DIY Niceties for the Casio CZ-101

[Thomas Henry]

Hello Gang,

I thought I would share the results of a recent project in case anyone hits the jackpot while trolling the yard sales, thrift stores or pawn shops. Here's the deal. Some years back a guy gave me a Casio CZ-101 synth free of charge. As it turns out, he had let the batteries leak all over everything which made a royal mess inside; the externals looked like new however.

I was able to successfully clean up the leakage, and it plays great now. With that under my belt, I decided to do some mods to make it even more useful in the studio. They are:

1. Replace the dull unlit LCD with a brilliant and crisp OLED display.

2. Replace the D-cells batteries with a 9V battery. You'll see why in just a moment.

3. Come up with an DC power adapter. This was not as obvious as it might seem from a mechanical point of view.

4. Finally, figure out a way to save multiple patches, rather than the paltry sixteen patches the stock unit provides for.

Here are the details should you want to follow suit. The stock LCD unit is so dim that I had to always keep a flashlight nearby in the studio just to read it. That's not very convenient, and is even worse if you have cataracts like I do. Well, it turns out some chap did the homework on this and found an OLED display that is the exact mechanical fit for the stock display. Best of all, the color is yellow which matches the various legends on the case nicely. The first picture below shows the entire beast, while the second is a close-up of the display.

The desired upgrade display is the W162-XLG. I found it at Mouser. The price was a hefty $67 dollars after tax and shipping, but remember I got the CZ-101 for free so was already ahead of the game.

Here's a link to the basic YouTube instructions from the kind fellow:



He didn't explain how to get access to the display (which is buried under several layers of PCBs), but I found another YouTube link with the needed dope. In particular, this guy shows how to pull out the old display without completely disassembling the synth:



Normally, pulling the case apart would be a piece of cake following his instructions, but not so in my case. Seems two of the case bolts were corroded over from the battery leakage and the Phillips slots were eaten away. That these lie at the bottom of deep tunnels added to the difficulty, i.e., there was no access to cut a new flat blade screwdriver slot. I almost gave up, but then decided to risk drilling the heads away completely. It worked, and I was back in business! Normally, though, removing the back cover should be easy.

Now it was just a matter of desoldering the connections to the punk display and moving them to the new one. As mentioned, everything fit perfectly, and the OLED display worked right off the bat.

One thing you might like to know, however. As mentioned, the display looks beautiful. However, if you rapidly scroll through numerical values you might note an occasional random pixel flicker. This is not all that bothersome to me however. The advantage of having a bright display far outweighs an occasional pixel flicker when changing values quickly; it's not like I'm constantly punching in values anyway. I suspect this is due to the difference between how the stock display (a garden variety and slow LCD) compares to the much speedier OLED. Anyway, as mentioned, this upgrade is definitely worth it.

Next up was taking care of the battery business. The CZ-101 was manufactured back before non-volatile flash eeprom was common. So, Casio opted to use RAM. So long as batteries are present, the memory is present. But additionally, the batteries being D cells can also run the who shebang for six hours or so. Well, given the price of those batteries, that idea is a stinkbomb.

So instead, I swapped in a 9V battery in lieu of the D-cells with the idea being that it would only be used to maintain memory, not run the synth. Instead, in the studio I'll always use an DC power adapter, the battery is there only to hold the RAM contents when the unit is switched off. The drain on the battery when used in this fashion is 0.01 mA, and so the battery should last not far from its shelf-life.

So what happens if you forget to plug in the DC adapter and are running off of the 9V battery only? Well rather pleasantly Casio worked in a subcircuit which monitors such things. The red power LED will begin to flash when you're running on the 9V battery only and the voltage is dropping perilously low; that is your reminder to plug in the DC adapter. Incidentally, Casio also designed in a switchable automatic power-off function; it will shut everything down after 5 or 10 minutes of no key action. This is annoying in the studio, so I disable it and just keep the DC power supply plugged in while recording.

