Modular "Flunk" Synth


Introduction: Modular "Flunk" Synth

The modular Flunk synth is an Atari punk console with added flange capabilities. It produces a pulse wave using a LM556 Timer.
The flange can be used to process other signals such as guitar via the flange input.
It is powered by two 9v batteries. One powers the console, and the other powers the flange.

This is my entry to the art of sound contest.
Please Vote :)

(This is my first instructable)

The first audio sample is me playing it through a simple sequencer. The second is pure Flunk.

Step 1: What You Need.

1K (2x)
10uF (electronic)
Potentiometers -
500K lin (2x)
100K log
SPST Switch
1/4" Jack
LED (i used a flashing multicolored LED)
9v Battery clip

You will also need a flange pedal. I used a FAB flange pedal, they are only $15.

Step 2: Tools

Soldering iron
Electrical tape
Wire strippers (optional)

Step 3: The Voice

I won't get too deep into this step, but it is the most crucial. Follow the schematics carefully. This will take the most time and patience. I don't have any breadboard, but if it is available for you, test all your connections before you solder it up.

Step 4: Add Flange

Take apart the flange pedal using screwdriver and set aside plastic stomp box (it can be recycled).
Now desolder the led from the board and remove the LED. now add wire were the LED once was on the board.This is so it can be fixed to the enclosure we will be putting it in. I replaced this led with a RGB color changing one(shown below). Then used the Blue-violet one as the Osc On/Off indicator. . now do the same process with the on/off switch, but replace the switch with on of your choosing (i used a spst)

Step 5: Enclusure

Please have fun with this step! The only limitation is your imagination. Find fun and interesting containers or boxes to put your projects in. This is were you get to show your creativity and add a personal touch.
One thing to keep in mind, you will have to drill holes in this to add your knobs, switches, and LEDs. so try to find easy material to do so. (mine is made of plastic)

Here is how I drilled the holes for my enclosure. I wanted it to look professional. also keep in mind playability when deciding on where to drill holes.

Step 6: Put It All Together

Now just attach all the controls to where you drilled your holes. Make sure to use electrical tape to keep your connections from touching each other.



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    Can I use any 556 or must it be the LM556?

    Any chance you can put the schematic online? geocities has closed..

    Hey man,

    I'm pretty sure that the 556 only has 14 pins. Correct me if i'm wrong.


    The synth HAS to be hooked up to a guitar/piano or whatever right? or can it also just be played off an amp?

    1 reply

    it hooks up strait into amp/mixer or whatever.. :)  i suppose you COULD use the flanger as guitar effects, but  it is really just to shape the sound of the synth

    To each other completing the circuit .

    I think I see what you're going for, but the instructable would be better if you provided your own pictures and maybe even a sound clip or video to show how it sounds. I'll be following this if you do

    2 replies

    Actually, there are two sound files posted. and i don't have a videocamera. thank you for you input. This is my first instructable :)