Made a analog style sequencer using an Apple II.

It’s equipped with a Mountain Computer ADC / DAC board.

The board can read in 16 channels of voltages.

It can also output 16 channels  of voltages.

Voltage ranges are -5 volts to +5 volts. 

Resolution is 8 bit whether reading or writing.

Using a blank piece of aluminum panel here, 16 NOS Moog 100K linear pots and some new Cosmo (Moog) knobs, I built a crude 16 stage sequencer within 2 hours.

I also included 16 capacitors that cured a small problem with channel to channel interactivity.

I then programmed a traveling bar graph displaying notes as vertical bars of varying height.

The top of each bar would flash as that particular note played.

All software is written in Applesoft BASIC. 

The code was very short.

Making a change such as the choice between V-trig and S-trig outs was one line of code.

Using one of the game paddle inputs, I added a pot for use as tempo.

I also added a gate output jack, along with both a positive CV out channel as well as an inverted CV output jack. 

Again, inversion was as easy as adding one line of code.

The sequencer can be run forwards or backwards.

It could be a single channel 16 stage analog sequencer.

Or an 8 stage with variable duration per stage via the second row of 8 pots.

The Apple’s stock cassette jacks could also be programmed to allow syncing the sequencer either to or from an external source, change the direction of the sequence, etc.

In hardware, I plan on adding some opamps to offset the CV out(s) to 0 – 10v instead of -5 to +5 and additional drive capability.

I may also add a gate LED and driver. 

In software, I plan on adding variable stage length, duration (as an 8 stage) and a quantizer.

Also a preference page allowing choice of colors for the display and other settings.

A method of changing direction on the fly would be desirable also.

One problem: The bar graph display does not update the note heights until the next cycle of the sequencer. Therefore, changing stages while playing does not show the changes graphically without a considerable delay.

This is me testing out a quickly built 16 stage sequencer using an Apple //e computer.

It only took about 3 hrs to build the panel and write the (pretty crude) software.

LOTS of possibilities to explore in the future though.

The Apple has a Mountain Computer 16 chan ADC / 16 chan DAC.

Everything written in Applesoft BASIC.

The synth is a Moog 55A that’s here for service. 

Nothing serious going on here.

Building the sequencer and taking the video were just for fun. 

Short story:

Long story:

I (very quickly) hacked together an analog style sequencer using an Apple II computer equipped with an old Mountain Computer ADC / DAC board.

This board can read in or output 16 channels of analog voltages.

Voltage ranges are -5 volts to +5 volts (though I can change this.)

Resolution is 8 bit, but it’s still fairly accurate hitting note CVs closely.

I made the panel from a piece of scrap aluminum I found here

Used 16 100K linear pots (NOS Moog) and some new Cosmo (Moog style) knobs.

Built and wired it up along with some vinyl lettering in around 2 hrs. 

For software, I programmed a traveling bar graph that displays notes as vertical bars of varying height.

The top of each bar would flash as that particular note plays.

One CV out jack is the “normal” mono out. 

A 2nd CV out jack is right now programmed as being the same notes, but inverted.

The gate out jack can be whatever- V-trig, S-trig, pulse. 

In the video it’s making S-trigs for the Moog 911 envelope generator.

Software is written in Applesoft BASIC. 

(Comes built-in on the Apple.)

The code was incredibly short. I couldn’t believe how little it takes to write something like this.

Making any change such as adding a quantizer, variable note durations or sequence length takes about 1 or 2 lines of code.

Right now it’s programmed as a single channel 16 stage analog sequencer with mono CV out.

But I might make it be an 8 stage with the second row of 8 pots changing the duration of the first 8 stages.

A 30+ year old computer driving a 30+ year old synth can still be a lot of fun.

This critter could also be programmed to allow syncing it to or from an external source.

You could even make it go backwards or write a “performance” to disk without too much work.

File date: 12/21/2010

File date: 11/26/2004

Why the white Arp Odyssey is not always “the better Odyssey”

1. White Odys have more trimmer adjustments and are more difficult to calibrate.

2. White Odys used a three buss keyboard using silver plated spring contacts.
Later units used a two buss action with gold plated J-wires.
Therefore, black Odys have less contacts necessary, better conductivity, less or no tarnish, self-wiping contacts and are easier to adjust and repair.

