electricity

Pretty bird by kelly heaton

A sculptural bird circuit that sings “pretty bird” when the ambient light conditions are favorable. The exterior is folded Mylar and the interior is an analog electronic chirp generator soldered freeform. This part is part of a larger work in progress.

Above: images of the freeform chirping circuit (stabilized to Mylar using glue) prior to insertion into the bird’s body.

electronic sculpture by kelly heaton

I've built artistic electronics for years, but when Hackaday’s Circuit Sculpture Contest came along, I took it as an opportunity to build a purely sculptural circuit. I was intrigued by the challenge to ditch all forms of 2D and go completely freeform. (Incidentally, non-traditional planes for embedding electronics, like paper and canvas, are a great way to make electrified paintings. Totally freeform circuitry is an eccentric labor of love... but then again, so are all forms of art.) 

Here's what I ended up making for the contest, a mama bird with her baby in a nest:

Mama Bird with Baby, 2018. Analog electronics and wooden branch

Mama Bird with Baby, 2018. Analog electronics and wooden branch

Disclaimer: the branch is wood, but I had to put the nest on something... and I preferred the contrast of a natural material over a piece of wire. I could have put them on a big electrical transformer, like some birds do for reasons I can't understand, but I didn't have a transformer handy. 

However, I do own loads of surplus resistors in different colors, collected over the years, which I use to create mosaic effects in my art. If you want a similar aesthetic, don't buy new resistors -- get some old surplus components and/or unsorted resistors for cheap. You can always measure them (and combine them in series or parallel) if you want to use them in a functional circuit.

The shape of the mama bird is made entirely out of resistors and she's hollow inside, which is where I carefully, painstakingly installed her freeform singing circuit. The baby bird is nestled in a nest of wires --not altogether different from the real thing-- and the light-colored object in the nest is an 8 ohm speaker wrapped in heat-shrink tubing (to mechanically dampen the sound). Both birds have a photoresistor that enables you to interactively affect their chirping. Here's a video showing the pair making their avian sounds:

I used a small segmented display to visualize the baby bird's yapping beak. I love how it "shuts up" when you wave your hand in front of the photoresistor. I have uploaded my baby bird schematic to my project page on Hackaday.io so you can check out how I achieved this effect using discrete hardware components. 

The mama bird's form was time-consuming and required two types of jig. First, and most importantly, the overall shape of her body: it's very hard to create a complex shape from hundreds or thousands of resistors without some guidance, especially because wires are prone to deform and collapse inward on a volume. After some experimentation, I discovered that regular modeling clay is a great substrate around which to form and solder electronics. Don't use plasticine clay - it will melt if you solder near it.

Below are a series of photographs showing how I made the shape of the mama bird:

bird_process_clay_form.jpg

First, I modeled her rough form in clay. The volumetric proportions must be accurate, but the details don't matter -- you'll use needle nose pliers to shape the final touches when your wire sculpture is nearly complete. Don't cut corners on the basic volumetric form or else your fundamental proportions will be wrong, and that's hard to fix.

Next, I arranged resistors on the surface of the clay form and soldered them with the aid of a jig (more details on the second jig in a moment). Press the resistors into the clay to hold them steady. Natural clay is a great substrate onto which to solder, assuming it's not too wet and mushy. Don't worry about getting your resistors dirty, because you can wash the sculpture gently before you add active components (just leave time to dry if you plan to use the sculptural resistors as part of a functional circuit).

bird_process_belly.jpg

I played around with different patterns to define regions with texture as well as color. 

As you go along, leave yourself an opening to remove the "resistor shell" from the clay form. I left a seam along one side, underneath the bird's wing, where it would not be visible in the final piece. I also used this seam to insert the functional electronics inside.

Now for the second jig: if you try to solder together a bunch of resistors (or whatever) lying freely on your bench, they are prone to move. That's another great application of modeling clay: see the small blob sitting on my bench to the right of the bird? I used it repeatedly to hold resistors in a pattern so that I could shape and solder them. Clay is a really great way to hold parts in place. Mash it into whatever form you need.

bird_process_jig.jpg

So that's how I made the form of the mama bird. It took me several days. Each night I would remove the clay form from the wireframe and store it in a sealed plastic bag (so it wouldn't dry out). If you keep the clay damp, you can reuse it indefinitely.

Below is a photo after I finished sculpting the mama bird on the clay jig and opened her along the seam to insert the functional electronics. (Her circuit was based on a bicore design by Wilf Rigter).

bird_stuffing.jpg

Unfortunately, it's hard to see what's going on with so much complexity... but if you look along the underside of the wing you can see a horizontal opening that runs from the base of her belly to the tip of her beak. I left several longer, unsoldered leads along both edges of the seam so I could twist them shut without soldering (in the inevitable case that she needs to be opened for repair).

