Autumn update: Superpiggie follow-up and “ST4”

Time for a little update after many months of silence on the blog.

Tasty Chips Electronics are still going strong. All the original Piggies have been sold and so we’re going to do a follow-up 😉

The Superpiggy prototype will be a blueprint for this device, although it’s likely it will feature a real VCF instead of a manual filter, along with some other features. The goal is to keep as high a fun-factor as possible, yet also usable as a serious analog monosynth. The product name is not known yet, but there is some idea about the release date: early next year. Also, we will opensource the original Piggy hardware (software was already open), as a sort-of thankyou to the whole Arduino community. 🙂

Meanwhile, the big polyphonic synth project is still ongoing and the prototype is now being integrated with everything on it:
– 3.2″ display
– about 50 knobs
– 4x multi-mode VCF’s
– 4x stereo VCA and mixer
– countless leds and buttons
– MIDI, SRAM, headphone and all other stuff

The ST4 breadboard. Well, part of it..
The ST4 breadboard. Well, part of it..

The SAM3X8E, the micro controller in the Arduino Due, is not powerful enough to control all the analog hardware on its own. A whopping 16 Control Voltages (CV’s) are necessary to control all analog units such as VCF and VCA. So additional PWM IC’s along with output filters were added to the design: these can be controlled by SPI, so the amount of Due pins used there is not high.

Also the display took a huge number of GPIO pins: 21 in total. And all the other devices such as button, potentiometer and led control required many other GPIO pins and analog inputs. All-in-all, the Arduino Due hasn’t got any more pins.. And that’s how we like it: really using the hardware to the fullest, yet keeping it completely transparent for the musician.

Overall, the SAM3X8E and analog electronics now feel like home, just as much as the Atari ST and Falcon once did. This synth, codenamed the “ST4”, will be an ode to those machines of yore. Straightforwardness, directness, fun factor and reliability are the first things we considered. We merge these things we appreciated so much from the early days of computing and computer music with the characteristic beauty of analog audio circuitry; The multi-mode VCF is our own unique design and is very smooth and warm. You’ll love it! 😀