The 555 Noisemusick Kit is a kind-of musical instrument that generates raunchy square wave noise from two 555 oscillators. The circuit is controlled by varying the amount of infrared light hitting the board (like an optical theramin) and injecting the natural resistance of your body into the circuit via four touch points. Squonky fun for the whole family!

Version 2 of the 555 Noisemusick kit is done! Here are the changes from version 1:

1. Larger, friendlier solder pads!
2. An on/off switch!
3. A power indicator LED!
4. Generally improved board layout
5. Oh yeah: a new name!

Here are the schematics and board files:

A larger PNG image of the schematic.
The schematic in Eagle.
The board file in Eagle.

The 555 Timer is one of the oldest integrated circuits still available. It's also one of the few ICs you can buy at the mall! Its hardiness -- and the fact that you can drive a speaker directly from the output on pin 3 -- have made it a natural choice for electronic music experiments in noise since the seventies. The 555 Noisekit utilizes two 555 timers.

The Noisemusick Kit is a lot like the Atari Punk Console, although it was created before I even knew about that project. There's also a very similar schematic in Forrest Mims' excellent 555 Timer Mini-notebook. The touchpads are inspired by the touch sensitive version of Jessica Rylan's BPNG kit.

If you have version 1 of the Noisekit (it's green and says "Noisekit" instead of "Noisemusick Kit"), please follow the Version 1 instructions, which are slightly different.

WARNING : Never plug into headphones! The volume is much too loud and the intensity of the square waves can damage your hearing! Really! The noisekit is designed to be plugged into external speakers, not headphones.

How to Build It

Never soldered before? No problem; it is pretty easy, and this is a very easy kit to put together. Go visit Curious Inventor's thorough soldering tutorial before continuing.

First, place the two 1k and two 4.7k resistors. The colored bands on the 1k resistors are Brown-Black-Red, and the 4.7k are Yellow-Violet-Red:

Bend the leads over on the back of the board:

...then solder...

...then clip. Always remember to hold the end of the lead when clipping!

Next, place the two small capacitors. The 22pF one is blue with a 22J on it, and the .047uF one is yellow. These two are not polarized and can go in either direction.

The 10uF capacitor is polarized: insert it with the long lead in the "+" hole:

Insert the two infrared phototransistor sensors in the spots marked IR. The short lead should go through the lower hole (the one marked with the flat side). Then insert the smaller power indicator LED in the center spot, making sure that the short lead goes in the lower hole.

Important: The infrared phototransistors (detectors) and power LED look similar, but the IR detectors are slightly larger (see photo)!

Plug in the integrated circuit sockets above the IR sensors; make sure that the little notch lines up with the notch on the board. Sockets are used to protect the ICs from the heat of the soldering iron and to make it easier to swap in a new chip if necessary.

The mini stereo jack plugs in at the top of the board. In most cases the jack should fit snugly enough so that you can flip the board over and solder it directly. You may need to use a helping hand clip, or just tack down one of the pins with a little solder on the end of your iron to hold it in place.

Next up is the voltage regulator, which changes the 9v battery supply into a nice even 5V power source. Make sure the heat sink (the metal crown) is oriented as in the photo:

Add the power switch, directly below the regulator:

Next, trim the leads on the battery clip to about 1.5 inches or so, and strip off an eighth of an inch. Solder the leads into the two holes marked "Power"; red is positive, black negative.
The battery clip can be hot glued to the bottom of the board to keep everything together.

Finally, insert the ICs in the sockets. You'd be surprised at how many times people forget this step! One side of the chip has a dot that marks pin 1 of the IC. Insert the chip so that the dot is to the right, on the same side of the socket that has a little semi-circle removed from it.

How to Play

WARNING : Never plug into headphones! The volume is much too loud and the intensity of the square waves can damage your hearing! Really! The noisekit is designed to be plugged into external speakers, not headphones.

ANOTHER WARNING: Only power the noisekit from a 9V battery! If you know what you're doing, you can power it from a 9V DC transformer, but it's always a bad idea to plug things into the wall when you're touching open conductors and completing circuits with your body. Why risk it?

Touch the two left-hand touch points to make sounds. After that, just play around with the thing. Here's the noisekit in action: