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Rare Chroma Polaris multi-timbral analog synth in near mint condition.  Rev 9 firmware with maxed out sequencer memory ( 4 X factory)

The Polaris is a highly under rated synth. It has a vintage analog sound along with the flexible MIDI implementation of a modern synth. This synth was ahead of its time obscured by the digital craze at the time. 

  • Full analog audio path 2 VCOs, VCF & VCA 
  • Uses the same CurtisCEM analog chips as the Oberheim Matrix 12
  • Semi-weighted keyboard capable of splits and layering
  • 8 individual instruments each with its own MIDI channel                       
  • 6 voices distributed to instruments with Dynamic Voice Allocation     
  • 12 sequences that can be looped and chained
  • All program parameters can be edited with sliders, no hidden edits, straight forward and simple. Many sliders have dual functions eg detune slider can be normal detune or beat frequency      
  • Uses MIDI Controller Codes to send & receive parameter edits. While a sequence is playing parameter changes can be played and recorded to a DAW
  • Responds to incoming MIDI aftertouch controls
  • Can convert pulse clock to MIDI clock or MIDI clock to pulse clock or internal clock to either one. Sequencer can be set to use internal clock, pulse clock or MIDI clock          
  • 3 MIDI channels out (good for controller) & 8 channels in
  • From external MIDI control it is possible to play the Polaris as a huge mono synth using up to 6 different programs played by 1 key from external controller This gives 12 VOCs, 6 VCFs, 6 VCAs, 6 LFOs & 6 Aux Envelopes for each note played (I provide documentation on how to do this)
  • Each program has memory for a 10 character name and the SysX implementation allows for communications with MIDI librarian apps. I have created a Librarian/Editor module for the MidiQuest app and SoundQuest has added it to their supported devices. The MQ Polaris program editor displays all parameter values which are updated in real time when edits are performed on the Polaris making it easier to edit from the Polaris panel. Note: The app is not included & I do not work for SoundQuest 

The Polaris I am selling is 1 of 2 that I own. I bought both new in the mid 80s. The MIDI implementation enabled me to create a 12 voice Polaris using the 2 synths. I used the 2nd Polaris (the one I'm selling ) as a slave controlling it with the 1st Polaris. As a result the faders and keyboard saw little use and are in excellent condition. With the exception of the membrane panel ( the original ones were made of materials that deteriorated over time, the new ones are of far better quality) both of these synths have been the most reliable of all the vintage synths I have owned. I took the first one (not the one I'm selling) on a 6 month international tour with absolutely no problems .

Even though this synth is in excellent condition certain parts in vintage synths deteriorate with age.  I have spent weeks on this project restoring this synth, replacing critical parts in particular caps and CMOS chips. I have meticulously cleaned all aspects of the synth and have completed all calibrations and adjustments. Also, I have spent considerable time programming a variety of programs and creating a Quick Start Guide. The Polaris Users manual is somewhat convoluted so the Quick Start guide includes a summary of the manual as well as tips on some of the more unusual functions.  


  • all pc boards have been thoroughly cleaned and inspected 
  • cleaned keyboard, sliders and lubricated PB & Mod levers
  • all jack inputs deoxidized and cleaned
  • replaced front panel membrane with new membrane
  • rebuilt power supply with new caps, voltage regulators & trim pots
  • replaced all caps on output board
  • On main PC board: 
  • replaced all trim pots,
  • replaced all electrolytic caps 
  • replaced all sample & hold caps (tuning, cutoff etc.) with 5% tolerance metal film caps
  • replaced Synth Board CMOS chips - 37 ICs in all
  • replaced all S & H op amps & wave shaping Op Amps - 18 ICs in all
  • new backup batteries
  • ⁃ Note: all parts are upgrades from original parts  
  • voltages and analog settings fully calibrated
  • all range adjustments performed
  • all calibrations tweaked after 20 hours of burn in / use

All the parts and work on this synth is exactly the same at what I have done on the other Polaris I am keeping for myself.  Note: As a trained, experienced technician I have worked on vintage synths for over 40 years.  I take meticulous care in all the work that I do with these units. 


  • Chroma Polaris
  • 2 Foot Switch Pedals
  • Power cord
  • Quick Start manual
  • Original owners manual
  • I will ship this in a custom, foam lined wood crate for safe transport

This is a rare versatile and amazing sounding synth.  It’s the closest thing to buying a new vintage synth with modern capabilities. I'm sure the buyer will be very happy with this one.

Note: The buyer is responsible for all import duties, taxes and local charges.

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Listeda year ago
ConditionExcellent (Used)
Excellent items are almost entirely free from blemishes and other visual defects and have been played or used with the utmost care.learn more
  • Chroma Polaris 64-Key 6-Voice Polyphonic Analog Synthesizer
  • Black
  • 1980s
Made In
  • Japan
Analog / Digital
  • Analog
  • MIDI Through
  • MIDI Input
  • MIDI Output
Key Size
  • Full Size
  • 6 Voices
Number of Keys
  • 64 Keys
Keyboard Action
  • Weighted

Retro Audio

Sechelt, Canada
Joined Reverb:2022

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