro One I bought in 1981 and a newer Behringer Pro One. ” Click here to visit listing on eBay

“This Pro One is in perfect working condition. It was calibrated and it’s J-Wire keyboard was rebuilt several years ago. I bought this synth in 1990 when people were dumping analogue synths. Since that time it has been taken very good care of. When not in use it is always covered. This Pro One is missing two of its four rubber feet. This unit was in a stand so it was never an issue for me. I am selling this unit to fund purchasing some eurorack synths. I own another Pro One I bought in 1981 and a newer Behringer Pro One. ”
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“Something very special. Fully customised Pro-One, featuring the following:

– Fully custom walnut casing

– Kenton midi kit

– Brand new fentar keyboard

– Pro 5 pot and button upgrade

– Fully serviced” Click here to visit listing on eBay

“Selling my Pro One which I have owned since new. Everything works. This has the J wire contacts keyboard, not the unreliable membrane switches. This is pick up only.”
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“Selling my Pro One which I have owned since new. Everything works. This has the J wire contacts keyboard, not the unreliable membrane switches. This is pick up only.” Click here to visit listing on eBay

“sequential circuits Pro1.

Recently serviced by Jim McKenna , owner of Singing Cat ,

I’ve had this for almost 30yrs , never been gigged and I don’t smoke ,

It’s as crisp as the day I got it

Should have mentioned , This 1981 board is the preferred Jwire synth , much more reliable and easier to maintain,,,” Click here to visit listing on eBay