Keyboard Synthesizers

On this page you will find all the information I have collected and used for my own interest, repairs and modifications on the keyboards, synthesizers, & sound boards found in my studio setting. Some of the information is general and some of it rare. I hope you find this page helpful in understanding these musical instruments.

General Maintenance & Repair Tips

When cleaning any electrical component, try using a can of compressed air before spraying or applying chemicals. Even if you plan on using chemicals it's still a good idea to start with a can of air. Air it out before you wash it out. Words to live by.

Consult people who repair recording consoles & the like. These technicians have the experience & are usually up to date on great, currently available, cleaning & lubricating chemicals.

Take your time. Maintaining, modifying or repairing your musical equipment should never be a rush job. Drop me an email or get advice from groups, forums or blogs found on-line.

Always be on the lookout for good cleaning chemicals. Use the net to save yourself time & money searching for a desired cleaning or lubrication solution.

Cleaning Buttons, Faders, Pots, Sliders

My opinion of DeoxIT FaderLube...
Because of the residue it creates, I find I use it as a last option.

DeoxIT FaderLube F5 (5%) part#F5S-H6 is a common product used to clean volume, tuning, joystick and arpeggiator pots. First take the plastic knobs off your component, then remove the individual PCB boards from the synthesizer or component's body panel. In some cases you will have to fully unscrew individual PCB boards that the pots are connected to. Once the PCB board has been removed, spray the DeoxIT onto the desired pot. Spray at a downward angle, trying not to get any of the spray residue on the actual circuit board. DeoxIT dries gummy, and over time will show up green & gummy. DeoxIT sprays pretty heavy. After applying DeoxIT, turn the pot knob back and forth while wet with DeoxIT so that you get the solution down into the pot fixture. This should get any dust or sticky stuff that has collected around the fixture. Stiff movement aorund the pot knob as well as any audibal scratching noise should be gone after application. I spray each knob twice and after each spray I move the knob back and forth many times. DeoxIT can be found for about $12-15 a can at a number of on-line retailers. Try not to be messy, as the more you apply the more you will have to remove.

While DeoxIT is the most abundant and available, my current cleaner lube of choice is...

Miller-Stephenson MS-738 "Contact Re-Nu & Lube".

This product, while a little expensive, is fantastic in application, with an end result that leaves 0 residue. Application of the product is for the most part the same as the DeoxIT. But the end result is a well lubricated invisible residue finish. Having used both, DeoxIT & MS-738, I feel it's safe to say that the MS-738 is probably the best on the market. Email me & let me know what chemicals have given you good sucess, amd let me know how you have used it & what you used it on. I am always open for good chemical advise.

To find MS-788...
* contact the Connecticut office location *
Danbury, CT 06810

Battery & transformer Matching!

When replacing a battery or a transformer, match the battery or transformer with the one that is broken. Just because it's the same size as the other or looks just like the other or fits into the housing like the other, doesn't mean it's the same. Sorry this is just a common mistake that has showed up more than once when I have been asked to repair a component or synth.

Wrong batteries & transformers can damage components.
Please be advised.

KickRaTT logo
KickRaTT Productions

KickRaTT, I performed & released music under this title between 1989 to 2002. I also used the name for a mobile digital recording service that I offered to DJs for House Parties & Clubs. My field recording service also went under the title of DATMAN. At live performances I still use the KickRaTT name in reference to my hardware rig. For the most part, the KickRaTT name is more historical to me now, yet The logo above has been used on countless tapes, CDs & t-shirts for self-promotional efforts, in Florida, California & the Pacific Northwest. Fond memories & forgotten efforts.

To get rid of Cleaning Lube Residue

On pots and switches that get stiff and gunky, I usually use Isopropyl alcohol to clean the parts first, then lube with a sparing amount of contact cleaner. Using the Miller-Stephenson MS-238,
is a waste of good cleaner/lube. The alcohol works just as a solvent, after it's all clean, then use the contact cleaner. If I don't have the 99 % type, I use the drug store stuff. They usually have 2 kinds, one is 70% alcohol & 30 % water, the prefered version is 91% alcohol & 9% water. Also a product, Electrolube DFL spray works great on many mechanical parts that you want to stay clean and dry. Adds a Teflon dry coating with no oils. If you use a syringe to apply the alcohol, you can get it into pots and semi-sealed switches easily.
For really stubburn gunk, I use denatured alcohol. It's stronger, and available by the quart in the paint section of any hardware store. However, be careful around polystyrene plastics with any cleaner. Polystyrene plastics melt really easily.

