MonoMiK

If you want to use my circuit designs, feel free, this is an open project - at least for the hardware. Get the schematics for all built and tested units here.

If you intend to build the whole MonoMiK, i have to warn you that i might not release the firmware of it as open source. All the firmware of my DIY projects are a lot of work now and i still didn't finally decide if i want to use this in a commercial way some day. Besides this, there exist nearly no documentation and everything needs a lot of cleanup. So we'll see what happens. At least i plan to release some minor projects completely open, so there will be at least a very simplified version of the MonoMiK control computer available.

Besides this, it is no problem to use all those modules in modular synthesizers. They are designed to run off +-15V, some modules also need +5V for digital control circuitry (just the VCO mixers do so because of the TWI I/O chips), if they need +-5V, they generate this themselves. There is really no magic about those circuits, you can hear how they sound in the videos i create from time to time, the electronic design might include some nice tricks from time to time, but all in all, it's just standard synth electronics like you can find lots of it in the web.

The board layouts provided for the modules are no real board layouts for manufacturing those modules, even if they might look this way on the first sight. I didn't plan to provide those layouts, but on request i will provide them - but keep in mind that they are provided "as-is". I just create those rough layouts as helpers when soldering the boards together on veroboards. The VCO layout is incomplete and horrible, but i just remove one bug. There are missing 4 resistors for the front panel potentiometers and the power lines are missing also.
As the request for the layouts came right after the completion of the VCO, i created the VCF layout a bit more carefully, so this reflects my board nearly perfectly. As i had to add a resistor after soldering together (R142 on the diode ladder filter), this looks a bit strange in the layout. Besides this, the backplane connector is not wired and the front panel potentiometer is not verified if it's the right direction.

So keep in mind that you should not put together the modules using those layouts without thinking about what you are doing. Use them for components placement and wiring between the main components, ignore front panel knobs and backplane connector! Always have the schematics handy to verify what you are doing. And always do a quick check before placing the ICs and so on the board and power it up:

• Check if you don't have shorts between the power lines
• Check if the polarity on all ICs is correct for the power lines
• Do some checks of the wiring - as many as you want

After building a module on veroboard, don't panic if it doesn't work on the first try, this is quite normal. If you created a module where everything works perfectly on the first run, you did a really perfect job with a lot of concentration. But in most cases, you forgot a simple wire or have a bad solder joint or anything else. You need to understand the circuit and use the oscilloscope and multimeter to debug it.

You may ask me - but please understand that i don't have unlimited time and so might not be able/willing to help you. I get a lot of very very basic questions all the day. I always try to help here, but if i see that someone tries to build a whole synthesizer without knowing some semiconductor basics, i will try to get out of this as friendly as possible :)

On the next pages, the modules are described in order of their build dates. All modules announced there have been completely tested and found to be okay. Schematics are released if everything is okay, i don't want to release buggy schematics. So everything you see here should work and behave as desired.

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