3. It’s painted thinly. The board standoffs cause front panel paint cracking.
Black Odys are painted more thickly.

4. White Odys are older and thus their sliders and switches are more worn and have had more time to accumulate dust.
Capacitors, resistors, trimmers, rubber keyboard standoffs and bushings are older too.
Older synths on average have also seen more service, more wear and vibration.

5. It’s white. This was changed to black later because it was too annoying on brightly lit stages.

6. White Odys have their power switch mounted to a PCB.
Removal of that PCB is more difficult than in a black Ody.

7. White Odys have fewer interface jacks.

8. White Odys actually sound *less* Moogy than black ones because their filters are -12db, instead of -24db like Moogs.
It should also be noted that Moog never sued Arp over the filter design.

9. White Odys have a transistor noise source, while later black Odys used a zener diode.
Zeners make a more consistent noise with less spikes that can damage speakers.

10. White Odys have slide switches which have a bracket in front of the contacts, making them harder to clean than black Odys.

11. The keyboard connector on Black Odys is one piece.
White Odys have the same connector, plus an extra wire attached to the extra buss of their three buss keyboard.

12. Later black Odys have a removable power cord and a hinged front panel making service easier. Instead of 14 screws to remove, there’s 4.

13. Later black Odys have PPC and can thus inject the LFO equally into both oscillators simultaneously while playing. Impossible on a white Ody.

14. White Odys use two additional digital CMOS chips in their oscillators, making them more unreliable and less analog than black ones.

15. White Odys used smaller rubber feet, which can shear off more easily than black Odys.

16. White Ody panels used no welds. Black Odys welded their keyboard mount pieces and corner seams.

All in all, black Odysseys are more reliable, more stable and cheaper to buy and maintain.
It’s only logical that Arp strived to *improve* the design over the years.

Original File Date: 1/24/1996
Original file appears below, with all typos intact.

Kevin Lightner is one of a rare breed. He has put together what must well be
some of the largest modular systems on the planet. Systems we mere mortals
could only dream of owning (or perhaps even just touching) have passed
through his hands. If the names Serge (66kjpeg), Aries (66kjpeg), or maybe
more familiar names like Moog (50kjpeg) and Emu make your heart race prepare
to meet the man who puts these monster modulars together, as Recoil coaxes a
short interview and photos out of Mr. Kevin Lightner “Synth Master”!


Recoil: What got you started as a vintage synth builder?
Kevin: I Built a Paia Gnome/OZ and 4700/s when I was 14.

Recoil: What was the first system you put together and where did it end up?
Kevin: The first REAL modular I built was the big Moog and Roland (83kgif)
system for Hans Zimmer. It is the WALLS of his studio and it took me two

Recoil: Have you kept any for yourself?
Kevin: None! I have very few synths myself, although I’ve been playing keys
about17 or so years.

Recoil: What would you consider your crowning acheivement as far as:
1. Aquiring a hard to find unit?
Kevin: I don’t acquire. I leave that up to the brokers and owners. I
restore, improve, repair, modify, assemble… but I don’t buy or sell. Keeps
me respectable!
2. Building the most massive systems?
Have you had many struggles to get them working?
Kevin: HAAAA!! Struggles? Ever TUNE a 58 vco synth? Actually, they all worked well
upon powering up, but there’s a lot done before that ever happens.

Recoil: How on earth do you source these units, I mean I’m sure most people
in the know have never even seen a live Buchla or Emu modular. Aren’t they
extremely rare and hard to find?
Kevin: Again, I don’t. And yes, they are hard to find. Harder every day…!

Recoil:What would you consider the most rare system and modules at the
Kevin:Rare doesn’t necessarily mean good or desired. The Ppg modules,
Projekt Elektronik, Wavemaker… all of these are pretty rare. As far as
rare and desired in a major way, the Bode frequency shifter seems to be
requested a lot.

Recoil: What would you consider the most unusual system/module?
Kevin: Buchlas and Serges are pretty unusual from a standard audio/cv
standpoint.There are fewer imposed limitations with those systems. I
personally love the Digisound VCDO as a strange module! The Blacett
frequency divider is another rare favorite.

