Alexander Ryzhkov created a small 555 timer-based piano:
Main goal of this project has been creating pretty designed 555 based piano in small form-factor. Many 555 piano are using 9V battery for supply. I use CMOS timer and for timer need only 3V supply.
ChirnoTech/555Piano
[Ross Fish], [Darcy Neal], [Ben Davis], and [Paul Stoffregen] created “the Monolith”, an interactive synth sculpture designed to showcase capabilities of the Teensy 3.6 microcontroller. The Monolith consists of a clear acrylic box covered in LED-lit arcade buttons. The forty buttons in front serve as an 8-step sequencer with five different voices, while touch sensors on the left…
Teensy creator Paul Stoffregen has shared a new project on OSH Park:
The Monolith Synth Project needed to use a large number of these LED lit arcade buttons.
Dimming of the LEDs was required. Initially I considered using this Adafruit 16 Channel PWM board. But the LEDs in these buttons have integrated resistors which require 12 volts, so 16 transistor circuits and another board for reading the switches would have also been needed.
It uses the same PCA9685 chip for 12 bit PWM control on every LED, with mosfet drivers to handle 12V outputs, and also a MCP23017 chip to read the buttons. Every button has a discrete 1K pullup resistor (rather than using the higher impedance on-chip pullups) to help with use in the same cable bundles cross coupling to 12V PWM signals.
Four of these boards where used in the Monolith Synth project:
The project is featured in this Tested video:
From Brian Benchoff on Hackaday:
Before there were samplers, romplers, Skrillex, FM synths, and all the other sounds that don’t fit into the trailer for the new Blade Runner movie, electronic music was simple. Voltage controlled oscillators, voltage controlled filters, and CV keyboards ruled the roost. We’ve gone over a lot of voltage controlled synths, but [Tommy] took it to the next level. He designed a small, minimum viable synth based around the VCO in an old 4046 PLL chip
The circuit for this synth is built in two halves. The biggest, and what probably took the most time designing, is the key bed. This is a one-octave keyboard that’s completely 3D printed. We’ve seen something like this before in one of the projects from the SupplyFrame Design Lab residents, though while that keyboard worked it was necessary for [Tim], the creator of that project, to find a company that could make custom key beds for him.
Read more on the F0 on Tommy’s blog:
Say hello to the F0: a minimalist, analog, square wave synthesizer.
Darcy Neal will lead a workshop in Chicago on building your own synthesizer:
https://www.meetup.com/Solder-Stitch-And-Code/events/238959615/
We’ll learn about some of the building blocks of creating a synthesizer using the 4046 VCO and the classic 40106 CMOS ICs. The 4046 is a well documented and powerful IC that can be turned into a modular synth voice with just a few added components. Participants will learn to solder together their own prototyping PCB, build a circuit on a breadboard from a schematic, experiment with sensors, and learn the basics about how to produce custom circuit boards using design software like Kicad and Fritzing. No experience is necessary, but basic electronic knowledge or a strong interest in synths will be helpful.
OSH Park 