While working on the Multiwave Mega developement, I got stuck and almost gave up on the whole project, so I decided aim my attention elsewhere for a while to regain my sanity... I figured that the Quantum Defrakulator drone synth could use a few more features. After all, the first version was as barebones as possible.
So here's the new MK2 version. :)
PCB avaliable now in the webshop and complete kit avaliable from www.musikding.de
I plan on releasing a few more "normal" pedals going forward, so stay tuned.
Here' alittle bit of news. :)
New DIY project release!
Today it's the release of a new DIY project - the 1985 Guitar Synth
Upcoming DIY Projects
Some people would probably not agree with the disadvantages I listed since I've seen people go crazy with complex build using IC chips and even SMD components on Manhattan style builds.
I try to keep the distance between the middle of the pads to around 8mm-13mm so that the components are tight together, but not too close that is becomes too fiddely to work with. After the pads are made I like to pre-solder all the pads - just fill them up with a decent amount of solder. Now the board is perpared and it's time to start soldering in the components. Cut the legs of the component alittle shorter (check the distance against the board) and bend the legs alittle to make small "feet". Reflow the solder of the pad and put the component in. Hold it and let it cool for a few seconds, then do the other side. As you go along there will often be several components connected to the same pad, and then it helps to apply some new solder to the pad when adding more components. I find that it's best to start in the upper left corner and work your way through the board from left to right.
As you can see in this example, the layout follows the schematic with a few minor changes (just to have the pads lined up nicely). I normally just use pen and paper to make the layouts, but I wanted it clean and easy to read for this presentation.
Parasit Studio originals
I made two original designs specifically for Manhattan style of building. :)
Even through it might seem like a step backward, it's been really fun to make something different for a change. Expanding my bag of tricks, learning and challenging myself to come up with new stuff is what keeps this hobby fun and interesting for me. I haven't seen many pedalbuilder using this technique and I was inspiried to try it from a great HAM radio guy that I follow on youtube.
Check out his channel: https://www.youtube.com/user/w2aew/
I have not made a proper demo yet, but here are a couple of examples.
I hope you like it! :)
I'm happy to announce two new projects coming soon, summer sale and more!
It's been a long time since I posted anything. I've been very busy lately, working, touring and doing other projects. It's been hard just to keep up with the emails i'm getting every day, let alone work on new stuff. But in the last couple of week I've finally had some spare time, and I've managed to complete a couple of projects that has been brewing for a long time. I hope you find these interesting. :)
More into coming soon on the new projects!
I expect about 5-8 weeks until release.
New PCB versions released!
To celebrate these news I now offer a 10% discount in the webshop.
Just enter the code "summersale" at the checkout. Valid until 5/7.
That wraps up this long overdue post. I hope everyone out there is having a great summer.
Cheers // Fredrik
It's time for another part of the CMOS Workshop series. :)
This part will be about octave up circuits (aka frequency doublers).
1. XOR gate (CD4070)
The CD4070 is ideal for this purpose and require very little extra components.
XOR logic: For the output to go high, both inputs needs to be at a different state
By connecting our square wave to both inputs and delaying one of the inputs slightly, there will be a brief moment when the inputs are in different states. At this moment the output will go high, thus creating a short pulse wave at the output every time the input goes high or low.
The delay is made out of a simple RC filter. It will round out the square wave, so that it takes alittle longer for each transition to cross the switching threshold of the logic gate.
Lets try this circuit on the breadboard. Remember to always disable all the unused inputs.
Here we can play around with different values for the RC filter. It will change the width of the pulses and the character of the sound. For C5 (C1 on the schematic) try a 4.7nF - 47nF value. For R5 (R1 on the schematic) try 10K-500K. In the 1B example I've replaced R5 with a trimmer and for convenience I chose another gate. The top greyed out part is the gainstage and schmitt trigger front end from the CMOS Workshop part 2 so you will have to check the other component values there.
Notice that the pulse width can get too narrow or wide for the octave up effect to work. As a rule of thumb you don't want the pulses to be too narrow because it will sound bad, and you don't want the pulses too wide because then it won't track properly on the entire fretboard.
The B schematic is just another way of doing the same thing. I just moved the inverter to the input insted.
4. NOT gate (CD4069)
There's one last version I would like to include in the article, similar to the schmitt trigger one, except that it uses regular inverters.
That's all I had for this part.
I've given some examples of how to make frequency doublers with edge detector circuits using at least 5 different CMOS chips (if you count the schmitt trigger variations). Which one you choose will probably depend on the rest of the circuit you are making. Maybe you already need a schmitt trigger chip in your circuit to do other functions, then example nr 2 is better because you will still have 3 gates left over (if using a CD40106) insted of adding an xor chip to only do one thing. Personally I prefer to keep the chip count as low as possible even if it adds more components. It usually takes less time to solder a few extra resistors and caps then having to solder another 14 or 16 pin chip (which also takes more space on the PCB). It's all about convenience.
As I've shown, there's usually several ways to do the same thing when working with CMOS. Remember that we're dealing with 1's and 0's, so no matter which chip/method you use it will basically sound exactly the same (granted that the pulse width is equal of course). Same goes for the octave down methods in the previous part. However, there is a clearly sounding difference between edge trigger or rectifier doublers, or PLL VCO frequency doublers (as used in the Into the Unknown guitar synth) which I will cover in a later part.
But next part will be about oscillators and LFO's.
We will breadboard some fun stuff, as I've promised :)