MAX, Sequential Circuits @ 01 March 2018, Comments Off on Sequential Circuits MAX

“Up for auction is a vintage Sequential Circuits MAX Synthesizer keyboard. This unit is working and seems to have most all functions in place and operative. I’m guessing the unit has 6-note polyphony, and it sports a rudimentary onboard sequencer – ‘Start’ button is missing, and I didn’t bother to try and test the sequencer function as I doubt it would stack up against, well, anything made after 1982. You get basically 7 banks of 10 sounds, and apparently the only way to ‘deep edit’ the sounds is via computer. (Note that by progressing further into editor mode you will be officially flirting with full-blown geekification.) I can’t even dare to guess what hoops you’d have to jump through to get a modern computer to communicate with MAX, clearly a throwback to the heady infancy of financially accessible analog synthdom. Perhaps there are generic editor programs out there…? That said, there are a handful of onboard presets that are recognizable, and I daresay that in bank 4 (40-49) there is at least one startling TB-303 soundalike. MAX appears to be responding to MIDI in Omni mode, though Poly mode is selectable. External Pitch and Mod wheels are recognized, but suspiciously, Volume is not. ‘Tune’ button is missing, but the unit sounds like it powers up at concert pitch. Back panel power jack is looking for 8 Volts AC / 800ma – I am including a 10V adapter that seems to work fine, but I would suggest being on the lookout for a proper 8V / 800ma adapter. Cosmetically, the unit is in pretty good shape, looking good for its age. I cannot test every single function on this synth, and I have tried to describe it as accurately as possible – I am selling it As-Is and As-Described.” Link

MAX, Sequential Circuits @ 22 February 2018, Comments Off on Sequential Circuits MAX

“SEQUENTIAL CIRCUITS MAX synthesizer, no power supply = UNTESTED, 1 button is missing, LEFT SIDE PANEL is CRACKED – needs to be serviced.” Link

MAX, Sequential Circuits @ 14 December 2017, Comments Off on Sequential Circuits MAX Project Machine

“Powers on and goes through the normal boot / oscillator tuning sequence, but after that I am unable to get any sound out of it. It could be the keyboard, it could be the voice chips, or it may just be in some midi remote mode that deactivates local control. If you are good with electronics I am sure you can get this sucker working again. the unit is missing the little rubber button for the “sequencer start.” i wouldn’t use the internal sequencer anyways and i doubt you would either. Includes power supply and a beat up hard shell case. cosmetic condition is not too bad. see pics!” Link

MAX, Sequential Circuits @ 12 October 2017, Comments Off on Sequential Circuits MAX

“Sequential Circuits MAX analog synthesiser with original uk power supply and manuals. Some keys don’t work well and a few buttons and voice chips are missing.” Link

MAX, Sequential Circuits @ 29 June 2017, Comments Off on Sequential Circuits MAX

“NO RESERVE!! FREE SHIPPING!! (Continental United States – lower 48) This Sequential Circuits Max 620 is a little rough around the edges cosmetically but solid. The metal has some rust on it, one of the keys is broken off about halfway through and the #2 sound select button is missing (all blemishes photographed). The keyboard itself works great! Includes the Max Midiguide and the power adapter. Comes exactly as photographed, See photos for further details and visual description ” Link

MAX, Sequential Circuits @ 09 February 2017, Comments Off on Sequential Circuits MAX

max “You are bidding on the rare and vintage Sequential Circuits MAX synthesizer. I do not have the power cable and have not tested this keyboard- sold as is. ” Link

MAX, Sequential Circuits @ 02 February 2017, Comments Off on Sequential Circuits MAX

scimax “Has light wear/scratches from normal usage. I do not have the power cable and therefore cannot test the keyboard. Sold as is/for parts” Link

MAX, Sequential Circuits @ 20 October 2016, Comments Off on Sequential Circuits MAX

max “This is a very rare and hard to find MAX MIDI Sequential Voice Expander keyboard. The piano is in excellent condition and has only been used in a home studio setting, the piano has very minimal light scratches that are very hard to see. It still works like it is brand new and comes with the original owners manual, power cord, as well as a very nice carrying case.” Link

MAX, Sequential Circuits @ 01 September 2016, Comments Off on Sequential Circuits MAX Project Machine

sci_max “Vintage Sequential Circuits Synthesizer MAX 620 Midi Voice Expander Peripheral Moog MULTI-TIMBRAL ANALOG SYNTHESIZER

Highly collectible and sought-after vintage synthesizer from 1984. Ultra rare and hard to find. See actual photos.

