“I recently bought two Multi-Traks in one auction. I have repaired both units and am selling the newer one. This unit came to me with a power supply problem
which has been fixed.

Here is what I have done to it in the last month or so:

1) Replaced all four damaged rectifier diodes in the power supply.
2) Replaced both large electrolytic caps in the power supply with new parts.
3) Found “battery drain” mod, documented on the web, and applied it.
(Battery off current before mod: 220 uA, after mod ~ 1 uA)
4) Bought new 3V Lithium battery identical to original one, and installed it
5) Designed and built replacement 15VAC power supply using new components (in photo)
6) Found MIDI sysex file of “Factory A” programs (random order) on the web – modified
it to make “Factory B” programs (sounds arranged in groups) and saved it. Unit
contains this currently, but I can download “Factory A” if buyer prefers.
7) Sprayed control cleaner into all potentiometers.
8) Slid “key press stop felt” sideways a little so that keys hit uncompressed places.
9) Cleaned front panel and touched up a few flat black paint areas on rear top edge
10) Copied code EPROM contents into newer EPROM to protect against EPROM “bit rot”
(old EPROM is fine and is included in the auction as a spare)
11) Made real wood (cherry) end panels and installed them.

As far as I know everything is working properly. There are a few small things to mention: The paint on the front panel word “CONTROL” is scratched. There is a small rust spot just to the left of “PROGRAM/PARAMETER”. There are some very small rust spots on top edge of the back panel, and screws that hold the back panel have some rust on them. Also the master tune knob has some scratches on the top. Several of the pushbutton switches might need an extra press every now and then to register, but this may improve with use. For a unit from the 80′s it’s in pretty good shape, I think. ” Link

MultiTrak, Sequential Circuits @ 18 April 2013, Comments Off

“So I took a chance and purchased this a few years ago without a power-supply. On again and off again I would search ebay for power boxes but never came across any… I give up and it’s been sitting for too long.
My loss is your gain. Synth is being sold as-is/untested. This project in good cosmetic condition other than the missing the knobs and plastic sides.” Link

MultiTrak, Sequential Circuits @ 14 March 2013, Comments Off

“This auction is for the Sequential Multi-Trak

Auction includes:

1. Sequential Multi-Trak

Works perfect. Recently professionally serviced and Calibrated by Chris Hewitt at This Old Synth. One of the knobs needs to be adjusted as seen in the photo but the knob is included and this does nothing to the performance of the synth. The knob will be sent safely in a plastic bag.

2. Multi-Trak Manual

3. Multi-Trak Midi Manual

4. Power Supply” Link

MultiTrak, Sequential Circuits @ 28 February 2013, Comments Off

“Rare and awesome MultiTrak synth from ’85. Excellent working order – still sounding creamy. Minor scuffs consistent with age, which I have tried to highlight in the photos. Note this is a US model and this auction includes a compact step-down transformer.

The MultiTrack is six voice polyphonic, with analogue Curtis filters and voltage controlled oscillators, three separate envelopes per voice (amplitude/filter/pitch) and an LFO assignable to various destinations. Controls are via mod matrix for immediate patch editing.

Unusually for an instrument of its time, it is six parts multitimbral, meaning that each voice can play a separate patch and these can be split or layered in any configuration, from a wide unison bass to chord memory techno pads, acoustic emulations, additive synthesis, etc. This is a bit like stackable Oberheims of the day except each voice in the stack can be a different patch and each voice has a separate ¼” output.

“MuliTrak” alludes to the sequencer, which can run each voice independently. It is possible to program a complex rhythm and play a detuned unison lead over it, with each voice going through a different effect, if you wish.

Also features full midi & sysex implementation meaning you can store an infinite number of patches via a software librarian, integrate with your sequencer or DAW (the multitrak’s sequencer gets start/stop signals and track position signals). There exists also some software which lets it run as a VST in your DAW – never tried that but yes, convenient like a softsynth but in fact six voices of the real thing.