Recoil: You have put together some massive systems, for Hans Zimmer and
others, do these guys actually use all these modules or are they just rich
Kevin: Both. As far as Zimmer is concerned- He does have a lot of equipment-
no arguement there- but he is very talented and successful, even if he was
to just use it as inspiration, who’s to agrue with his means? It works for
him. It’s much like a painter- he may have 20 greens on the easel, uses only
2 for months, but when he wants the others they are there. As far as your
question- yes, Hans uses the Moog, Roland, Emu and Polyfusion as needed.

Recoil: Do you end up doing alot of maintenance for these people, and don’t
you have a hard time finding replacement parts?
Kevin: No, I do very little maintenance on the systems I’ve built. Generally
they don’t travel. Most systems get new linear power supplies, new trim
pots, new connectors, etc. They are actually very stable. As far as parts, I
have a wealth of suppliers for what I need. I can order Switchcraft jacks,
Moog knobs, semiconductors, pots, switches, just about everything is still
available. Special items like ribbon controller ribbons and custom things
like that are often difficult, though.

Recoil: What system if any are you working on now?
Kevin: I am doing a very elaborate custom synth for Hans now. I have a
repackaging of an Oberheim 4 voice/ mini seq with very complete MIDI for
Mark Isham.There is a very modified 2600 I’m finishing up, with MIDI and
lots of mods. I don’t modify Moogs and Arps and rare synths unless they are
ALREADY drilled up!
Recoil: that sounds like a rather wise decision… 🙂

Recoil: If you could put together any system you desired, which would it be?
Kevin: EEEEEKKKK!!!! I like ’em all for one reason or another. Polyfusions
and Sys-100’s are good later analog designs, though they are pretty tame
compared to a Serge as far as functionality.
Recoil: If you can, name your top 5 systems/modules and tell us why you
choose these?
Kevin: Moog 55- good compliment- good stability. Oberheim 8 voice- Good
sound- well made- Arp2600- well compromised “modular”- good sound, MiniMoog-
just a great sound- great glide- Serge NTO- Great oscillator. period,

Recoil: Thanks for your time Kevin, we hope visitors to this page don’t soil
your Synth jpegs too severly while their busy drooling! 🙂

Back to Vintage Synths Table Of Contents

Back to Main Table Of Contents

File date: April 24, 2010

All slide switches (including transpose and noise) EXCEPT the following:

S8 on later VCF boards
S4, S8 on early VCF boards

All rev VCO boards ok (all switches jumperable), EXCEPT:

S4 (2nd switch from edge) has T3 trimmer wiper hooked to pad.
If this connection is broken, S4 may be jumpered.

Later VCO boards already have S1 jumpered.
Later VCO boards S2 can only be jumpered if traces are cut and R72 hooked directly to center poles of switch.
(Early VCO boards can be jumpered ok for S1 and S2.)

File date: April 12, 2014


Everyone has favorite things.
Here are mine. Some have multiple inclusions.

Comedians: Bill Hicks, Phil Hartman, Bill Cosby, George Carlin

Food: shellfish, fish, good beef, good salads, Tom Ka Kai soup, chocolate chip ice cream, macadamia nuts, passion fruit

Cars: Way too many, but of the ones I’ve owned I liked 85 and 88 Rx7s and the ’67 mustang fastback.

Women: Monica (for oh so many reasons), Michelle Hiatt, LeeAnne Beaman.

Music: much too many, but Beatles, Pink Floyd, ELP, Beach Boys, Steely Dan, Julian Cope… truly, this list could go on for a long time.

Colors: I preferred contrasts of two colors, but if I had to choose one it would be in the violet or blue spectrums. I also have an affinity for orange.

Computers: Apple

Locations visited: Maui, Moorea, Bora Bora

Synths: This is very difficult for obvious reasons, but the Minimoog probably is first.
Seconds included CS80, JP8, OBXa, Arp 2500 and 2600 models.

Favorite experiences: Skydiving, feeding sharks in Tahiti, Sex.. too many.