To get rid of FLUX Residue

If you have had to modify or had to repair the components found within your musical gear, you have probably had to use your soldering iron. For repairs and mods to a commercial PCB, I always use a CLEAN standard solder, which means my type of solder is going to create a FLUX residue that I will need to CLEAN up after the solder has cooled. The tecnique I have used to remove the FLUX after a repair or mod to an already populated PCB, is to use a small brush with denatured alcohol. First scrub the flux loose, then place a folded paper towel over the wet area and scrub or dab lightly from the top side to absorb the wet flux into the towel. This keeps the flux residue from spreading all over the pcb.

Akai s5000 sampler
Akai Professional 1999

A Great Software Utility for converting AKAI samples
Translator 6

akai s5000

Dave Smith Instruments

What sets this synth module apart is the sub oscillators!!!
e-mu products
before and after 1998

I have owned and service a number of these modules over the years. I understand the appeal. The manufacturing of these sound modules drasticly changes in 1998. Production of these sound modules went to China in 1998 and stayed in China up to when Creative purchased E-mu corporation. All of the sound modules made prior to 1998 were made in the USA. Currently Creative has all E-mu products as listed OUT OF SERVICE, and no longer even supports information, documents, downloads or operating system updates for any E-mu product produced prior to 2008. There seem to be a number of opsys FATAL situations that render the E-mu products produced after 1998, useless. So not only is there little to no support for these products, they are prone to fatal error death.

e-mu procussion module
Date Produced 1993


emu procussion

e-mu ultra proteus

Date Produced 1994

emu ultra proteus
e-mu XL-7 command station
Date Produced 2001

Service notes...
on boot I got this message...
"Error! Code = 001 Fatal: Bad Instruction"

After re-installation of operating system v1.31 I got this message...
"Error! Code = 001 Fatal: Ftrap error"

Attempts to diagnose the station without a ROM chip yeilded this message...
"Error! Code = 000 Missing Tag!"

You also get this last error message if you attempt to install without ROM chip.

I used a Windows XP serv. 3 with the E-loader application to re-install various versions of the XL7 command station operating systems , in my attempts to resolve these FATAL ERROR messages (see above service notes).

Contact me if you are having a hard time finding any of these legacy E-mu softwares; E-loader or OS uploader. I do have all the opsys files versions 1.1, 1.31 & 2.0 all supporting documents for XL7 command station. 

I was unable to get E-loader to work correctly under Windows 7.
E-loader does require Java runtime. I do suggest finding a Windows XP workstation or laptop.

while using the E-loader application on Windows XP

I have found that with everything connected properly the application will display the message that there is NO DEVICE AVAILABLE TO RECEIVE or that NO RECEIVE REQUEST AVAILABLE???

I have fixed this by reselecting my TARGET MIDI DEVICE.

By doing such, the application reestablishes communication with the XL7 command station.

After restablishing communications the OS upload proceeds accordingly.

After Installation

A difference between the two operating systems or as a result of hardware failure, after the downgrade operating system re-installation, v2.0 -> v1.31, I observed that the ON/OFF button on my XL7, turned the unit OFF immediately once depressed. In my previous XL7 v2.0, pressing this button initiated a 5 second countdown.

My attempts to fix this FATAL ERROR on the XL7 were unsuccessfull. These were attempt to reinstall Command Station .dli file for versions 1.1 & 1.31. After both re-installations the same FATAL ERROR messages were displayed  with or without ROM card chip installed.

I also moved the ROM chip from slot(0) to slot (3) to see if this had any effect on the various FATAL ERROR messages I received.

Re-installing the various operating systems for the XL7 did not solve the problem.


emu command station FAQ

emu xl7

e-mu X-board midi controller

Date Produced 2006


61 full-size keys with aftertouch
4 Zones per patch
Latch Mode for triggering drum loops
Snap Shot mode
16 realtime controllers
16 patch select/program change buttons

For anyone maintaining a Windows XP or 7 DAW as part of their studio, & who has a need for the Emu sample collection, & who wants the synthesis engine of the Emu command stations, I would seriously consider these two products; EmulatorX3 & ProteusVX. These two products in conjunction with my Xboard make for one awesome sampler / rompler setup, with strong hands on synthesis abilities.