If you're interested in how the internal power circuitry works, the complete schematic of the Casio CZ-101/1000 is available here as a PDF:

http://www.burnkit2600.com/manuals/CASI ... 00_SRV.pdf

The third picture below shows how I cemented a 9V battery holder inside the D-cell chamber. Making the change is just a simple matter of desoldering the red and black wires and reattaching them to a 9V battery clip. But if you'd like more detailed info, check out Alan Gary Campbell's article, "CZ Mods," Electronic Musician, August 1986, pp. 51-62, which also describes a number of other mods (none of which appealed to me, though).

Now about the DC power adapter. The Casio manual specifies it to be 9V DC, at 850 mA. I'm using an old wallwart I got for a dollar some years back from All Electronics and it works just fine. The CZ-101 contains further capacitors and regulation circuitry to clean up the power. But here's a non-obvious aspect to it all. The barrel jack on the CZ-101 expects the plug to be of the dimensions 5.00mm outside diameter, and the inner pin to be 1.6mm. Back then, this was known as a size J connector and was reasonably commonplace; not so now! I had to hunt around on eBay before I eventually found a guy clearing out some old Radio Shack stock from that era. I got a two-pack (RS 274-1570) for six bucks and soldered one to my power adapter. See the fourth picture. You'll note that I printed and affixed a sticky-back label to the adapter, identifying it as for the CZ-101, and also listing its electrical characteristics as well as the fact this is a center-negative affair. I do that for all my wallwarts so that I don't accidentally plug in the wrong one.

Speaking of which, I'd like to invent a time machine, travel back in time and neuter the parents of the person who invented the wallwart...

The CZ power adapter has fooled many people, judging by comments on the Web. Using the more common 5.5mm X 2.1mm connector leads to an intermittent power connection, and the battery will be drained quickly when forced to take over. So, be sure to get the right size.

Last of all, I wanted a way to save large collections of patches, not the feeble sixteen within the CZ-101. In fact, I started designing a patch storage unit around a PIC, until quite by accident I stumbled upon the following:

https://www.pluginboutique.com/product/ ... -VirtualCZ

This is virtual CZ emulator for Windows or Mac, which in itself is pretty cool. But more importantly, the designer also worked in the SYSEX protocol (which is kind of weird) for the Casio. Thus, I now have the ability to swap any number of patches back and forth from the CZ-101 and a laptop. In effect, I have enormous storage capability now. And the Virtual CZ software only costs $13, so besides being way more powerful than my proposed PIC based librarian, saved me countless hours of labor. I really recommend it as an integral part of the CZ-101 setup.

Finally, I was so pleased with the results of everything here, that I also applied the treatments to my full-sized CZ-1000 which I bought back in 1984 or so. Hence I now have two CZ's in the studio. If you're not familiar with these, you should know that they are particularly good at intense hard sync effects, as well as bass, flute, brass and accordion type sounds. And as a retired mathematician, I'm still fascinated by the clever approach Casio undertook in coming up with Phase Distortion for these synths. That method not only sounds great, but is aesthetically appealing from a mathematical point of view.

Well, that's a long-winded post, but I hope someone might find something of use here.

Thomas Henry

[Spanningtree]

Awesome post, thank you for sharing. Makes me want to replace the 101 I had years ago but the prices are typically pretty high. Need to hit more yard sales.

[autodafe]

Thansk for sharing I want to to LCD replacement on my 5 Euros (yard sale, yes!) Casio CZ-1000 but I need to solve other problems first (very low volume for sounds but very loud noise out of the machine

[ashleym]

Don’t apologise!! I have a CZ5000 and I’ll read this properly to see what I could apply

[SphericalSound]

I would love to dig into the FM vs PD differences and the mathematical elegance of the Casio approach. I still doesnt grasp the FM vs PD difference apart than PD is a subset of FM... Any inspired links digging into that welcome.

Also, I was thinking in getting the Virtual CZ... the plogue guy has super interesting videos and is a nice way to support him. And frankly, his vsts rocks!.

Finally, Thomas, how do you find it sonically versus the real thing?