Included are the MultiTrak, step down transformer, hard case and download link to the factory patches in .wav format (just play through cassette interface if you wish to overwrite my patches). The synth will be posted fully insured at the buyer’s expense. Collection in person is welcome from London N16. ” Link

MultiTrak, Sequential Circuits @ 07 February 2013, Comments Off

“Sequential Circuits Multi Trak Synthesizer
Model # 615
Serial Number: 01328

I am selling this for parts or repair. It may be a simple fix? Here is what I do know. Battery was dead and has been replaced. Powers up just fine however cannot get regular sounds from synth.
I believe this will need some servicing. I can get some weird spacey sound from Start/Stop track six. This is saved patch 08 and I can get a few faint sound from this with arpeggiation on but nothing else.
Arpeggiation seems to work and rate can be adjusted. Chorus works, can turn it on and adjust settings and hear it work on patch 08.
When I received this there was no power supply. We found one the same voltage, exhaustively had my electronic techs at work pin out 5 pin din and inner power circuit and fabricated a power cord for this. This was done correctly by some of the finest in the business and it fired right up. These guys are pro’s! Unfortunately I couldn’t secure any time for them to dig any deeper into this thing as they are not Synth service men. The din fits in great but won’t stay in unless secured.
I am including the power supply with this synth.
We seemed to be the first ones to open this thing up and internally it was very clean and nothing looked out of place.

Although none or faint sounds come from this, ALL lights, knobs, buttons and characters on LED seem to function properly and work great!” Link

MultiTrak, Sequential Circuits @ 13 December 2012, Comments Off

“You are looking at a super clean, restored analog SCI Multi-trak. Operates perfectly, looks great, sounds amazing, and a rare vintage synthesizer – straight out of the 80′s & made in the U.S.A. It is a sequencer and synth in one, and has the wanted Sequential analog feel and sound.

Great Perks:
-Custom Handcrafted Wooden Sides – Very Smooth
-Brand-new Memory Battery
-Power Supply Built into Synth – Saves space, energy & hassle – Supply includes on/off switch on synth to save power.
-All Keys Work – Depress normally and feel great.
-All Buttons and Knobs Work.
-LCD Protector screen in custom aqua color.
-Sequencer and Synth fully functional!
-Includes Manual!” Link

MultiTrak, Sequential Circuits @ 29 November 2012, Comments Off

“Sequential Circuts Multitrak 615. This units is in mint condition, all the knobs and keys are working and has been in storage for years. It comes with the manual, power supply and neofunk vibes.” Link

MultiTrak, Sequential Circuits @ 16 August 2012, Comments Off

“Another interesting oldie from the estate sale. I have not been able to obtain the original power supply .

I have aquired a 15 vac 2amp power supply and installed an additional jack
in the back to power the unit.

Unit does not turn on. Power supply has three test points 15.5vdc, 6.5vdc and 5dvc and is partially functioning

15.5vdc and 6.5vdc are reading correctly with a voltmeter, the 5vdc line is reading 1.4vdc. This as much as i can tell you

I have not seen one of these on ebay for a long time.” Link

MultiTrak, Sequential Circuits @ 09 August 2012, Comments Off

“I Do not have the power supply and have not tested this ! Sold as is ! No refunds ! Missing one knob !” Link

MultiTrak, Sequential Circuits @ 26 July 2012, Comments Off

“Another interesting oldie from the estate sale. I have been sitting on this for
two months, power supply can not be located.

I have not seen one of these on ebay for a long time.

Sequential Circuits Multitrack Analog Synthesizer

Unit has very cool Prophet 5 style custom wood ends

The faceplace has some white hazing on it.

The keyboard feels good, all key depress fine” Link

MultiTrak, Sequential Circuits @ 19 July 2012, Comments Off

“This is the Sequential Circuits Multitrak synthesizer. It has 6 analog voices, with automatic tuning, and a multitrack sequencer, hence the name. While small in size, this synth packs has some great sounds, even some of the factory patches!