I have also found most, if not all of the emu sound module samples available on the web.


Proteus VX
Creative support
X-board manual

xbrd61 emu

Guitar Pedals

I use a 
bank of guitar pedals for both effect processing and synthesis. I have a dedicated page on this subject.

Boss pedals by Roland
Electro Harmonix

Modulations & Ensembles "current development"

Korg Poly61
Keio Laboratories Polyphonic Synthesizer produced in 1983

6 Voices Polyphonic Synthesizer with 64 patch memory
DCO1:sawtooth, pulse, and square; DCO-2: sawtooth, square
1 LFO can modulate the DCOs or the 1 lowpass filter w/ ADSR
1 VCA & 1 ADSR

History of the Synth

This synthesizer was designed and built by the Keio Laboratories of Tokyo, Japan 1983-84, it replaced the Poly6. The Poly6 was one of the last machines built prior to the third revelation in modern synthesizer design: the digital synthesizer. (The first was Bob Moog's use of voltage-controlled elements; the second was the incorporation of microcomputers into the hardware to allow for programming, editing, and storage of patches). The poly61 represents a stage of design between the poly6 and the poly61m (midi). The poly61 a digitally controlled version of the poly6, it is the last in the line of Korg synthesizers prior to the introduction of midi.

This Poly61's issues...

NOTES: Current issues and obvious problems

1. Need to check battery and identify version.

2. Sounds weak at first power up, sounds ok after it warmed up.
approx. 30 min to warm up. All six voices appear to work fine. The Bando PSU will probably need to be replaced.

Buttons took some tapping or don't respond well to first pressing. A delayed or jumping of the value displayed from a desired parameter could be observed.

The two Poly61 versions

The Poly61 was produced in two versions, an old and a new production version. This Poly61 that I am working on is the newer production model.

The first identifier between the two versions is the internal battery; v.1 had a soldered drum battery right on the PCB, it is recommended that if you have identified this on your Poly61 version that you remove it, as these batteries tend to explode with age. Version 2 has a battery that is seated on the synthesizers PCB that is just like a cr3032 found on almost all computer pc motherboards, it's about the size and dimensions of a quarter and is easily removed with a small screw driver or pick(more on this below).

Second difference in the versions, in the older models you will find the Poly61 v.1 had a number of extra boards installed; Antilog amplifier board & a CPU Correction-board, that fixed a known cpu bug issue.

A piece of histroy in my opinion, as I stated earlier, this Korg model is one of the few manufactured synthesizers that bridged the gap between the old analog keyboards of the 70's to the digital synths of the 80's. I have a real love for the sounds of the synths of the early 80's, I grew up with them & their sound has become quite nostalgic.

This is a Poly61 v.2

The following boards are present in my Poly61 v.2

A) Controller / Clock-board which handles the volume, tune & the joystick functionality, also controls the primary oscillator. # KLM-477B

B) Programmer-board, for selecting presets and the editing of each patch.  #KLM-481A1

C) Assignment-board which controlls voice assignment and the arpeggiator.

D) Connector-board for signal output, headphones & cassette interface. #KLM-478A

E) CPU-board #KLM-509A

F) The 6Voice-board & analog tone generation #KLM-508A

G) Power supply is a +5V/+-15V BANDO TA-009

BANDO power supply company 

Battery Replacement

The Battery type in my Poly61 is a Panasonic BR2325 3volt, looks alot like the standard CR3032s found on PC motherboards and components. Panasonic BR2325

The older issue Poly61 had the battery type directly solderd onto cpu board KLM -475B - THE BATTERY IS A BLUE ONE from VARTA and has the following written on it

3/170 DK
14 Std. Laden
mit 17mA

The older production POLY61 battery looks like a small blue barrel. I have read a number of related articles about this battery type leaking or even exploding outward onto the motherboard. : (

Remove the battery if you have one of these. It should play fine even without the battery, the battery is there only for preset reservation. So the synth should work you just won't be able to save any preset changes. If you have to replace this battery on your version of the Poly61, remember it is very important to identify and match the battery type. The actual work involved once you have the battery type is easy and shouldn't be much of a problem if you know how to properly solder.