Unit powers on. Red light shows on Track 1 and the number 1 appears on the middle display (as shown).

Tested with a universal adapter (not included). No further testing. Selling AS IS. No returns. Cosmetically in great shape. Please look at the detailed photos.

Very low serial number: 00226”

MAX, Sequential Circuits @ 01 September 2016, Comments Off on Sequential Circuits MAX

sci-multi-trak “Sequential Circuits Multi-Trak synthesizer in great condition with original power supply, operation manual, midiguide, and even the original cassette tape with the factory programs! Functions and programs fine, sequencer, arpeggiator, chorus, etc. all work. However not all 100 factory pre-sets are currently loaded – you can re-load these by purchasing a .wav file from Wine Country Sequential for $20. Or program all of your own sounds! I have not tested all of the 6 outputs or every possible function of this keyboard but I have used it live and for recording and the functions I have used work.” Link

MAX, Sequential Circuits @ 01 September 2016, Comments Off on Sequential Circuits MAX

max “For sale is a vintage, 1984 Sequential Circuits Max (Model 620). Great working condition and no major cosmetic flaws.”

MAX, Sequential Circuits @ 18 August 2016, Comments Off on Sequential Circuits MAX

nax “We recently purchased this very hard to find very collectible Synthesizer from a going out of business music store auction. I don’t have the power supply to test this unit. Please assume because I have not tested this that there is most likely something wrong with it and will need work. Unit has scratches and worn paint. All the keys have spring to them and none feel stuck but that does not mean they work as i have not tested it. Some of the soft push button pads seem loose. Being sold untested – as-is – nothing is guaranteed to work – for parts or repair – no returns” Link

MAX, Sequential Circuits @ 19 May 2016, Comments Off on Sequential Circuits MAX

For sale is a very rare and very underrated Sequential Circuits MAX Synthesizer. These were released in 1984 as a way to appeal to the home recording market. They were originally intended to be controlled via midi by a Commodore 64 computer with special software. They could be considered the little brother of the SCI Six-Track due to the fact that they are very similar in terms of voicing and features, but the MAX only features 20 user patches and 80 presets.

This things a beast and would be perfect for any home or professional studio. The presets are all awesome from the lush strings to the phat analog basses. It even features several weird SFX sounds. With modern technology the custom user patches can now be controlled manually by mapping midi CC values to an external controller.

***The basic functions if the unit have been tested and to the best of my knowledge it is in full working order. The unit powers on and all presets and the sequencer work. The unit is properly sending and receiving midi messages. I was able to create a few custom user patches using a Synlib editor and they worked great!

***Cosmetically the unit is in fantastic condition for its age. There is some very light rust of the metal case and a few scuffs and scratches but overall it looks great. Take a look at the pics and see for yourself

***The sale will include an 8VAC power supply, which from what ive read online is very hard to find. The adapter is not the orginal but is the correct voltage and polarity. The unit calls for 800mA this supply gives 1000mA which is more than enough for the unit to draw. ” Link

MAX, Sequential Circuits @ 12 May 2016, Comments Off on Sequential Circuits MAX

max “Condition: vintage midi voice expander circuits max 620 keyboard. Parts or repair only. Not tested. No power supply included. Please inspect pictures carefully

Note: if it’s not in the picture it’s not included unless it’s stated that it is. ” Link

MAX, Sequential Circuits @ 17 December 2015, Comments Off on Sequential Circuits MAX

sci_max” I’m the original owner of this synth. It’s been sitting in a closet for years. In good, working condition but does require replacement of one rubber button cover (which can be found on the web) and a power supply. Used a 3rd party adapter and worked fine. Keys are in great shape.” Link

MAX, Sequential Circuits @ 10 December 2015, Comments Off on Sequential Circuits MAX


Sequential Circuits MAX Lovingly Refurbed by Syntronics. Works Great! Really sounds great. ALL 6Voices using CEM3394 IC’s work.