Condition is excellent, both cosmetically and functionally. the end cheeks have been replaced with real wood (oak). Original( black plastic) will be included I case you ever want to switch back to stock.

This synth has been re-capped(electrolytics), and will be shipped with original dedicated power supply, and manual. ” Link

MultiTrak, Sequential Circuits @ 12 July 2012, Comments Off

“Up for the auction is SEQUENTIAL CIRCUITS MULTITRAK (s/n 615 01090) — FANTASTIC VERY RARE VINTAGE SYNTHESIZER * AS IS * NO RESERVE

Dear buyers, the unit is in excellent cosmetic shape, please refer to the photos below.
Unfortunately, I don’t have any information if the unit works – it has a weird power connection (looks like midi port) – so I’m unable to test it at all. Therefore it will be sold AS IS. NO reserve, so grab a bargain.” Link

MultiTrak, Sequential Circuits @ 14 June 2012, Comments Off

“Vintage Sequential Circuits Multi-Trak Analog Synthesizer/Sequencer

· Velocity sensitive, multi-timbral, 61 key

· 6 voice polyphonic

· Multi track sequencer

· A & B Mix and 6 individual outputs

· Velocity sensitive keyboard

· Arpeggiator function

· Serial Number 00069

· Includes power supply, case (foam padded rifle case) and printed copy of operations manual and MIDIGUIDE” Link

MultiTrak, Sequential Circuits @ 26 April 2012, Comments Off

“Sequential Circuits Multi-Trak Classic vintage synthesizer Original power supply included (there is a small break in the insulation near the transformer but it is not exposing any bare wire. You can find additional information about this synth on the web. Cosmetically it is a perfect 10 and will ship to insure that it stays that way. I am selling off alot of my gear because it just isn’t working out for me.” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 02 February 2012, Comments Off


Unit is in excellent condition – no marks on the body, no paint scratches etc…pretty much as new. The plastic side panels have a few scuffs, but also included in the auction is a set of new wooden side panels which are effectively “as new”. The synth still sounds great with a nice loud output & no background noise on the outputs, chorus still sounds sweet.

The only issue i’ve had is that i’ve been unable to get the MIDI output to transmit note data (probably just a bit of dry solder on the connection), but unless you’re going to be using this synth as a MIDI controller then it’s not going to cause you any issues.” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 19 January 2012, Comments Off

“For sale is a vintage Sequential Circuits Multi-trak six voice analog synthesizer. These keyboards are quite rare and very underrated. Similar to a sixtrak, but with more features including an awesome 6 track sequencer arpeggiator. This synth is fully functional and in excellent, near mint condition. Capable of some thick sounds, perfect for pads, bass, leads, effects and more. See pictures below for more details. Don’t miss out on this classic! ” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 24 November 2011, Comments Off

“Sequential Circuits MultiTrak – Analog Synthesizer

selten zu bekommen, unglaublicher Sound!!!, speziell geeignet für experimentelle, komplexe und abgefahrene Klänge, guter Zuszand” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 06 October 2011, Comments Off

“SEQUENTIAL CIRCUITS MULTI-TRACK SYNTHESIZER. Serial number 225. Made circa 1985 in San Jose, California.

This is one of the better late Sequential Circuits synths and has just about everything in a robust (all steel) but small package: 6-voice polyphony, 6 dedicated VCO’s and ADSR envelopes, 99 space patch memory, arpeggiator, real-time sequencer with 1600 note memory, Quantized correction (autocorrect) sequencing, 5-octave velocity sensitive keyboard, split/layer modes, MIDI, lots of modulation routings, stereo chorus with depth/rate knobs, stereo outs and individual voice outs. In all a very powerful and great sounding analog polysynth that was one of the last US-made synths to go head to head against the prosumer Japanese models of the day.

