What I Bent Over My Summer Vacation
circuit-bent synthesizer array
If you’ve followed this blog for a while, you’ll remember that I went kind of gonzo about circuit-bending this past Spring. After about half a dozen posts, I realized that not many of my readers could relate to my interest in rewiring children’s electronic toys. So, I dumbed down my posts to encourage the idiots among you to keep reading, but that doesn’t mean that I’ve lost interest in making music with creatively modified, cast-off electronic toys.
Quite the contrary, over the summer I created a number of circuit-bent instruments from electronic toys I found in our local thrift stores. While not every toy I bent, worked out as well as I hoped, enough of them survived surgery that I now have an array of amusing looking, capable, and unique sounding of synthesizers at my disposal. 
While most electronic toys designed for children are nearly bullet-proof, they all share one weakness. One substance has probably stopped more electronic toys from ever working again than any other. This substance corrupts them from the inside, like kryptonite does to Superman. That substance is pee.
According to my extensive research, fully half of all electronic toys found in thrift stores, contain pee. Sure, they’ve cleaned the toy off. You can’t see any pee on it, but set it down in front of your dog or cat. They’ll let you know. Of course, when you open the toy, you’ll find it. Usually, it leaks through the keyboard, or the buttons, and directly onto the little membrane switches beneath them. This causes keys not to play, and functions not to work. Sometimes you can fix these problems with a thorough cleaning, sometimes not.
The worst case pee scenario happens when pee gets all over the main circuit board. Such was the case with my beloved Bratz drum bra. The cups of the bra channeled cat pee directly onto the main circuit board where it dried to an oily, foul smelling film and proceeded to corrode everything. Despite that, the device continued to work, at least long enough for me to add a pitch bend control and a line out, which actually made it into a great sounding instrument. Since then, however, it works only intermittently.
Now that the sun has disappeared behind the hillside, leaving my photovoltaic panels unkissed by sunlight until next March, and thus bringing my summer soldering season to an end, I’ve begun exploring the musical potential I’ve unleashed in these newly altered devices. Allow me to introduce you to a couple of them:
Introducing; My Circuit-Bent Casio ML1
This amazing little instrument pleases me greatly. Stock, it actually makes some pretty good sounds, including a decent imitation of a piano, and it still works as originally intended. However I’ve added a matrix of touch sensors which allow me to directly stimulate the electronic “brain” of the ML1, releasing its previously untapped potential for composing original music of apparently infinite variety. I enjoy collaborating with the ML1, a relatively young composer, and very much a product of the digital age. As a composer, the ML1 speaks to the age in which we live. 
I titled our first collaboration 13 Minutes at the End of Time. The modified ML1 generated every note, phrase, rhythm and noise heard in this piece. My input came only in the form of touching the sensors that I added. Touching any two of these sensors at the same time, creates a new connection within the ML1′s electronic “brain”, causing it to “think outside the box” with surprising originality.
Like many young composers, the modified ML1 favors quick tempos and complex poly-rhythms, but it balances them with subtle textures and sustained notes that float serenely over the fray. I think this piece reflects the relentless sensory overload and chaos of our wired lifestyle. At 13 minutes, it runs a little longer than the typical modern attention span, but some of us still know how to listen. 13 Minutes at the End of Time also provides the perfect ambiance to induce stress into any situation.
Pretty in Pink
I found this pink “girly” toy keyboard at a thrift store around here. Although it had a few splashes of pee inside it, it cleaned up easily with no damage to the electronics. This toy says “Starring Me” on the front, but it looks identical to this “Barbie” toy keyboard bent by Bogus Noise UK, and immortalized in this video. I presume I have the generic version of the same toy.
I took a different approach to this toy than did the braceletted British bender who bent the bejeezus out of that Barbie brand Bontempi. I started with the ubiquitous pitch-bend mod. This is one of the easiest, and most universal bends that you can make on an electronic toy, especially the cheap ones.
Almost all of theses little noise-making electronic toys, use a single resistor to set the speed of the central processor. If you change the resistance of that resistor, you can make the whole machine operate faster or slower, which in turn, raises or lowers the pitch of all the noises it makes. You will usually find this resistor located right next to the black blob in the center of the circuit board, often labeled “R1”.
If you touch this resistor at both ends, the toy will usually go up or down in pitch dramatically, or stop working all together. If you replace that resistor with a potentiometer, you can use that potentiometer to sweep the pitch of the sounds up or down. This opens up a lot of new potential sounds for you to exploit.
In this pink girly keyboard, I used one of the purple ornamental flowers as the knob to adjust the pitch. The three switches on the lower left, allow me to switch even more resistance into the circuit, which allows me to play the keyboard in four distinct registers, with the pitch-bend knob active in all of them. This four-speed pitch-bend mod extends the toys range by nearly an octave above, and several octaves below, it’s original voice.
I made one other major modification to the sound of this pink girly keyboard. I added a passive ring modulator. A passive ring modulator adds a very weird kind of distortion, and it allows you to use another signal to change the harmonic profile of that distortion in very strange ways. Q Reed Ghazala shared this schematic of a passive ring modulator on his Anti-Theory website.
It looked pretty simple to me, consisting of two transformers and four diodes. Even I could handle that. For the secondary, or “Y” signal, (that modifies the original or “X” signal) I built an analog square-wave oscillator from an 8-pin “555” chip, relying on the instructions I found in the Crème DeMentia “Bending Buddy” comic book. Everyone interested in circuit-bending should check out the Crème Dementia kits and comics.
Both circuits fit easily on a 2” square piece of circuit-board, and inside the toy. The “Y” oscillator has an independent on/off switch with an indicator LED, and a pitch control knob. Another knob blends the “Y” oscillator with the “X” signal. You can see the switch and indicator light between the two purple flowers on the upper right, and the control knobs located to the immediate right of the keyboard.
I displaced one of the ornamental purple flowers to make space for a quarter inch phone jack that serves as a line-level output, but I re-purposed the flower as the pitch-control knob. I added three tiny LEDs to the handle, to make my new instrument extra pretty, an amber one in the center, flanked by two red ones, because I had them lying around. The red ones came out of a small power inverter that burned out, and the amber one came from a disposable led tea light, with a dead battery.
How does it sound? Th passive ring modulator give this toy a very biting and aggressive sound, reminiscent of a an old Farfisa organ through a fuzz box. The analog oscillator feeding the “Y” oscillator dramatically alters the harmonic character of the sound in real time, with a twist of a knob, not unlike an analog synthesizer, and imparts an authentically analog Theremin-like sound on it’s own.
I composed this rather abstract, obtuse, but somehow endearing piece entirely with the newly modified pink girly toy keyboard. It reminds me of some of the electronic music popular in sci-fi movies of the sixties.
As you can see my enthusiasm for circuit-bending has not waned. I hope at least a few of you enjoyed this look at a couple of my new instruments. I built these instruments to force me to think about music in different ways, and I hope this approach will lead to some interesting and hopefully compelling music in the coming months. Stay tuned.