Push Button Replacement

The replacement switch types for this version of Korg Poly-61 are:
Momentary Push Switches (11mm sides). These are the square push buttons that you will find underneath the large plastic push buttons found  in the VALUE, PROGRAMMER, KEY ASSIGN & ARPPEGIATOR sections on the synthesizer above the actual keyboard. These push buttons will have to be solder removed and then the replacements will have to be re-solderd back in.

These momentary push button parts were also found at
Vintage Planet for about $20.00 a full set.

Oaktree Repairs

Momentary Pushbuttons on KLM boards
Vintage Planet
KG-37505000    Tact Switch KHC10901 . . . . . . . . . 0.75
KG-37505000S   Full set of 22 Tact Switches . . . . . 15.45
KG-37503400    Program/Function Push Switch . . . . 0.75 *
KG-37503400S   Full 19-Switch Replacement-set . .13.25 *
* PART = KHC-10901 from the Korg Poly 61 service manual

korg poly61

poly 61 02

poly 61 03

poly 61 04

poly 61 05

wavestation banner
Korg Wavestation
 & wavestation SR module (not pictured)
Date Produced 1990-1994

32 voice Polyphonic Digital Synthesizer
Digital synth w/ 2MB ROM samples
Vector Synthesis & Wave Sequencing
Multitimbral - 16 parts
1 LowPass filter per voice
150 patches in stored memory
onboard effects

History of the Synth

When Sequential Circuits finally went belly-up, their research and development into vector synthesis was picked up at Korg. This led to the hugely successful Wavestation Synthesizer which was based on Sequential's ProphetVS. The Wavestation incorporated the 2-dimensional vector joystick of the ProphetVS which allowed the user to alter and animate sounds.

The Korg Wavestation was a vector synthesis synthesizer produced in the early 1990s. The Wavestation's "Advanced Vector Synthesis" sound architecture resembled early vector synths such as the Sequential Circuits Prophet VS. Designed as a "pure" synthesizer rather than a music workstation, & unlike any synthesizer prior to its release, was capable of generating complex, lush timbres and rhythmic sequences.

Korg added to this a second break-through form of synthesis: wave sequencing, by which short segments of sampled audio waveforms could be played one after the other and cross-faded into each other for some complex and unusual tones, pads, textures and rhythms. The Wavestation had 2MB of ROM based samples at your disposal. Programming is not exactly easy but this great digital synth is capable of lush ambient sounds and strange effects. It has the obligatory lowpass filter, though it is non-resonant and digital sounding. Also on-board are some multi-effects which are pretty nice. This synth is easily upgraded and expandable with PCM cards too.

The two primary synthesis concepts designed into the Wavestation were Wave Sequencing and vector synthesis, the latter Korg dubbed "Advanced Vector Synthesis." Although the Korg Wavestation was the first keyboard that used Wave Sequencing, its roots can be traced back to earlier wavetable synthesizers, such as the PPG Wave of the early 80s and the Prophet VS by Sequential Circuits, Inc., 1986. Wave Sequencing improved on Prophet VS by incorporating the ability to crossfade up to 255 waveforms, rather than only four. Another advancement was that a wave sequence could be programmed to "jump" to any PCM wave in ROM memory, whereas similar synths were designed to move sequentially through the wavetables.  The combination of vector sequencing and wave sequencing really put the Wavestation into a league of it's own.

In 1991 the Wavestation EX, also called EXK-WS, was released (pictured above). The EX added 150 more waveforms (4MB) including acoustic instruments and drums. The EX also adds 8 multi-effects including: Mod Pitch Shift-Delay, Stereo Compressor-Limiter/Gate, Vocoder, Overdrive and Distortion effects, transposable keyboard and added MIDI implementation and control.

Here are the expanded effects of the KORG wavestation

Wavestation expanded effects

Korg Factory Sounds

Here are the system files that you will need to get your KORG Wavestation back to it's initial configuration. 

KORG factory presets

Wavestation A/D RAM3 Bank:

Wavestation EX ROM Card Bank:

All sounds in these banks are copyright Korg Inc.
This site is not affiliated with Korg in any manner.