This Multi-Track is in excellent shape cosmetically, in fact it’s extremely clean with the only flaw being a few scratches above the mod and pitch wheels from use. The keybed is very even and the keys all have a good feel. The synth does NOT come with the power adaptor. These can be found sometimes on Ebay or from Wine Country. It was tested with the power adaptor from my TOM and it powers up and works great. Sold as is because of age.” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 07 July 2011, Comments Off

“this auction is for a sequential circuits multitrak synthesizer. The synth is in good physical shape except for the scuffed key you see in the 2nd picture, but the power supply is a bit beat up- the cord was broken in half and re-soldered, and the connections are also taped. it still works, but is not completely reliable, and you will probably want to replace it if you’re going to be gigging with it etc. The synth will ship with its service manual, which was ordered from wine country sequential. there was a period of a few months when the sequencer didn’t work, but then it came back to life for some reason, keep that in mind. ” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 28 April 2011, Comments Off

“Sequential Circuits Multitrak (Model 615) Analog Digital Synthesizer

Includes:

New Battery Installed
World Tour Soft Case
Power Cable (Emu Systems)
Owners manual (photocopy)

Functional condition:

I cannot find any functional issues with this synthesizer.

Cosmetic condition:

I would rate this unit as being in good condition. One of the knobs has a small chip in it but it does not effect usability. In fact, I never noticed it until I started taking pictures for this auction. A more noticeable blemish is the chip in the underside of one of the white keys (replaceable for $10 from winecountry.com) but again it does not impact playability. For a board produced in 1985 this unit is in remarkable condition. Its metal construction has served it well.

The power cord that comes with this unit was manufactured by Emu Systems (you know, the sampler guys) and although it works perfectly, I don’t think this is what originally came with it. I only mention this because if you are a collector, it might matter to you. If you are a musician then it is a non-issue.” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 21 April 2011, Comments Off

“Mint condition synth, in original box. Comes with power adapter.

Quick overview of the synth capabilities: It has 6 voices, which can be used in unison, polyphonically, or split into different sounds. It is possible to write entire songs with nothing but this one unit. It has a built-in sequencer too. There are not many vintage analogue units that boast so much functionality.

As you can see from the photos, this one has hardly been used, and is in pristine condition. Testing of the synth and sequencer functions was all good. ” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 10 February 2011, Comments Off

“I am selling off a few things and this Multi-Trak is going on the block. everything works, a few smudges and scratches but nothing too obvious. Manual and original PSU included” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 16 December 2010, Comments Off

“The following auction is for a Sequential Circuits 615 Multi-Track Synth in excellent condition.. was given to me without power supply.. so I haven’t been able to test it.” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 02 December 2010, Comments Off

“Rare, Vintage Sequential Circuits Multitrak Analog Synthisizer/Sequencer
with power supply, manual and original box!

This Synth is in perfect working order and is in great physical condition, there are a few signs of its age (pictured) but I feel these small blemishes give it character! These synths are known for their battery drain issue in which the battery drains faster than its supposed to, fortunately there is a fix and it has been performed on this unit by a professional technician, however all of the factory sounds were erased in the process. This is not a big deal though because you can reload them via the tape interface or reprogram them using the manual (the manual shows the values for every single parameter for every factory sound!) OR you can do what I do and make your own sounds!!! With the on-board arpeggiator and sequencer you can have hours of fun and make some good tracks too!! I used a custom cable to sync it to my TR606 and MC202 and made some crazy stuff!!! ” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 04 November 2010, Comments Off

“SEQUENTIAL CIRCUITS MULTI TRACK VINTAGE SYNTH.

THIS SYNTH IS IN PRETTY GOOD CONDITION FOR ITS AGE.

THE SYNTH DOES POWER UP BUT IAM UNABLE TO GET SOUNDS OUT OF IT BECAUSE I BELIEVE THE PRESETS HAVE TO BE DUMPED ONTO IT WITH THE TAPE.

