PiezoPreamp v3
Completely redesigned the PCB. Features charge amp with switchable gain, HPF, Baxandall EQ with switchable center, ON/OFF switch with true bypass, DC IN, 9V battery holder, LED mode switch, mounting flanges. Typical current draw of 2mA. Custom enclosure made out of ALU PCBs.
User manual:link
PCB for testing front panel options
Front panels for electronic projects can be created from regular or ALU PCBs. This PCB was designed to test the capabilities of a fab house - to see what can be done and how it will look. It contains text and images drawn on silkscreen, copper and core; holes and cutouts with or without border radius; solid and cross-hatched copper fills and large silkscreen fills.
Github:link
PiezoPreamp v2
Second version of my piezo preamp. Much more professional project using KiCAD, LTSpice, SMD technology and proper PCB design. Features charge amp with switchable gain, high-pass filter, Baxandall EQ with switchable center, adjustable battery indicator, MOSFET reverse polarity protection and ESD protection.
Github:link
Pedal-sized 9V analog mixer
3x stereo IN, 2x stereo OUT. VOL+BAL for each IN channel. Ambler tone tilt for SUB OUT. DC IN 9-18V. Schematics mostly compiled from Small Signal Audio Design by Douglas Self. My most complex stripboard project - showed me the necessity to learn PCB design.
Electrifying a kantele
DIY piezo microphone + appropriate piezo preamp with baxandall EQ (bass / treble) and a volume control for a small cheap kantele for children. Also featuring a "smart" battery indicator.
Klon Centaur + DOD 410
Dual effect pedal. Legendary Klon Centaur on the left with mods to choose between different soft and hard clipping options. DOD 410 Boost on the right. Central switch to change the order of the effects.
Sub oscillator
Sub oscillator to make Behringer Crave sound fatter. Accepts triangle or square wave on the input and outputs a square wave 1 or 2 octaves lower (or a mix between them). Schematic by Carmelo Azzarello.
Carmelo Azzarello's IG:link
ProCo Rat + EQD Talons
Dual effect pedal. ProCo Rat on the right with several mods and clipping options. Earthquaker Devices Talons on the left, also with clipping options. Central switch to change the order of the effects.
Midi thru box
MIDI data from the input is opto-coupled and repeated to five outputs. Featuring 9V thru port. Schematic by Morocco Dave.
Passive tone control
Boosting or attenuating low or high frequencies with adjustable cutoff point and (admittedly not very useful) LED clipping of low or high frequencies.
Expression knob
A simple expression knob I needed for my Empress ZOIA. Works the same way as an expression pedal, just with a knob.