An interesting side note on making a complex sculpture out of linear electronic components: remember Thevenin's equivalent? Find any two points on the resistor network, measure them with your multimeter, and voila -- you have a resistor of known value at your disposal. I didn't end up tapping into her body for resistance, but I certainly could have done this (and probably will on future projects). I did insert the photoresistor into her head though, like the third eye that bird's reportedly use for long-range navigation. You can see a detail of that below.

bird_brain.jpg

Thanks for reading! Ciao for now

Mexican Birds by kelly heaton

I've been remiss in my project documentation since returning from Mexico's Yucatan peninsula (and end-of-year distractions).

This post revisits the bird studies that I built during my time at Tortuga Escondida near Akumal, Mexico. For my residency, I took a miniature version of my electronics workbench with me for five weeks of study in the jungle, where hacking supplies are not only unavailable but subject to failure due to fluctuating voltages, high humidity, sporadic connectivity, jungle wildlife, and mischievous Mayan spirits called "Aluxes." Electricity really is different in the rural Yucatan than most modernized parts of the United States. It was a fascinating albeit frustrating experience to build delicate circuits in such an uncertain environment, especially after my oscilloscope died from any number of mysterious causes. I'm not complaining, though -- it was one of the most memorable experiences of my life and gave me new appreciation for the complex relationships between electricity, nature, and culture. When I left, I donated my electronic supplies to the Akumal community center, hopefully inspiring some intrepid hackers in the pueblo. I plan to return.

Back to my birds. I brought with me several printed schematics and data sheets as a point of departure, and these proved invaluable given my lack of a printer onsite (and unreliable Internet access). The schematics were all different strategies to produce simple, bird-like chirping sounds for novelty (like a doorbell that sounds like a squawking parrot). Here's an abbreviated list of the circuits that I tried during my time down there:

Wilf's Bird Sound Generator. This BEAM circuit is an ingenious use of a hex inverter chip with effects that are fun to play with due to feedback. I built several different bird sounds with this as the basis, including my recent "singing mama" bird.

Parrot Sound Generator. There are multiple circuits included on this page, but the parrot sound generator was the only one that really intrigued me. It uses a center-tapped transformer as well as an inductor (or one side of a second transformer) to create a chirping sound thanks to some cool physics. All circuits are thanks to physics, but here it's really obvious because you're basically listening to electricity flow through a coil. The easiest component to use for the non-center tapped coil is an inductor. Out of curiosity, I tested an old transformer that I found in Mexico and the results were intriguing. As you would imagine, it sounds "big" as compared with a smaller inductor.

Bird chirp sound generator. This is the same principle as the previous parrot sound generator, but with a slightly different configuration. If you're curious about how the transformer and transistor work together to create sound, build both circuits -- it helps to have more than one view on the same principle. Here's video of this circuit in a piece I made years ago called "Restless Bird Chatters, Still Bird" (2018):

Two canaries singing in a cage. This is a more complicated circuit, but you do get two birds for your effort (albeit similar sounding). Is it worth it? The jury is still out for me. I used it to create my piece "Bird Study #1 (Tortuga Escondida)" (2018) but to be fair, the circuit got messed up when I soldered it (with my crappy soldering iron--never use a crappy soldering iron when you have a better option). So the following video is not a good demonstration of the circuit’s proper effect. In fact, it's barely recognizable due to design changes and errors, but it's the basis for this piece: 

Bird Study #1 (Tortuga Escondida), 2018.  Analog electronics and watercolor on paper with custom wood frame

Bird Study #1 (Tortuga Escondida), 2018. Analog electronics and watercolor on paper with custom wood frame

I like the painting. Incidentally, people often ask me whether my nature studies are associated with particular species of animals (in the above case, a Dot-winged Antwren and Hooded Oriole). Of course I want my circuits to sound exactly like a species, but this almost never happens. I start with a sound and tweak it until I generate audio that is as close as possible to my subject, often chancing upon a circuit that sounds entirely different than what I originally intended, and then I paint (or sculpt) whatever noise-making creature seems most appropriate to my creative process. I'm principally an artist, not a scientist. Is that a cop out for my inadequate engineering skills? Um, yes. But I would never build any electronic artworks if I held myself to a triple standard of artistic, electronic, and biological accuracy. I try to achieve this trifecta with every piece, but my works often fail to recreate nature faithfully. I don't consider this an artistic failure, though, because the effort to mimic nature is really hard. That's in large part what my work intentionally reveals: the difficulty to mimic lifeforms using manmade media --a timely lesson for our civilization as we separate from nature and try to build our own reality. (I regularly think about Icarus trying to fly to the sun.)

I conclude this entry with the second work that I created while in Mexico, which is a diptych.

The sounds you hear in my Mexican orioles piece are some combination of the circuits that I have described in this post (with tweaks but no significant departures). What I really wanted to capture is the crazy, chaotic chattering of birds that I often heard in the jungle surrounding my residence center. Birds can be really loud in Quintana Roo, like a raucous family at a gathering in which everyone talks all at once and increases their volume trying to be heard. I captured only a fraction of the real experience, which is a great excuse to return and keep trying.

