GranulArduino
Introduction
This module is based on the Auduino project by tinkerit in 2009 and Notes and Volts in 2014. In my version, I added support for CV inputs on all knobs.
It’s a simple granular synth using grains based on two triangle waves. You can find the original resources in tinker.it’s Google Code archive:
- https://code.google.com/archive/p/tinkerit/wikis/Auduino.wiki
- https://code.google.com/archive/p/tinkerit/downloads
This my first build done with the help of Makerlab Electronics who sponsored the parts for the build. They are a local electronics shop here in the Philippines who carry Arduinos and 3D printers among a lot of other things.
Build
Disclaimer: This article is not intended to be a tutorial. It is only my documentation on how I built a synth module for myself.
I do not have formal training on electronics. Most of the time I decide on things by trial and error. There will probably be better ways of doing things but feel free to build this yourself and get inspiration for your own designs!
Bill of materials
| # | Value | Type | Part # |
|---|---|---|---|
| 1 | Arduino Nano | Arduino | |
| 5 | 100nF | Capacitor | |
| 2 | 100uF | Capacitor | |
| 2 | 220nF | Capacitor | |
| 1 | 4.7uF | Capacitor | |
| 1 | JST_BUS | Jack | PJ398SM |
| 1 | JST-XH 1x03 | Socket Connector | |
| 1 | IDC 2x05 | Socket Connector | |
| 14 | 100K | Resistor | |
| 8 | 1K | Resistor | |
| 1 | 2.7K | Resistor | |
| 1 | 220 | Resistor | |
| 3 | 10K | Resistor | |
| 9 | 10k | Potentiometer | RV09AF-40-20K-B10K |
| 3 | L7805 | Regulator | L7805CV |
| 2 | TL074 | OpAmp | TL074BCN |
| 2 | TL072 | OpAmp | TL072BCP |
| 1 | ADS1115IDGS | ADC | ADS1115IDGS |
Schematics
Here are my schematics for v1.0. Click on the images for a larger view. You may also download my KiCad files if you want.
Code
My Arduino code for this can be downloaded from my Github page.
I had to do some input scaling to compensate for my analog circuitry. I can’t seem to get the full 0-1024 range. This should do for now, but I plan on fixing this in the next version.
Demos
Conclusion
There is so much more I can improve in this build.
Range of CV input can be scaled down to 5V to allow for wider octave control. Usable range of each CV input can be fine tuned.
I hope to build a more complex granular synth using wav or MP3 files in the future, but I still have so much more to learn before I get there. Till the next module!
Let me know if you’ve built it! DM me on Instagram @benjiaomodular.