INCLUDES THE SYNTH, TAPE, MANUAL AND POWER SUPPLY.

I DON’T HAVE A TAPE PLAYER SO IAM UNABLE TO DUMP THE PRESETS.

ALSO ONE OF THE SIDE PANELS HAS BEEN BROKEN OFF BUT CAN BE FIXED EASY WITH SOME GLUE AND A KNOB HAS BEEN BROKEN OFF AS WELL” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 09 September 2010, Comments Off

“Here we have a mid-80s Sequential Circuits Multi-Trak synth in really good shape. It has been in my basement music area for many years, and is in excellent cosmetic and working condition. It comes with the original power supply. I am selling it as-is because of its age, but as of five minutes ago, it was playing just fine. The keys aren’t even in need of cleaning.

The Multi-Trak was the new and improved successor to the well-known Six-Trak. It is a 6-voice, polyphonic, multitimbral, programmable analog synthesizer with MIDI, a sequencer, an arpeggiator, and a 5-octave, 61-note keyboard that is both splittable and velocity-sensitive. A complete description is here: http://www.synthmuseum.com/sequ/seqmulti01.html.

Sound-wise, the Multi-Trak is the real analog deal. I believe that this one has most or all of the original 99 presets, in order A, although some may have been modified over the years (I have not changed the sounds since I bought this used about ten years ago).

I will include a copy of the original manual in .pdf form. Very important! I also have a nice FAQ I found on the web and copies of the original program settings in .wav and .sys format if you want to restore everything to its original state via a cassette recorder or midi.

Incidentally, this keyboard has a pretty decent organ-like action and isn’t incredibly heavy. It works fine running other midi modules, and although I never moved it around myself, it is certainly portable enough to be used in performance situations.

I wouldn’t be selling this except that I have now switched over to software synths and computer recording. I hate to have good stuff lying around gathering dust. I’d rather it go to someone who will actually use and enjoy it. ” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 26 August 2010, Comments Off

“SEQUENTIAL CIRCUITS MULTI TRACK USED, BUT IN EXCELLENT CONDITION. COMES WITH ORIGINAL POWER SUPPLY, OWNERS MANUAL AND TAPE FOR DUMPING FACTORY SETTINGS ONTO SYNTHESIZER. THE SYNTH POWERS ON BUT NO SOUND PLAYS WHEN KEYS ARE HIT. EVERY BUTTON LIGHTS UP AND WORKS AS IT SHOULD. I THINK THE TAPE NEEDS TO BE DUMPED TO THE SYNTH BUT I HAVE NO WAY IN DOING THIS BECAUSE I DO NOT OWN A TAPE PLAYER. SO IAM SELLING THIS SYNTHESIZER AS IS. THIS IS A VINTAGE PEICE OF GEAR AND IT HAS BEEN WELL KEPT AND LOOKS GREAT FOR ITS AGE.” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 08 July 2010, Comments Off

“Very nice 80s-vintage synthesizer. Lots of data available for it on sites like www.sonicstate.com. It has six voices and one VCO, filters, arpeggiator and sequencer. This unit is in near-perfect shape. No broken or missing parts. Unlike most synths I’ve used, the pitchwheel on this unit isn’t spring-loaded. It has a detent that indicates it is centered. Classic sounds and easy operation make this unit lots of fun. Comes with an Anvil road case in decent shape.” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 24 June 2010, Comments Off

“Rare vintage Sequential Circuits Multi-Trak 6-voice polyphonic analog synth with full MIDI support!

Item is in mint condition, fully working, clean.
A very underrated analog synth from the 80′s. Has built-in sequencer and
arpeggiator. Just serviced (removed factory PSU noise, now has new backup battery and voice chip,
battery drain fix modification applied). Voice architecture is based on 6 Curtis CEM3394 chips – Sounds great!