File date: January 11, 2014

My Roland hiring story:

I was about 22, quite broke and at the time programming my own Apple II graphic adventure game.
I would temp at different companies in the area using a temp agency.
Of those, I had one job where I assembled wiring harnesses in a room filled with only women.
Another was at ITT Cannon, a famous maker of connectors.
It was there I stayed the longest.
I was given a room with a bench and some parts and a much older gentleman would give me a schematic and tell me to make the board.
These boards were all done using wirewrap methods, not printed circuits or soldered.
As it turns out, I was making devices to shut down or monitor huge machines when they got jammed, out of parts or for whatever reason, wrong.
It was the first time I used an IR thermometer.
One you just point at something and get a temperature.

My boss was a somewhat scattered brain, but highly focus-able man named Eduardo Miranda.
In the last 30-60 mins of the day, he’d teach me electronic theory on a blackboard.
I never expected that, but it was nice to be in a class of one and able to ask questions directly. He helped mentor me beyond what I had been learning since I was very young.

ITT was interesting.
It was a secure company with badges required and it was filled with dimly lit warehouses of oily and steamy machines.
Going into the warehouses became a real drag.
While I got to sit by myself and make circuits, I also had to install and calibrate them.
I also had to work on antique computer called a Data General Nova where it had rows of boards about a foot square. Half were originals, half were to control all the machines and again, wirewrapped.
Since the environment was oily and steamy and these boards were filled with thousands of connections, working on this beast became a whack-a-mole type duty.
I was pretty fed up, jobs were easy to get and I left.
Only afterward, did I learn that they wanted to hire me full-time and at a substantial raise with benefits.

My next job was soldering boards.
Again, all women around me.
That was an ok job, but they listened to the oldies radio stations and that meant hearing 1950’s music all day.
Whatever, it was a cake job.

I also was traveling to every musical instrument repair shop in LA.
I visited them all and all turned me down.
One place was called Hi-Tech Electronics. It was owned by JL Cooper, a prominent engineer. But he didn’t fix synths, he had others man the shop.
One of my neighbors at the time was also Michael Basich, a one-time member of Oingo Boingo.
He was already a tech at Hi-Tech.
But the guy I met was named Tim.
Tim had an attitude.
He had an open JP8 in front of him and with a smirk asked if I’d ever worked on anything so complex before, basically laughing at me for his assumed answer.
I told him yes, I had. He brushed me off.

Another was a guy on Sunset blvd in guitar row. (if you’re from Hollywood, you know the area.)
He had an upstairs shop that was tiny, but he secured the repairs from the Guitar Center across the street and had gear up to his eyeballs.
I don’t know if he was on drugs or not, but he couldn’t look me in the eye, was very jittery and gave me the spooks.
Finally he said, if you can fix that, you can have a job.
What he pointed to was a Teac Portastudio.
It seemed that when you put it in a certain mode, two of the meter lights went out.
I told him that was normal. It was in two track playback mode and even showed him it in the owners manual right next to it.
Insulted, he got huffy and I didn’t get that job either.

I also asked Paul Morte who had secured all the repair work for Yamaha.
He basically blew me off too, but admit I only spoke to him on the phone and should have driven down to his place.

Around this time one nite, I was up late programming my Apple.
It was about 10:30PM and the phone rang.
It was my friend Bruce in a semi-panic.
The problem was that he had this friend named Forrest who worked at a newly formed division of Roland called Roland DG, they were about to start exhibiting at Comdex and had no video demo for their new line of monitors.
They were about to display video monitors with no video.
Not good.

Bruce asked if I could make a self-demoing slide show of various pics on an Apple II and get it to them at Comdex the next day.
So I did just that.
I thought, wow… well, yeah I can do this, but how do I get there?
I had no money to fly to Las Vegas.
I begged my mom.
She loaned the money. It was about $80 at the time.
I made a slide show that held about 30 nice display pics, repeated automatically and via a 6502 machine-language routine, I made each photo display the name “Roland” in the corner as an overlay.
It worked fine though I actually made a mistake- I used Roland’s Musical Logo; Roland DG had their own logo, but everyone was still happy.

The next morning I put on my best clothes and flew out to Comdex by myself with only a few dollars in my pocket for lunch, a disk and a return ticket.
By the way, Comdex is huge. It’s covered at the same time in several hotels.
I had to do a lot of walking, but got to the right hotel where Roland had an Apple computer waiting.
The display installation worked well and so went the first showing of Roland DG at Comdex.

