Build it yourself from a kit!
The Business Card Synthesizer is a tiny synth that can be connected to a Business Card Sequencer, other synth gear, or played by itself.

These fun little kits were introduced at Knobcon 2018 as a build workshop. Now you can get your very own.

Headphones can be connected directly to the output of the synth, and there are plenty of knobs to play with, so you can easily make noises anywhere. Great for learning about synthesizers!
We send you a board and a bag of parts so you can build it yourself. Difficulty level = medium (it's all through-hole, but some of the soldering is kind of small). The kit includes the PCB, preprogrammed microcontroller and all required parts to build kit.

Features:
Pulse, square, triangle, and sawtooth waves
Glide
2 LFOs with pulse, square, saw, triangle and ramp shapes
Attack / Decay
Low-pass filter
Sample and Hold
Manual gate trigger (can be locked on)
Course and fine-tune controls

Controls:
S&H Button: Enables Sample & Hold, which disables the external CV IN jack and uses LFO1 and LFO2 to determine oscillator pitch. LFO1 sets the sample rate (SHAPE is ignored for this), and LFO2 is the wave that gets sampled.
GATE Button: Manually turns on the gate so sound comes out of the synth. This control is momentary, but you can latch it on by tapping the S&H button while holding the GATE button down.
COARSE TUNE: Adjusts the pitch of the oscillator up or down in large increments
FINE TUNE: Adjusts the pitch of the oscillator up or down in fine increments
SHAPE: Changes the shape of the wave produced by the main oscillator (VCO). Turning this control fully CW gives you a triangle wave. Start turning it CCW takes you through sawtooth/ramp, then at about the 12:00 position you get a square wave. Conti