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Showing posts from 2014

Soldering Fun

From Midi to Control Voltage I decided to start my project with the Midi2CV functionality. As the mios32 on stm32F4discovery board can already receive midi events from USB it was best to try to turn those into control voltage first. Support for traditional midi hardware input can be added later. The CV output schematic is heavily based on Midibox AOUT_NG board  but I made some tweaks because of component availability etc. For example the DAC voltage reference on my board is Maxim's REF02 because I happened to have one around. I also left the other half of the circuit out for now as I don't need 8 cv outputs (yet!). I have done lots of soldering during the years but always with the good old through-hole type components. Even a left-handed bass player can easily work with those. Unfortunately I was only able to find the MIOS32 supported d/a-converter MAX525 in a modern super tiny SSOP package. The options were to use another DAC-chip and write a driver for it or learn t

Starting point

Background Got my interest for electronics tweaking back after a long pause. In the past I have built a tube guitar amplifier, an analog synthesizer and lots of other more or less audio related things but haven't had much time or interest for soldering lately. After some serious thinking I couldn't come up with anything new so decided to do some improvements to my old analog synth built back in the university days on last decade. As I have been writing embedded software for living for some time now I thought it would be a cool idea to add some digital awesomeness to it. The synth. Looking very professional. Wood makes it sound more natural! The device is based on the  Mad Mouse  DIY project. (2xoscillators, filter, amplifier and simple envelopes.) In addition to the analog part the wooden box contains a MIDI to CV board based on  Marc Bareilles work . So basically it's a monophonic analog synth eating midi and outputting really pleasant old school synthesizer sou