Hearing Pictures – Homebrew Microphone Edition

This coming Wednesday, December 2nd, I'll be giving my new talk, Hearing Pictures at the LA Flash End-Of-Year Party. This will be only the second time I've given this talk -- I first gave it at the FITC Unconference at MAX 2009. Since I was speaking at an unconference (a less formal environment, with very different criteria for acceptability than the normal conference tracks), I used the opportunity to create a brand new talk on a sort of crazy idea that's been nagging me for a few years -- the idea of translating anything into anything.

The idea originated from a 1943 Hermann Hesse novel, The Glass Bead Game (also published under the title, Magister Ludi, after the protagonist). The novel focuses around the life of Magister Ludi, who is a member of a monastic-style order at a time in the future.

The central activity of the order is the Glass Bead Game -- it is their form of meditation. Although it is the central activity of the order, it is rather vaguely defined over the course of the text. Despite the lack of detail, the game has fascinated me since I read the novel. In the game, a glass bead represents an idea -- any idea -- such as an historical event, a work of music, a painting, a philosophical concept, anything. When it's your turn, you must play a bead -- that is, you must play an idea on the game board. But the idea you play (the bead you place) must be related to the idea (bead) placed by the previous player, thus over the course of an entire game creating a thread uniting widely disparate parts of human knowledge and experience. In this way, being a successful player of the game requires an agile intellect with the capacity to relate any idea to a wide variety of other -- seemingly unrelated -- ideas. Playing the game well requires fluency in math, music, language, history, art and science.

Ever since I started working with Flash 11 years ago, I'd always sort of envisioned Flash as a mini-Glass Bead Game. The term isn't really used any more, but when Flash was young, it was considered a multimedia tool. And, Flash took the idea of multimedia to a new level -- that is, despite its drawbacks, Flash has, since version 4, made it ludicrously simple to work with information of many different kinds. Flash supports character animation, motion design, text, audio, video, images, 3D data, live data, interactivity -- Flash basically supports any type of digital information (this is, more or less, literally true with the Flash Player 10 FileReference powers). So, using Flash, we can establish relationships between different types of information (which is what many of the early Flash luminaries did, in one form or another). Hence, my picture of Flash as a mini-Glass Bead Game.

The fact that, especially early on (until Flash 9), the most successful Flashers also tended to be the most eclectic, only strengthened this notion for me. Flash is really the only technology in the world that could give birth to a significant population of designer/developer hybrids (a.k.a., the deselopers), which speaks to the multi-disciplinary nature of the tool and the unique skill-sets that lead to success within Flash.

So, the idea of Flash as a Glass Bead Game kept percolating in my head for years, until I eventually decided to start trying to formalize the notion. The notion of creating a computer program that could translate anything into anything.

But of course, that's an insanely complex endeavor. So, I wanted to find a more focused niche that could serve as a starting point.

Then, Flash 9 came out, with its enhanced sound powers. All of a sudden you started seeing real-time audio analysis in Flash movies -- sound visualizers translating sound into pictures. Now, of course, sound visualizers have been around for a while, but now I could build them myself, using the ActionScript code I already knew. And the thought occurred to me to create a machine that worked in reverse -- translating pictures into music. Still, even with Flash 9's powers, it was a frustrating go. But, when Flash 10 came out, with the SampleDataEvent, I lost all excuses and picked things back up.

Of course, with the amount of time I've been able to spend on the project, it's not even properly called a 'hobby'. And so, I'm now six months into what I consider to be a 40 year endeavor, and I have a few little experiments to show for the effort. Those experiments -- and the thought that went into them -- is what my talk at Wednesday's LA Flash End-Of-Year Party is about.

But, that's not what this post is about.

One key limitation of this entire process is that I'm working with digital information. Now, I'm not complaining -- the fact that all information is digital is what permits us to execute the cross-modal translations with relative ease (i.e., it's easier to translate a picture into music, if both the picture and music are stored as 0s and 1s). However, working in digital is also a bit creatively limiting. When composing music on the computer, I'm composing from audio information already stored on the computer -- more like playing a synthesizer than a piano. Again, that's fine, but I thought it would be fun to start experimenting with analog inputs and outputs (which I can read and control from Flash using my MakingThings Controller Board).

About a month ago, I picked up a copy of Handmade Electronic Music: The Art of Hardware Hacking, which describes, in a series of clearly written chapters, how to go about assembling synthesizers from inexpensive, easily available hardware.

I'm not done with the book yet, but in the early chapters, you learn how to build your own microphones -- a few different types, including contact mics, compressor mics -- even electromagnetic mics (microphones that 'play' the sounds of the electromagnetic fields that surround the microphone).

When I rewrote the Hearing Pictures presentation this past weekend I found a neat way to integrate one of these piezo contact microphones into my talk. A contact microphone is one that can pick up vibrations in a surface, but not from the air. So, you can plug the contact mic into an amplifier, then hold the contact mic up to something that is vibrating and you will hear the vibration through the amp. They're fun to play around with (you can even hear the sound of metal heating up with these mics).

The simple, cheap (<$1.50) contact microphone that I've built relies on a Piezo disc, or piezo sensor (~$0.75). These Piezo sensors rely on the Piezoelectric effect (discovered by Pierre and Marie Curie in 1880, but not industrialized as a sensor until the 1950s) to convert pressure, acceleration, strain or force into an electrical signal.

You need a:

• Piezo disc
• An amp
• An audio jack (that fits your amp)
• A little bit of audio cabling

Audio cables are composed of two wires.

Step 1) Take one wire and solder it to the outer plate of the piezo disc, and solder the other end to one hookup in the audio jack.

Step 2) Then take the other wire and solder it to the inner plate of the piezo disc, and then solder the other end to the 2nd hookup in the audio jack.

Step 3) Plug the jack into the amp, and start rubbing your piezo disc against things to see how they sound

That's it! You don't even need a battery to power this mic. As you'll quickly see, you can not pick up any vibrations from the air -- so it's totally unusable as a traditional mic (read the chapter on building a condenser mic if you're interested in that). But, if you place it on the end of a styrofoam cup, and then speak into the cup, you have a neat Halloween microphone!

If you're interested to see how I integrated this contact mic into my talk, well then, all I can say is, show up on Wednesday. It's free, and it'll be a really cool and interesting talk. (Oh, and there's free beer -- did I mention that?).

Share and enjoy!

-r