Original Power supply.

The graphics are really good but because of the metal chassis there are dotted rust spots all over but it’s not objectionable in my eyes. I cleaned all the keyboard contacts including all the function buttons. No need to press hard. ” Link

MAX, Sequential Circuits @ 26 November 2015, Comments Off on Sequential Circuits MAX

sci_max “Hello, thanks for looking! Here’s another legacy item from the vaults – a Sequential Circuits MAX keyboard. It has a built-in six-track recorder, 80 preloaded sounds (the strings and brass in particular are pretty good), fairly primitive MIDI capability, and it comes with the ORIGINAL POWER SUPPLY. It was tested and powers up just fine, going through the warm-up and tune-up processes, even playing the demo song. Now the caveats: the box and docs are long gone, it could use a good cleaning inside and out (opening stuff like this up gives me the creeps), and the high-B key doesn’t seem to produce a note (could be from an evil dust bunny lurking inside). For these reasons, I’m obligated to sell the unit for parts/not working – but if you’re fairly savvy with stuff like this, you might be able to restore it to full functionality. The sucker is heavy, so I’ll pack it for an industrial-strength journey to wherever you want it shipped. Because of the issues, it’s being sold AS-IS, with no returns accepted.” Link

MAX, Sequential Circuits @ 19 November 2015, Comments Off on Sequential Circuits MAX Project Machine

sci max “Sequential Circuits

MAX model 620

Description: . comes as seen. please see all pictures. does NOT includes 8V AC power adapter.

Condition: Powers on and all keys working good. seem to have all it’s sounds and seems to be pretty much working correctly. I do not have the exact power supply for this unit so I am not sure the backround noise is from the power supply or from the synth. you can watch the video below and see how this unit works. you can hear the backround noise. when you hit the TUNE button the noise gets louder and it goes through a tuning cycle. all keys do work but some seem out of tune. I have not serviced this unit and it is older and will need some service and cleaning for optimal performance so I will have to sell this keyboard AS-IS – No returns. there is no overt damage or broken keys. ” Link

MAX, Sequential Circuits @ 05 November 2015, Comments Off on Sequential Circuits MAX

max “The Sequential Circuits Model 620 Synthesizer Max, Midi Voice Expander, is in good condition and fully functional. The MAX has a chipped right end cap but, otherwise, is very clean. All buttons, sliders, and outputs work fine, no issues. 30 day dealer wnty.” Link

MAX, Sequential Circuits @ 15 October 2015, Comments Off on Sequential Circuits MAX

max“This synth is really cool. It does have scratches and bumps and may be in need of service but it powers up and seems to be working okay. The keys are intact and not damaged other than a scratch or two. These are built very well as you know. Kinda hard to find this one though it is unfortunately not in perfect shape. It will take attention and a proper cleaning. Probably made early 80’s.” Link

MAX, Sequential Circuits @ 04 September 2015, Comments Off on Sequential Circuits MAX

sci max” This board appears to be in good condition cosmetically for it’s age. I have no way of testing it because I do not have the power supply for it. This auction includes only what is pictured. As crazy as it sounds, if anyone who is really interested in the board has a power supply they would send to me, I can test it and then send the supply back. The reserve on the board is 100.00 ” Link

MAX, Sequential Circuits @ 04 June 2015, Comments Off on Sequential Circuits MAX

sci_max“The Sequential Circuits MAX is is in good condition and fully functional. The keyboard has various minor scratches but looks like the pictures depict, clean for its age. The volume knob is not original. Adapter incl and a 30 day dealer entry. ” Link

MAX, Sequential Circuits @ 14 May 2015, Comments Off on Sequential Circuits MAX Project Machine

max “sequential circuits MAX Synth. Stopped turning on for some reason. probably an easy fix. one or so of the voices might not work but these chips are cheap on ebay. i know zens electronics charges 30 pounds to change chips in london. Most likely cheaper in other smaller cities. Original Power Supply. i haven’t used this in awhile so i’m selling as is. Its been kept in a dry studio its whole life with me. i take care of my equipment.” Link

