Shruthi-Synthesizer and my "WAVE 1"


It’s nice to see that this long winding project is getting close to completion. I’m quite tempted to get this as soon as it gets out, but I must say a major CPU upgrade would make it even more interesting for further hacking and exploration. Keep up the good work!


I surprisingly very like the beige one !
And look forward to use 3 LFOs. ;))


Yes, I like the beige one as well. Its a nice match with the blue colour. I’m not sure about the led colour, though. It’s hard to judge how it would turn out in real life. The slightly dark red of the delete button looks great together with the beige and blue, but the led colour is more of a bright red/orange type…




Thanks people! :slight_smile:
We didn’t really discuss LED colours yet. It’s tricky because you don’t get everything in every colour… so some compromises will have to be accepted.


I hope you will design the UI too :slight_smile:


The Pannelboard

Hey everyone. The pannelboard is ready. I’m now reviewing circuit diagram and PCB layout. If there are no errors then it is ordered together with the filterboard. Andre is still a little on the case. The end result is very tense.

Pic1: Pannelboard PCB
Pic2: Pannelboard circuit diagram
Pic3: Pannelboard 3D view

I’m still working on the software. For example, the cut and loop function for samples. By the way, the 8Bit samples in combination with the fixed oscillator waveforms sound totally cool. Here is a small example: Oscillator1 plays a chorus sample and oscillator2 a sinusoidal waveform with slight frequency offset. Echo effect also comes from the degenerator.

Sound: Choir from Degenerator

Pic4+5: Osc1: choir-samplel and Osc2: spezial sine-waveform

Greetings from germany. Rolf


The filterboard is now ready. Filter PCB and Panel PCB has been ordered in china today. I hope the Santa Claus brings them on time for the Christmas Eve :wink:

To the filterboard: The filter is designed as a two-channel 12dB tifpass / highpass / bandpass filter.
It has two input for the DAC outputs of the CPU and an external stereo input for Audio source.


What’s the purpose of the diode network in the filter? Looks like rectification and distortion. The resistor in parallel bypasses the diode network to set the desired balance between the clean signal and the distorted signal?
What’s the benefit compared to the simple 2-diode distortion circuit found in many guitar pedals (one diode to GND and another anti-parallel)?


Hi , no , this controls the amplitude of the resonance (Q). It is not for distortion - simply an automatic gain control for the resonance .


Short info … The ordered Pannelboard and Filterboard are only delivered on 26th December. So we have to be patient. The while I still work on the software. For sample recordings there is now a cut function to cut out disturbances or the other things.

On the picture: The inverted area between A and B is deleted by pressing the “Delete” key. The 6-digit digits above the knobs show the current sample address of point A and point B.

Now … there is a new soundtrack from the DE-GENERATOR of soundcloud. The CD is not yet in the trade :wink: Have fun …

DE-GENERATOR Soundtrack 7

Greeting Rolf


Sorry if this has been asked (It’s a long thread) but what are the plans for this? Kit? Boards?


Kit and Boards!


1;) easy kit - all PCB’s are soldered and tested - you only must build it into the case
2:) and complete DIY kits .
Actual i have order the last 2 PCB’s for the DE-Generator . Should come on 27…28 .12 .2016.
If all works - than the electronic is ready .


The PCBs for Filter and Pannelboard have now arrived from China.
Now we will solder the PCBs and test them.





It’s done…

Just before the year change, I can announce that the DE-GENERATOR electronics ready
and everything works. The next days and weeks we will still be at the housing and software.

Pics: The new DE-GENERATOR and old the prototyp


Looks great! Happy new year!


Oh man that was a hard trip . We build now since janualy 2013. Damnd this are 4 Jears.
The PCB’s works all on the first try - we have a few smaller errors but only on the silkscreen .
So the three pots on the filterboard miss it’s values - or 2…3 connectors don’t have a lable for the direction . But - and this is the important thing - the PCB works and this on the first try .
So it is a nice jear end and we hope we will finish in february 2017 . Than it’s De-Generator time .
Thanks all followers on this thread, and a happy new jear .

Special thanks goes also to Olivier for his help and , i have learn a lot from him . Without the Shruthi
, open source and open Hardware , i don’t think that we had realize the De-Generator.

So hopefullly we present next a new and nice music Instrument.
We will also set the software open source , schematics are free and specially we will describe the filter design/interface and, how to implement/design a new filter.

De-Generator had now a standart filter - but - why not a Polivoks for the De-Generator - or
a ladder , or the SMR4. or , or , or .
The Interface is nearly simila to the shruthi - so it is not a big deal …

I wish all a happy new jear .




Great work, both of you! It must be very satisfying to see such a long-term project coming together. I truly admire your dedication over the past few years.

Maybe you should get Devo to help promote it :wink: