The Tiny TS is a credit card sized (100x65mm) fully open-sourced synthesizer with a 1-octave capacitive touch keyboard.

It has Audio/CV/Gate outputs and 6 synth parameter dials.

The CV’s output 1V/oct and Gate from the keyboard.

With the version 1.1 firmware it now also handles CV/Gate input from a sequencer.

The synthesizer parameter knobs includes: DCO: Coarse pitch and Double. The CV out follows the keyboard and coarse pitch. DCF: Filter peak and ENVmod. ENV: Attack and Release affecting amplitude.

The synth is built on the ATmega328 MCU and is very easy to build as a kit.

The full circuit diagram is as below.

It runs from 6 – 12v (9v battery) but can run down to 3v as well but the CV 1v/oct output is dependent on a 5v supply to the chip.

The PCB is very simple with 1-octave capacitive touch keyboard and a few passive parts.

The BOM for building it:

IC1 – Preprogrammed ATmega328

IC2 – 78L05 TO-92 5v linear regulator

C1 – 100nF capacitor

C2 – 10uF capacitor

C3 – 10uF capacitor

C4 – 100nF capacitor

C5 – 10uF capacitor

R1 – 1Kohm resistor

R3 – 1Kohm resistor

R4 – 1Kohm resistor

CN1-CN3 – 1/8″ Thonkiconn Jacks

P1-P6 – 100K lin Alpha 9mm potentiometers

The PCB

Available at Indiegogo http://igg.me/at/TinyTS and also on Kickstarter

You can order the PCB here:

Order the TinyTS PCB $20

And the files for 3D-printing the case here:

http://www.thingiverse.com/thing:2012211

Building Instructions

1. Get the PCB and all the parts out.

2. Solder the 3pcs 1Kohm resistors.

3. Solder the capacitors as shown in the picture. Mind the polarity of the black 10uF caps.

4. Solder the IC1 ATmega328 MCU (or a socket if you want to reprogram it).

5. Solder the IC2 linear regulator.

6. Solder the P2, P4 and P6 potentiometers.

7. Solder the P1, P3, P5 potentiometers and the Thonkiconn 3.5mm jacks.

8. Finally solder the 9v battery clip.

Done!

Get a 9v battery and plug some headphones in the Audio Out jack to check if it works.

The code

Ok, so I want to code it myself.

This code runs on a standalone ATmega328. You can use it with taped keys or even play the synth directly off the legs of the DIP chip.

But I rather like you to at the least get the PCB for it.