MAX, Sequential Circuits @ 26 March 2015, Comments Off on Sequential Circuits MAX

max ” looks a bit scratched up but works perfect. missing a rubber button but still works if you push it with your pinky finger. i lost the charger. COMES WITHOUT CHARGER. ” Link

MAX, Sequential Circuits @ 26 March 2015, Comments Off on Sequential Circuits MAX

sci_max “The unit for sale shows signs of wear on its cover, as evidenced in the photos. There is a large scratch on the center of the metal cover on the Sounds section. The unit powers up when turned on. All keys function and respond (see below), and all sound sequences and settings appear to work. However, as the sounds cycle through the six tracks, whichever key is depressed during track 5 utters no sound. I do not know if there is a hardware issue or something wrong with the software. The position of Track 5 differs by the sound setting, so the issue is not set on any specific key. But when playing up the scale, at least one key in every register will not sound. There may or may not be a fix to this, but any potential buyer should be aware of this issue. There are still numerous unique analog sounds to sample from, and it is a functional MIDI keyboard as well.” Link

MAX, Sequential Circuits @ 15 January 2015, Comments Off on Sequential Circuits MAX

sequential circuits max“In full working order and great cosmetic condition” Link

MAX, Sequential Circuits @ 19 June 2014, Comments Off on Sequential Circuits MAX

“Sequential Circuits Max Analog poly preset synth. 6 VCO’s and 6 VCF’s – one per voice. These don’t show up very often, so get it while you can. Pretty cool synth, the presets are very awesome & has a very warm sound. Can be edited via mac or pc editor also. Some of the lettering is fading a little but still readable. Other than that this unit is in excellent condition.” Link

MAX, Sequential Circuits @ 29 May 2014, Comments Off on Sequential Circuits MAX

“This is a rare Sequential Circuits Max analog synthesizer + original 8VAC power adapter, operation manual and midiguide.
The synth is in good working condition.
The only thing I noticed is that the included power adapter seems to work better when connected straight to the wall. When connected to a power strip, it doesn’t make a contact unless the plug is pulled out of the strip a little bit.
The synth has 80 built in presets that are divided into groups – Organ, Brass, Strings/woodwinds, Keyboards, Bass/percussion, Synthesizer I, Synthesizer II, Special Effects. There are also 20 presets that can be programmed via an external computer.
The built in preset parameters can only be changed using an external computer and compatible software and you won’t be able to access the programmed presets (80-99) unless you programmed these presets using the software.

Originally, Sequential Circuits sold a Commodore 64 software called Model 920 that was designed to edit the Max parameters, however, there are few PC and MAC softwares that you can use these days. I managed to edit the synth parameters using a software called ‘ctrlr’ with the downloadable Sixtrak panel. Ctlrlr is a free software and it’s available on

Cosmetically, it has signs of wear here and there, some scratches and marks, a small paint chip next to the ‘2’ button (see photo), some engraved letters on the back of the synth (see photo), overall in nice vintage condition. Please refer to photos for condition.” Link

MAX, Sequential Circuits @ 09 January 2014, Comments Off on Sequential Circuits MAX

“This is a used Sequential Circuits Max synthesizer model CM620A serial number 620 01266 from August 1984. It is in good working order and as far as I can tell everything is working. The only two issues of note are that the volume pot is ‘dirty’ and makes a scratching sound when changed, this could probably be fixed easily, once the volume is set the static sound goes away. The other issue is that the original power supply is a little picky about which outlets it likes, I find it works best when plugged into the wall as opposed to a power strip. Usual wear and tear from 30 years is obvious in the pictures. Biggest visual issues is a ding on the cover near the 2 button (see photos) and the CALIF E0096668 scratched in the back of the unit.” Link

MAX, Sequential Circuits @ 28 November 2013, Comments Off on Sequential Circuits MAX