[synthetek]

NIce, found one for $40 recently and did the screen upgrade. I used a Vishay OLED-016N002E-RPP5N00000 it was like $8.99 at arrow. Still trying to figure out how to DIY a stand alone patch loader like the CZPL.

Part #s for Vishay OLED for CZ series
OLED-016N002E-RPP5N00000 - Red
OLED-016N002E-GPP5N00000 - Green
OLED-016N002E-WPP5N00000 - White
OLED-016N002E-BPP5N00000 - Blue
OLED-016N002E-LPP5N00000 - Yellow
You can also use Winstar WEH001602E and Raystar REC001602E

PXL_20201020_052229172.jpg

PXL_20201020_055554494.jpg

[Bjarne]

The price for the Virtual CZ was just increased 72 Euro's. Ouch.

[synthetek]

Edisyn is free https://github.com/eclab/edisyn

[Jaytee]

If anyone wants a challenge....

IMHO the holy grail mod for CZ-101 (and presumably the other CZ synths) is a data wheel or knob. Unlike a lot of 80s digital synths, programming a CZ is actually really easy and straightforward.....but it’s still a PITA because everything relies on the two up/down buttons. Very tedious.

It should be possible to turn encoder pulses into spoofed button presses—adjusting parameters with a knob instead of a million button presses would make life a lot easier. I sold my CZ-101 a few years back or I’d have this mod on my to-do list. I still hope someone might make it happen, I’d pay the inflated prices CZ-101s go for if it did.

[Thomas Henry]

Thanks everyone for your suggestions and comments. It looks like I paid way too much for a suitable display, but to balance things out got a hell of a deal on the VirtualCZ.

For anyone else who stumbles upon this thread, Synthetek can you confirm two things?

1. Did you find the Vishay display was a perfect mechanical fit?

2. And, have you noticed occasional random pixel flashes when scrolling rapidly through data values?

As for the Edisyn software as an alternative, I've not been completely successful in making it work satisfactorily under Linux. Some of the functions appear to work, but others (such as receiving a patch from the CZ-101) don't. It sounds like the Windows version may be even more problematic. So perhaps this software is best suited for Mac users. Anyway, the display artwork is not all that appealing, aesthetically.

On the other hand, the VirtualCZ editor is gorgeous, and works very well. I'm using it on Windows 7, and didn't even have to read the manual to make everything perform properly right off the bat. But there's no way I'd ever pay 70 dollars or 70 Euros for it! As mentioned, I got it for $13. Perhaps it goes on sale from time to time, so might be worth watching out for.

The layout for VirtualCZ is beautiful, and the fact that every parameter is brought out to slider controls makes it a snap to program the CZ-101 with absolutely no menu navigation or numeric twiddling involved. It feels just like programming an ARP Odyssey. One particularly nice feature is that it's possible to run all the envelope generators as thought they were ADSRs, i.e., reduced to four steps instead of the more extensive 8-step EGs of the CZ-101 default. The point being that sometimes you don't need all that power and will be happier with the reduced arrangement.

And, oh, it also comes with a couple hundred sample patches of which I've found a bunch that are truly magnificent.

So my conclusion: I wish I'd known about the Vishay displays, but am happy I got the VirtualCZ software on sale. This all makes a nice package now for my studio.

Thomas Henry

[synthetek]

For anyone else who stumbles upon this thread, Synthetek can you confirm two things?

1. Did you find the Vishay display was a perfect mechanical fit?

2. And, have you noticed occasional random pixel flashes when scrolling rapidly through data values?

The Vishay parts I listed are exact fit, the original screws hold them in, I have not noticed any pixel flashes but I have also not used it much since installing the screen.

[mckenic]

Thanks for the OLED recommendations! Always loved my 101 but have not played it in years. Might be a good excuse to upgrade and get back in to it!

[a.d.a.m.baby]

Thanks Thomas
since you now have TWO CZs in your studio, you must try panning them hard and detuning each in opposite directions (assuming you loaded the same patch in each) - it's an absolute wall- of - sound!

