Brilliant Arduino Sequencer

Spotted this fantastic Arduino based synthesizer / sequencer on the make blog this morning. The official website for this project can be found here. The links include video of the device in action is well as code and schematics in case you wanted to build your own APC (Arduino Punk Console) not to be confused with the 555 Timer based Atari Punk Console (APC) which is an entirely different but totally fun weekend noisemaker project. Be sure to check out the rest of their website Beavis Audio as they have lots of other cool audio devices and effects.

I have spent hours playing around with the Arduino board since I purchased one almost a year ago today. Our first instrument an optical theremin we called Fotosis No. 001 used one to control various effects. The possibilities this simple USB cross platform micro-controller presents are almost limitless (Well not really limitless) and I love to see what lots of people around the world is doing with this great tool. I also like the fact that this device is getting the attention it deserves from websites like Make so more people can be turned on to its potential.

-J

Modification to the Wacky Sound Generator

Here is a little drawing of a modification you can add to the music from outer space wacky sound generator.

This was one of the first noise making units I built. Its a really simple fun little project that produces lots of cool strange sounds and has the potential to be modified in lots of interesting ways. Here is a post we did earlier regarding our own WSG housed in a cardboard enclosure.

How does this mod work? Well one of the first things you learn when studying electronics is that capacitors in parallel have their values added. So when the transistor in my circuit is open the value of capacitance that determines the frequency of the WSG's square wave is increased by 0.01uf. This translates into a lower tone being produced every time the transistor opens and a higher tone every time it closes. The frequency of open / closed cycle is determined by the inverter connected to the base of the new transistor. So instead of your noise maker making just two distinct tones there are now three or more tones to be heard. Below is a sound clip of the mod in action.

The cool thing about this modification is that you can add several of them to the WSG creating a device capable of even greater sonic madness. Just built the above circuit several times using whatever inverters are free on the CD40106 and connect them all to Q1's emitter. Vary the values of the capacitors and see what sort of noises are produced, experiment.

The only change to the WSG circuit I would recommend that you make would be to change the value of C5 to 0.01uf or 0.015uf so the values don't get so high that no audible sound is generated.

You can set it up on solderless breadboard first and connect it to your WSG using patch cords with crocodile clips.

Parts List:

Resistors

130K Ohm 1/4 Watt

10K Ohm 1/4 Watt

1M Ohm Linear Potentiometer

Transistor

2N3904

Capacitor

1uf Ceramic

.01uf Ceramic

.015uf Ceramic

Cigar Box Electric: Sort of

This is a simple cigar box style electric guitar I made last year using the wooden box that comes with the Electro Harmonix Micro Synthesizer as the body. The neck and bridge were just lying around my workshop in Ireland and I had nothing to do that day so after several hours of work I ended up with this weird instrument.

The scale length is shorter than the fret spacing on the neck would like but it still sounds great when played with a slide or prepared or modified with a third bridge. The hollow body gives the guitar a rather unique resonating quality that produces really interesting tones. Below is a sample of some noises I created using this guitar and our latest electronic synth / effect unit, Fotosis No. 004 there is a picture of the equipment setup at the end of the post.

The pickups are good quality single coils that were replacements I bought for my first guitar. It was not being used anymore due to the fact that it had become so modified and broken normal music was impossible to play on it, but it looked and sounded totally cool. I removed the pickups from the old guitar and cut slots into the EH Micro Synth box through which I pushed the pickups and then secured them in place wit four screws.

This instrument was a gift for Connie as was the little Danelectro Honeytone pocket amplifier that we use all the time now as a preamp.

Making Of: The Joys of DIY Instrument Building

These are from a series of 'making of' photos I have taken over the last months. I've accumulated hundreds of photos over the years primarily because this is the magical element of what making things brings to a person, the creation of something from nothing. Secondly, it's just great to see what is inside an electronic object.

The most difficult part (for me) with DIY building has been the wait for parts/materials which, thanks to various local/international outlets online and offline, is still relatively painless. Ironically, we are now waiting for parts.

Our preferred resources for components/parts include:

Bendables Store EBay
Farnell
Arduino
Banzai Effects

Don't forget your local mom & pop shops, they usually have great personal service and are a lifesaver for last minute needs. Enjoy the pics!

-C

How-To: Fotosis No. 000 Schematic...

I've decided to post a schematic for an optical theremin / synth that is a simplified version of our first creation, Fotosis No. 001. Its based around the XR2206 function generator which produces the sound (Sine Wave) and the 40106 chip that I use to trigger the LDR switching function on the XR2206. The controls are simple, three pots and three toggle switches. The pots control volume, sine wave intensity and LDR switching speed and the toggles turn LDR switching on / off (S1), (S2) for high and low pitch setting and (S3) which gives you the capability of redirecting the timing resistor pins on the XR2206 chip to some other form of resistance.

You could build a hybrid sequencer / optical theremin using a micro-controller like the Arduino board with a few opto-couplers switching the timing pins through resistors (4N37's work well) or make a noise maker using the spare Hex Schmitt Triggers on the 40106. There are many possibilities. All of the Capacitors are 1uf ceramic (Farnell part number 110-0420) except C4 which is 0.33uf polyester (Farnell part number 116-6040) all resistors are 1/4 Watt. The LDRs are 1M Ohm in total darkness and the whole circuit runs on 9V dc.

A .PDF of the same schematic can be found here.

Here is a more complicated version we built and sold a few weeks ago, the link includes a video so you can get an idea of what sounds you can expect.

Any questions I will answer to the best of my abilities...