Hello, I’m selling a used Sequential Circuits Max Analog Synth!!!
Everything on this Synth cosmetically looks great other than a few minor scratches on top and two buttons missing.
There’s no box, instructions. user guide or power adapter with this item.
This item needs work but nothing major!
I was told by a electronic specialist that it has a small short and may need someone to clean the overall analog synthesizer.
This is a rare analog synthesizer with a great sound made by one of the world renowned synthesizer companies Sequential Circuits!
This is a “AS IS” purchase no returns but its a great synth and project for the right person!” Link

MAX, Sequential Circuits @ 31 October 2013, Comments Off on Sequential Circuits MAX

“Sequential MAX,

hier verkaufe ich einen wirklich ausgefallen und seltenen Synthersizer!!

Er ist technisch einwandfrei und dem Alter entsprechend in einem gutem Zustand.

Das Gehäuse ist aus Metall und sehr stabil. Die Bedienelemente funktionieren alle.” Link

MAX, Sequential Circuits @ 12 September 2013, Comments Off on Sequential Circuits MAX

“!!!!! Achtung Defekt !!!!!

An alle Bastler
Verkaufe defekten
Sequential Circuits Max Synthesizer + Bedienungsanleitung

Wäre toll, wenn den jemand wieder zum laufen bekommt.
Es ist wirklich eine Rarietät und echt Vintage.Zu schade um ihn wegzuschmeißen.Wär den Sound nicht kennt,braucht sich nur die alten
Depeche Mode sachen anzuhören.
Ich hatte den Syntheziser schon einmal hier auf ebay zum verkauf.
Er wurde auch heil verkauft,aber der käufer hat behauptet das er defekt angekommen ist.Weil ich mich nicht lange mit dem käufer streiten wollte
habe ich den Syntheziser wieder zurückgenommen.
Wahrscheinlich hatte er ein falsches Netzteil angesclossen.” Link

MAX, Sequential Circuits @ 30 May 2013, Comments Off on Sequential Circuits MAX

“Sequential Circuits Max Midi Voice Expander. The cabinet has some scratches. Power supply is included. I am selling this unit for a friend who is a keyboard player. All the keys work and the unit functions as it is suppose to” Link

MAX, Sequential Circuits @ 25 April 2013, Comments Off on Sequential Circuits MAX Project Machine

” Up for auction is a Sequential Circuits Max. It is NOT WORKING, please read carefully. The right end piece is broken, the high C key is missing, the high A and B keys are stuck together and there a few buttons missing as well. All this can be seen in the photos. The inside of the synth appears in tact. The unit powers on but I can’t hear any audio.

I bought this synth as a project but I haven’t gotten around to fixing it up. I’m letting this little piece of music history go so that hopefully someone else can put it to use. Having done some research it seems Wine Country would be the place to send this if you want a professional to repair it. Former SCI employees work there. They also sell the parts at a very reasonable price. The other option would be to use this synth for parts to repair another SCI synth.

If you are reading this you probably know the SCI Max shares the same six voices as its big brother the SCI Sixtrak. It was often used as a voice expander for the Sixtrak. There are editors available online to program this synth. There is a good YouTube video displaying this.

Included is a second hand power supply. I can also include a digital copy of the instruction manual and MIDI implementation manual. ” Link

MAX, Sequential Circuits @ 21 March 2013, Comments Off on Sequential Circuits MAX

” received this item on trade from a local vendor. Was told that it does work, but unable to verify because I do not have the Power Supply for this unit. This item has wear and tear as seen in the pics. It has a broken end piece and missing a key on the right side (as seen in pic #1), missing three buttons on the Multi-Track Recorder Section on the left side as seen in pics 4,6 and 7, (the Track 1 and up and down speed buttons are missing). That appears to be all that is missing from this vintage unit, other than the Power Supply. Unit has a lot of scratches,dents, dings, paint wear/fade, etc as seen in pics. All jacks and Power Switch on the back panel appear to be intact. All 4 rubber feet on bottom still attached. All screws appear to be intact other than the front right side screw where the end piece is broken/missing. Because I am unable to test this item, it is being listed AS-IS for parts or repair.” Link