As I was leaving, I met Forrest and we began chatting, but his face suddenly went pale.
He said he saw something he’d never seen.
The president of Roland US, Tom Beckman, had excused himself from speaking with some Japanese men and was walking in our direction.
Tom came over to thank me for doing the slide show and asked if he owed me anything.
It was at this point that I knew I had to say something.
I quickly blurted out “Well, I need a job!”
Tom stopped and listened as I explained that I’d already been fixing synths for years, knew digital stuff and could program.
It all came out as one sentence and I felt foolish, but I was nervous and also had a plane to catch soon.
But it was a now or never moment and even Forrest stayed silent as he appeared to witnessing something he’d never seen before.

Tom calmly pulled out a Roland business card with his name on it and wrote down a name on the back: Jimmy Mothersbaugh.
He told me to call Jimmy when I got back in town.

I think I waited until Comdex was over, but called the number and asked for Jimmy.
A man came on the phone and basically said I was hired.
Could I start the following week?
I said goodbye to the ladies of soldering and drove out to Roland on what did turn out to be a new job. They gave me my own tech room, a small tour and introductions to various people.

As it appears, Jimmy was told by Tom to check me out or hire me and Jimmy did just that. I went to the top first and everyone below was intimidated or following orders.

For what it’s worth, Jimmy is actually Jim Mothersbaugh and Devo’s first drummer, brother to the other members of Devo. Through the years at Roland, I’d get to see and hear much of what Devo was doing via Jim.

But that first day, Jim was apprehensive.
I had never given him a resume.
I never filled out a job application.
He told me, “You know if you only last here a short time, it will at least look good on your resume.”
I felt crushed, but knew he didn’t know much about me then either.
I stayed there from late 1984 to early 1988.
For a long time, I was the only authorized service center for Roland DG monitors and plotters. They had none authorized anywhere else in the US.
All the other techs were very happy about this too.
They wanted to get back to fixing synths and boss pedals and hated the DG line and management.
My record of video monitors repaired in one day is 25.
Most were ok, but all had to be unboxed, checked and reboxed.
Many did need legitimate repairs also.

But I got bored at Roland.
Every year they’d release 60-80 new products and we had to fix them in addition to the old ones. Parts were everywhere and stacked higher than anyone could reach without a ladder.
We were out of space. The file cabinet with service manuals was packed.
We also had to install and tear down the Namm show displays each year, which got progressively bigger in production with stages and huge displays.
The years went on and I felt like I was going nowhere there.
Depressed over a recent girlfriend breakup and wooed by a (so called) friend to work at his company and open my own shop, I left Roland.

File date: July 16, 2011

Stop and think about this:

Can you believe you’re alive?
I mean, isn’t this fantastic!?

Think of the universe and how big it is. Empty space filled with rocks.
We’re here on one of those rocks.
But that rock is billions of years old.
For a virtually eternity, we never existed before.
We have no memories of time before us.
And when we die, we cease once more to exist.

The future WILL come, so think that in 100 years, no one may remember you at all.
Just the same way you don’t remember anyone 100 years ago.

But right now… you’re here!
Isn’t that amazing to think about??
You won’t be here later.
Later will be just like this is now to everyone that lives then- normal lives, jobs, crime, leaders, wars and pain.

We exist because we are a positive charge.
The Earth and ourselves have a little more positive charge than negative.
That keeps us going.
But the planet itself is just a spark in time.
Positive charges are easily dissipated.
In the future we will have been a lost civilization.
Unknown to ourselves or anyone else most likely.

So enjoy it while you can, because none of us will look back on any of this.
We’ll have existed, but will be reduced to base elements in the future.
We’ll be nothing.
As we were before and for evermore.

But right now… we are.

Isn’t that amazing???


File dated Feb. 28, 2007

IF… your fvs or eight voice wants to skip a voice, especially voice 1, here’s a possible reason.

In the schematics, pin 8 of flip flops (4013’s) U1-U6 are all grounded.
On the keyboard assigner boards, they’re not.
By grounding pin 8 (short to pin 7), it should work correctly.

IC U1 was the one I grounded. Haven’t tried others.