Sequential Circuits

“Very good condition and comes with Turbo CPU/MIDI, plus a top of the line Fatar keybed installed. this work costed around £450 just for the parts and so the synth is priced higher than the usual selling price to account for these highly functional upgrades.

The synth sounds perfect and was serviced when the MIDI and keybed upgrades were installed.

The Turbo upgrade gives full MIDI in and out functionality, as well as a number of other extended functions compared to the original.

The Fatar keybed replaces the often dodgy original keys with a top of the range set, the same as is used by manufacturers of new premium synths.

Note that this is a vintage piece of gear and as such does show expected signs of age cosmetically.” Click here to search for synths on eBay

“The Good: This vintage Pro One is in very nice shape and comes securely packed in a heavy duty keyboard case. I’ve owned this for about 20 years, and it’s spent much of the time inside the case, so it’s in nearly the same great condition as when I bought it. No sticky knobs or dents, the end wooden pieces look nice, and it comes with the original manual. There are a couple of small scratches on the underside.

The Bad: Though this is the preferred j-wire version of the keyboard, it does have an issue with repeating notes. Sometimes when you push down on a key, it triggers the note twice, and programming sequences confirms that is happening. It may be something simple to fix, like adjusting the j-wires, but after opening it up and seeing nothing obvious wrong, I decided not to mess with it. Personally, if I were keeping this I’d just replace it with this much better keyboard: https://techsmechsvintagesynth.com/home/tm-2-pro-one-keyboard-replacement-kit.html.

The Odd: You’ll notice a switch above the pitch wheel; this was a mod done by the prior owner, and I don’t even recall what they said the point was. As far as I can tell this just changes the pitch by one note, which could be used to slightly alter arpeggios or sequences. I’ve also included a photo of the board so you can see where it’s wired.

The other abnormality of this unit is the knobs; most of them were replaced with Moog knobs, which are bigger and much better I feel. Unfortunately I can only find 6 of the old original knobs, but I truly feel you’ll prefer the replacements. There are also a couple of CEM chips that came with it that I’ll also include, but I have no idea if they work or what they’re for, though I assume they’re filters.” Click here to search for synths on eBay

“You are bidding on a vintage Sequential Circuits Pro One monophonic synthesizer from the early eighties. The Pro One is famous for it’s snappy envelopes and is essentially one voice from the famous Prophet 5. With the step sequencer you can enter up to 40 notes/rests and play that sequence back while transposing it.” Click here to search for synths on eBay

“Sequential Circuits Pro One. Owned since new. Serviced by Synthrestore. Condition 9 out of 10. Some age related marks. Also has the original manual & guide sheet. ”
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“Sequential Circuits Pro One J-Wire Vintage Analog Mono Synthesizer Synthesizer in excellent condition. This is an amazing sounding vintage synth with two oscillators with cross mod sync. It also has a built-in sequencer. Very flexible modulation matrix. J-wire keyboard for easy cleaning, and they don’t wear out like the newer rubber keycap designs. All controls, functions, and keys work flawlessly. You won’t find one in better condition – it’s almost like new! ” Click here to search for synths on eBay

“Super clean, unmolested/unmodified original Sequencial Circuits Pro One model 100 !
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 One’s 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″ Click here to search for synths on eBay

“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

“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

“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

“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

“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

“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

“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

“Sequential Pro One analog Synthesizer

das Original aus den 80ern. Kein Re-Issue oder Clone

Das Gerät ist voll funktionsfähig und sehr gut erhalten.” Click here to search for synths on eBay

“Sequential circuits pro one with Midi a classic analogue mono synth.” Click here to search for synths on eBay