Sequential Circuits

“For sale: A gorgeous example of the classic Sequential Circuits Pro One. Fully restored around 8 years ago by the famous Kent Spong on behalf of RL Music, it is almost blemish free apart from one or two minuscule marks. It was fully serviced only a week ago by Ben at Cyberwave Studios. Cleaned inside and out the j wire keybed has been cleaned and re set. The machine has been tuned and calibrated and a new noise generator installed. The Wooden end panels are undamaged and the switches and knobs are smooth and solid. It really is an absolute joy to play and sounds incredible. In its current condition you are looking at years of big bass, silky leads, punch and grit before you will need to have it serviced again. I really will be sad to see it go. ” Click here to visit listing on eBay

“This is a Sequential Circuits Pro One synthesizer.
I am including a DI box in the package (as this eliminates audio hum).

The main circuit board was built in April 1982.
The serial number on the board and the one on the casing don’t match, which would suggest to me that the synth is a combination of two previous synths.
I have made a few improvements / fixes to the synth since I bought it:
A complete clean inside and out. All switches have been cleaned as have all key contact points.
Some capacitors have been replaced.
An internal ribbon has been replaced (bought from Wine Country Productions Inc).
I have bought wooden end cheeks for the synth, since these were missing.
I have also replaced a mod wheel (which was broken) with a clear acrylic wheel.
There is audio hum. Apparently, this is a very common feature of the Pro One and is due to a ground loop (an original design oversight).
The DI box eliminates the hum, and this is why I am providing the DI box with the synth.
I’ve tuned the synth using the variable resistors (pots). The tuning is pretty good across the keyboard, but will no doubt need readjusting from time to time.” Click here to visit listing on eBay

” Up for sale is a highly cool Sequential Circuits Pro One with the proper J Wire Keybed. NOT the inferior membrane keybed.

As you can see this classic beast of a synth has been properly cared for all its life. Never abused or mistreated : ) It looks amazing and it plays amazing. There is nothing like a real Pro One. Basses, Leads, Efx, Swells and more… this synth has just a jawdropping sound. Perfect addition to any synth freaks collection.

It all works great, plays great and is properly tuned and scaled across many octaves. But as you’d know if you play, collect and use synths of this era. It MAY or may not need a scaling / calibration after being in transit.. just stating for full disclosure. THIS 40 year old electronic synthesizer is not applicable for returns for any reason. ” Click here to visit listing on eBay

“Up for sale is a highly cool Sequential Circuits Pro One with the proper J Wire Keybed. NOT the inferior membrane keybed.

As you can see this classic beast of a synth has been properly cared for all its life. Never abused or mistreated : ) It looks amazing and it plays amazing. There is nothing like a real Pro One. Basses, Leads, Efx, Swells and more… this synth has just a jawdropping sound. Perfect addition to any synth freaks collection.

It all works great, plays great and is properly tuned and scaled across many octaves. But as you’d know if you play, collect and use synths of this era. It MAY or may not need a scaling / calibration after being in transit.. just stating for full disclosure. THIS 40 year old electronic synthesizer is not applicable for returns for any reason. ” Click here to visit listing on eBay

“For sale: A gorgeous example of the classic Sequential Circuits Pro One. Fully restored around 8 years ago by the famous Kent Spong on behalf of RL Music, it is almost blemish free apart from one or two minuscule marks. It was fully serviced only a week ago by Ben at Cyberwave Studios. Cleaned inside and out the j wire keybed has been cleaned and re set. The machine has been tuned and calibrated and a new noise generator installed. The Wooden end panels are undamaged and the switches and knobs are smooth and solid. It really is an absolute joy to play and sounds incredible. In its current condition you are looking at years of big bass, silky leads, punch and grit before you will need to have it serviced again. I really will be sad to see it go. ” Click here to visit listing on eBay

“Sequential Circuits Pro One Vintage Synthesiser.

This Pro One is in great condition, with only the handful of minor blemishes that are to be expected on a vintage instrument of this age. I’ve done my best to picture these.

The keyboard and all other features work perfectly.

Unfortunately the two labels (Pro One & Sequential Circuits) have been lost over the years, but otherwise everything is as it should be.” Click here to visit listing on eBay

“Sequential Circuits Pro One Analogue Synthesiser. In working condition with a made to measure flight case and original manual. There is one potentiometer knob missing. Recommended to have it serviced to get a better action on the keys.” Click here to visit listing on eBay

“Absolutely stunning boxed Pro One, Rev 1.2 dated 12th June 1981 on the main board, so just turned 40 years old. In breathtaking condition with only very minor age related wear, has been kept in it’s box for many years and looks almost like it just came out of the factory. All original dials, wood ends and badges etc., and the original box even has the polystyrene ends present and complete. I can only find one other boxed example sold worldwide in the last 5 years, that was in the US/Canada, so this is a really rare piece of synth history, not just this side of the Atlantic but anywhere worldwide. Needless to say the Pro One, along with the Minimoog Model D, are the mono synths that shaped modern music

Serial number is in the 5000’s which is the absolute sweet spot for a Pro One, signifying the preferred J-Wire keyboard and the case-mounted rather than board-mounted power supply (you want one with a serial number between 1500 and 8500 ideally, this is bang in the middle). Has recently been carefully cleaned inside and out, keybed was removed and cleaned, a full set of new rubber key bushings from Vintage Vibe in the US have been fitted, keys removed and individually cleaned (the white ones are super-bright, no major discolouration), dials removed and individually cleaned, all pots and switches treated with DeOxit, and the wood ends lightly fed with a premium Danish Oil to nourish the timber and bring out the grain. The odd light evidence of age and use of course, the ends and shiny bits inevitably pick up small signs of wear, but it’s hard to imagine there being a better example out there. Hasn’t been over restored, just sympathetically refurbished. It’s looks amazing and sounds incredible.

The main circuit board shows off the classic markings you expect to see in a Pro One and original Prophet 5 etc., including the Hindu god ‘Vishnu’ stamp, the beautiful Rev 1.2 and ‘toadstools’ marks flowed on in solder, and the hand written calibration notes and build date. The boards in these are a real work of art. I have many more pics than the 12 included here, so if you need more or wish to view please ask.” Click here to visit listing on eBay

“This Sequential Circuits Pro-One Model 100 is remarkably well-preserved, with nigh flawless silkscreened graphics and all original knobs and switches intact. The wood sides show sparingly little wear and the serial number and original factory warranty stickers are intact on the back of the enclosure.” Click here to visit listing on eBay

“Incredible monosynth. I bought this one in 2019 and have made a lot of great tracks with it! I’m now making a different style of music so I don’t need as many analogue synths anymore.

Selling it for the same price I bought it for (so no offers please!)

A previous owner upgraded it with midi, and it comes with a great flight case.” Click here to visit listing on eBay