Wavestation links

wavestation LCD upgrade
wavestation backlight

korg wavestation ex

Novation Supernova

Date Produced 1998-2000

Novation Supernova

Roland JV-1010

w/ vintage keys expansion ROM
Roland Corporation 1999

roland jv1010

Roland JX-8P

Roland Corporation 1985


Polyphony: 6 voices with  64 patches
Oscillators: 2 DCO's per voice (12 oscillators),
VCF/ VCA: low-pass and hi-pass filter
2 ADSR envelope generators per voice
keyboard with velocity and aftertouch
portamento & chorus effects

History of the Synth

The Roland JX-8P was a 6 voice polyphonic synthesizer released by Roland in 1984 to compete against the Yamaha DX7. Programming was achieved either by means of a data slider and a silkscreened data table designating each of the parameters, or by means of a separate unit, the PG-800 programmer. It was possible to create monophonic sounds, using a set of oscillators (2 from a patch) or 6 at the same time (with the same patch) to create a 'denseness' effect in the patch. The built-in chorus effect was switchable from off to two different modulation modes for every patch. Memory organization consisted in two internal blocks of 32 'patches', and a similar organization for the external cartridge. Patch memory could be dumped to MIDI with a SYSEX message, with no "handshake" necessary. Initially, the owner's manual offered a programming sheet where parameters could be written on the blank lines. SYSEX memory dumps could be sent or recognized as "one patch" and "one bank". At the moment of receiving a memory dump, the synthesizer would keep all received patches in a memory buffer. In order to write the buffer to memory, the memory write lock had to be switched to "write" mode. The memory write lock was a physical switch in the back of the instrument and could be changed on the fly without the need of turning the instrument off for fear of damaging the memory (which was common on similar synthesizers).


JX Aftertouch repair
PG800 reference

Roland JX-8P

Roland RS-09 (Organ/Strings)
Roland Corporation 1980


roland rs09

Sequential Circuits Pro-One

Monophonic Synthesizer produced between 1981-1984


Oscillators - 2 VCOs: VCO A saw/pulse, VCO B saw/tri/pulse, Noise
LFO - saw, tri, pulse
Filter - CEM-3320 Filter chips: 4-pole lowpass with Cutoff, Resonance, ADSR Envelope, Keyboard Tracking
Keyboard - 36 keys
Arpeg/Seq - Arepg: UP, UP/DOWN patterns
SEQUENCER: 2 patterns of pitch info only, 40 note capacity.
Extrernal Control - CV/GATE

History of the Synth

Sequential Circuits Inc., was a California-based synthesizer company that was founded in the early 1970s by Dave Smith and sold to Yamaha Corporation in 1987. The company, throughout its lifespan, pioneered many groundbreaking technologies and design principles that are still practiced today. The ProOne was introduced in 1981, and sold for under $1,000. The pro-one was promoted as the little brother to the Prophet 5. What is unique to the ProOne is that the oscillator frequency, pulse width and the filter cut-off can be modulated, either directly or by using the wheel, the filter envelope, the LFO or it's second Oscillator.

The pro-one as I found it...

This ProOne arrived to me, DOA. The unit had obviously been sitting around for many years. The previous owner had no use or time to spend on repairing the unit. This ProOne for the most part was dead. The drone light would light up, and you could get noise from the audio out, but that was about it. After opening the ProOne up, taking a good look at the circuit board, nothing looked burnt or blown. What is nice is that ProOne under the hood is just one big PCB. I found all of the wiring cables, keyboard & power supply dust filled. This was going to be worth the fix even if I can't get the keyboard to work, if I could get the CV INS to work this circuit board, I maybe could make this synth into a rack version. So I acquired this synth for $85, felt sure of myself that I was going to fix it and in doing so supported my love for vintage hardware and hopefully get out of it a valuable piece of gear for my music rig.

Here are the things I did, where I found the parts I had to get, and my procedures for overhauling this Sequential Circuits ProOne. I am determined to get this fully functioning for a low cost!