A few other tricks here
http://mezzoauto.blogspot.com/2020/12/m ... z-202.html

I've tried in the past the 9 volt battery trick, but I found it actually ran down surprisingly fast. I'll review your info and take another look at this, because having only volatile user memories is a real PITA. My two CZs are controlled by Midiquest, which does a great job, but it would be nice to have some favourite voices ready to go without turning on the computer.

[a.d.a.m.baby]

If anyone wants a challenge....

IMHO the holy grail mod for CZ-101 (and presumably the other CZ synths) is a data wheel or knob. Unlike a lot of 80s digital synths, programming a CZ is actually really easy and straightforward.....but it’s still a PITA because everything relies on the two up/down buttons. Very tedious.

It should be possible to turn encoder pulses into spoofed button presses—adjusting parameters with a knob instead of a million button presses would make life a lot easier. I sold my CZ-101 a few years back or I’d have this mod on my to-do list. I still hope someone might make it happen, I’d pay the inflated prices CZ-101s go for if it did.

This has been done in the past, so long ago I can't remember where I saw it, but it still doesn't give you smooth (-ish) parameter changes: the nature of the CZs architecture causes an audible step with every integer value change if a note is being held down. (This stepping sound is actually quite interesting in itself, and differs between parameters). But I agree, it would speed things up quite a bit for front panel programming.

[Thomas Henry]

Hi a.d.a.m.baby,

Thanks for the note. Your duo-101 system looks great, and the stereo idea is fabulous.

Regarding the 9V battery, I measured the current draw just now. On my CZ-101 it's 0.017mA, and on the CZ-1000 it's 0.018mA.

I'm using Amazon Basics batteries. These were tested at https://rightbattery.com/980-9v-amazon- ... tery-test/ to give 481mAh at 50mA load. So, carrying out the division gives a theoretical lifetime of a little over three years. This is not far removed from the normal shelf life.

So my plan is to change them (or at least check them) once a year or so. And of course, I'm using the VirtualCZ software to back up all of my patches to disk for security anyway.

Thomas Henry

[Thomas Henry]

One more thing, friends, that I keep forgetting to mention.

I had the CZ-101 all apart for some two or three hours while replacing the LCD display with the OLED display, obviously with the battery disconnected. Despite that, after reassembling everything and installing the battery again, believe it or not, the memory still held my custom patches!

Pretty clearly there's some sort of super-capacitor in there, although I haven't taken the opportunity to spot it on the schematic yet. That it still holds a great charge after some 35 years is a marvel! The manual indicates that a person should change batteries in under 10 minutes to preserve the volatile memory, but as mentioned I was unpowered for over two hours and everything held just fine.

This, among other things, makes me appreciate that the essential design and manufacture of the CZ-101 really was top-notch.

Thomas Henry

[Jaytee]

If anyone wants a challenge....

IMHO the holy grail mod for CZ-101 (and presumably the other CZ synths) is a data wheel or knob. Unlike a lot of 80s digital synths, programming a CZ is actually really easy and straightforward.....but it’s still a PITA because everything relies on the two up/down buttons. Very tedious.

It should be possible to turn encoder pulses into spoofed button presses—adjusting parameters with a knob instead of a million button presses would make life a lot easier. I sold my CZ-101 a few years back or I’d have this mod on my to-do list. I still hope someone might make it happen, I’d pay the inflated prices CZ-101s go for if it did.

This has been done in the past, so long ago I can't remember where I saw it, but it still doesn't give you smooth (-ish) parameter changes: the nature of the CZs architecture causes an audible step with every integer value change if a note is being held down. (This stepping sound is actually quite interesting in itself, and differs between parameters). But I agree, it would speed things up quite a bit for front panel programming.

Neat! I’ve seen a similar mod on another synth but not the CZ. And yeah, while real-time parameter changes would be amazing, just speeding up the programming is the real goal. I got the VirtualCZ plug-in mentioned elsewhere in this thread a few years ago and sold my real CZ when I realized how much quicker it was to program the VST.

[rst]

Sorry for the offtopic but... the wallwart must be originally from one of these https://en.wikipedia.org/wiki/Atari_Jaguar