Operation manual, service manual with schematics, original PSU (110V), 110-220V adapter and backup tape are included.” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 17 June 2010, Comments Off

“Everything works on this vintage beauty. Please notice a small space between two keys. One key is slightly bent to one side, this key makes a click when you hit it, but in no way affects the functioning of the key or the amplified sound.” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 29 April 2010, Comments Off

“I am selling a Sequential Circuits Multitrak. I have replaced the battery and also did the battery drain fix modification so that the new battery will last 7 years instead of 3 months, you can see the picture of the battery mod i did. It is a common problem on most multitrak’s the battery drains in less than 3 months. The link for the battery mod is http://www.k5000.org/gear/MultiTrak_battery.html. I also got a brand new custom made power supply built for the multitrak. These power supplies are not made anymore, they are rare and hard to find and to get a brand new one made would cost at least $200. I had mine built from a professional technician. The physical condition is pretty much perfect, with no major scratches or marks on it as you can see from the pictures. Everything functions as it should. There are no presets on it, but the battery does work so you could load all the presets if you wanted to.” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 01 April 2010, Comments Off

“Sequential Circuits Drumtraks 1980s vintage drum machine. Comes with 2 additional EPROM chips pre-loaded with samples–one is labeled “Toms” and the other is labeled “Lo Conga”. You can also load the chips with your own samples. Also includes owners manual and an SCI chip demo data cassette.

I have used this machine on and off for about 6 years but no longer have room for it. It has been tested and is 100% working. I haven’t tried the other 2 chips but they look brand new and I have no reason to believe that they don’t work.

Condition: This machine is very solid, cosmetically it is in very good condition and it is extremely clean. There are some dings and scuffs on the wood, one small scuff and some scratches on the metal face (upper right–see pic). The tuning knob is slightly bent but this does not effect its functionality. The metronome volume knob is also slightly bent and missing the cap portion (see pic) but still works perfectly. ” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 01 April 2010, Comments Off

“This is a Sequential Circuits Multitrak. I found it in a pawn shop and brought it home. They had no power supply, so I bought a brand new one from Wine Country who seem to be the SC experts. I’m not in need of the keyboard as I mainly use VIs for better or worse. I plugged it in and everything seems to work fine. The presets are in memory, so the battery is functioning. I was able to move around the various functions of the keyboard and tweak to my hearts content. The synth sounds very good. The only thing that I could find not working is the down range of the pitch bend. Pitch will bend up, but not down. The pitch bend wheel moves down fine, so I’m not sure what the issue might be. Other than that, I haven’t found anything that’s not working. The synth is guaranteed not DOA, but it is 25 years old or so and sold as such. ” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 18 March 2010, Comments Off

“The synth is in good working condition except three keys that sometimes get stuck. They should be exchanged as well as the battery (3V Lithium) which is empty.
It comes with manual and orignial american power plug. You can have the converter (see picture) for european plugs if you want, it is a bit heavy though and will maybe raise the shipping costs.” Auction ended. Click here to browse on eBay.

MultiTrak, Sequential Circuits @ 11 March 2010, Comments Off

“Ich verkaufe hier meinen gebrauchten und echt nostalgisch verrückten Synthi, den Multitrak von Sequential.

Das Teil ist sehr speziell und hat einen echt eigenwilligen Sound, der aber echt fett ist.

Gebaut wurde das Teil in San Jose Californien, ich glaube 1978.

Ist mit eines der 1. Geräte mit Midi Ansteuerung.

Der Synth ist gebraucht und gepflegt.

Über die Funktionsfähigkeit muss ich etwas vorsichtig sein.

Es gibt Tage, da schnurrt das Teil wie eine Katze und alles funktioniert.

Dann gibt es wieder Tage, da gehen nur manche Töne und Tasten.

Keine Ahnung was dem Synthi fehlt, wahrscheinlich ist es die Californische Sonne. J

Habe ihn das letzte mal vor 10 Jahren am Cubase SX via Midi / PC laufen gehabt, da spielte er alle Töne usw.” Auction ended. Click here to browse on eBay.