Identifying your ProOne is essential before getting into repairs. The keyboards on the ProOne were either j-wire types or membranes types. My ProOne is a j-wire type keyboard. If you are reading this and have identified your ProOne as a membrane type, I have a bit of bad news. It seems repairs to the troublesome membrane switch contacts were only temporary at best due to the inherent unreliability of the switch design. You might try detaching your keyboard and DIY design your ProOne into a rack mount version to be controlled either by CV or installing the synhouse midi controller card for operation. An idea I am even considering just due to the age of the keyboard and the lack of play it has. Even on the J-wire types, the cost of totally overhauling and cleaning the keyboard part of the synth, can be a bit pricey. I have connected the control voltage & gate inputs of the ProOne to my Q104 midi interface to test out the ProOne's operation through control voltage control and it works perfect. This way I still can make use of the ProOne without having to install the synhouse midi jack.

Power Supply Replacement

The internal transformer power supply of my ProOne is very old and looks a bit corroded, so in addition to working on the keyboard I want to replace the transformer with a newer one. Now finding a power supply to accomidate this older synth will seem tough on first try. Most of the on-line sequential circuits repair websites, will either not have any available transformers or will replace the power supply only if you buy into much larger repair/modification services, making a simple job very expensive. Not that some of the upgrades or modifications that they offer aren't great additions to you ProOne, it's just that you may find that suddenly just getting power to you vintage ProOne has become a huge expense. It did take some time for me to identify a modern day compatible transformer that is the correct replacement to the original.

The power transformer needed for the ProOne replacement is a type (Signal Transformer DP 241-5-36) the D stands for a dual operation of 115/230v, see the spec sheet for this transformer. You can find these available at Digi-key but I recommend calling Signal Transformer direct (516)239-5777, to get the DP 241-5-36. Direct from Signal Transformer, the transformer can be bought for about $14.00 each. Buy 2, 115/230v transformers if you can. For all of my synths when buying repair parts I almost always buy 2. I like being able to repair things on the fly rather than having to wait for the part to come in the mail. You will always have good extra if you plan on holding on to your ProOne forever. Here is the link to the manufacturer Signal Transformer Corp product# "DP 241-5-36"

Fuse for Pro One

A 1/4 amp Slo-Blo fuse is required for use with 110 VAC, and an 1/8 amp Slo-Blo fuse is required for use with 220VAC. This is the factory fuse spec for the ProOne. I have found that RadioShack fuse#270-1002 1/4 amp Fast Acting Fuses work fine with the new Signal Transformer Dp 241-5-36.

Cleaning the Pot & switch controls

If you can't get a hold of the Miller-Stephenson product. Use a small amount of Deoxit Faderlube(5%), work the pot's shaft gently back-and-forth a number of times. Use the 5% stuff so you don't gum up the switches and pots with residue. Here is the stuff I use, which you can order on-line.

Deoxit Faderlube


Wheelbox modulation replacement

The last thing needed to really get this ProOne back to a level of functionality will be the wheelbox, for pitch & modulations. My current options are, a repair the original. Build my this
a backlite wheel mod for a moog synth
a DIY mod wheel replacement
or buy the ProOne kit from synthwood. DaveSmith instruments (707) 963-7006 make a custom wheelbox, it is the one in the kit from synthwood,  I really don't really care if it's backlit or not, I just want a functioning durable wheelbox.

Rather than buy an entire wheelbox kit, I decided on finding replacement parts for fixing the broken one. Parts for this synth as well as many others can be found at Vintage Planet Buy the replacement parts that they had in stock cost about $30. And the wheelbox was restored to full functioning. Part numbers change at Vintage Planet as the part become available or are sold. So I don't have a reference number to give. But finding parts is pretty easy on their one rather large page listing of parts for many vintage keyboard & synthesizers.


Vintage Planet
wine country
Pro One membrane keyboard repair
Pro One modification

sq pro one

transformer image

Sequential Circuits Prophet 600

Polyphonic Synthesizer produced in 1982

The Prophet 600 is the first synthesizer to have midi functionality.

prophet 600

Soundtracs Topaz

In-line 32-8-2 Recording Console produce 1994

Topaz Information Introductions
Topaz Electronics
Topaz PSU Transformer Project
Topaz meterbridge VU bulb repair
st topaz 32

Waldorf microQ

Date Produced 2000-2001

waldorf microQ

Studio Equipment

Date Produced 1985 - 2010

I have many other pieces of equipment in my studio that help to make my sound and aid in my home recordings.

equipment logos

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Saint Augustine, Florida