Sitting here in Virginia, on a January day with a cold winter landscape, I definitely want to return to the incredibly energetic, diverse, and otherworldly creatures of Mexico.

Mexican Orioles, 2018.  Diptych of analog electronics and watercolor on paper with custom wood frames.

Mexican Orioles, 2018. Diptych of analog electronics and watercolor on paper with custom wood frames.

Tortuga Escondida Fellowship || Akumal, Mexico by kelly heaton

I’m back from a transformative five weeks in the Yucatán peninsula. This blog entry has been difficult for me to write because I’ve got so much material and it’s not easy to articulate. I will try to present my impressions of living in Mexico, the quirks of electrical engineering in a tropical jungle, my work with the people of Akumal pueblo, and how this experience has changed my life —at least, in a preliminary view.

The story and accomplishments that I describe were thanks to many supporters: the staff of Tortuga Escondida for inviting me to be a resident; GoFundMe donors and Creative Capital for making my work financially possible; the Akumal Arts Festival for supplying me with paint, a blank wall, and so much more; the Centro Comunitario de Akumal Pueblo for accepting my electronics donation and empowering the community to learn new skills; and to my new friends in Mexico who received me with open arms and showed me a fluid world of magic. From the bottom of my heart, thank you to everyone who made this giant, messy “ball of happiness” possible. You have given me a life-changing experience that continues to unfold with powerful momentum.

Jaguar spirit holding the fire during a Mayan cacao ceremony, November 2018. Yucatán Mayans say that there are as many portals in the universe as there are spots on a jaguar.

Jaguar spirit holding the fire during a Mayan cacao ceremony, November 2018. Yucatán Mayans say that there are as many portals in the universe as there are spots on a jaguar.

My original intention for traveling to Mexico was to study the sounds of nature in a tropical jungle, feel the local energy, and build electrified works of art based on my experience. I also wanted to teach local residents about electricity and circuit design, hopefully inspiring some new “makers” in the small town of Akumal, Mexico, where tourism is the predominant industry and other educational opportunities are sparse. I am pleased to report that I achieved these goals and much more, but my path was not straightforward.

Tortuga Escondida residency center is located in a tropical jungle several pot-hole-dirt-road kilometers outside of Akumal pueblo. If not for the occasional outing, you would never know that Akumal is nearby, much less the overdeveloped Mayan Riveria coastline. Isolation in the jungle gave me plenty of natural inspiration and afforded me headspace to tackle a new challenge: circuits that sing like birds. I created three new works of electronic art thanks to and despite the wonderfully weird circumstances down there. Electrical engineering in a tropical jungle is challenging for many reasons, some of which I predicted (wildlife, limited supplies, high humidity) and some surprises (power fluctuations, mischievous house spirits, no package delivery, unreliable connectivity). I forgot a few supplies and inadvertently damaged others that were thankfully replenished by friends of friends visiting from the States —bless them, because it can take weeks or months via a “mule” to acquire something that isn’t locally available. Still, my oscilloscope abruptly died at the end of week two, even though it was unplugged and stored in a sheltered location with air conditioning. Locals claimed it was the work of an "Alux," pronounced "Aloosh", a Mayan nature spirit similar to an elf or house goblin. Apparently, the Alux that lives on the grounds of Tortuga Escondida likes to sabotage electronic devices and has killed so many hot water heaters that they’ve given up on replacements. They’ve even consulted an Alux removal specialist (a real vocation in this part of the world). Anyway, I managed without an oscilloscope and hot showers, and below are images of the works that I produced with my make-shift electronics bench at Tortuga Escondida.

Above: three electrified watercolor studies of birds in the Yucatán Peninsula. Tortuga Escondida’s caretaker generously built three wooden frames to protect my work (one frame not shown). Near Akumal, Mexico, 2018

Thanks to supporters of my GoFundMe project, “Hacking Nature’s Musicians | Mexico,” I donated the electronics bench that I used to create these bird studies to the Akumal Community Center, where several high school students and professors have been appointed as “electrical engineering champions.” Until now, there hasn’t been any sort of electronics hacking equipment in Akumal for students to learn about circuit design and safely experiment with electricity. Local educators determined that the pueblo’s community center was the best location for an electronics bench because the school cycles through three different age groups in a day, and it’s a pretty chaotic environment.

Fortunately, another electronic artist (Jackie Neon) came to town for the Akumal Arts Festival, and she helped me to lay a crucial foundation of interest and understanding. Jackie hosted several all-age, all-skill-level workshops called Sense Circuits, in which participants learned how to connect an LED or motor to a battery using conductive (and resistive) thread. I was really impressed by her workshop design because it’s not easy to teach total beginners about electronics without the risk of breaking components. Based on community response to Jackie’s Sense Circuit workshops, I was able to identify members of the community who have the interest and discipline to go further with electrical engineering. I hosted a two-hour workshop in mediocre Spanish to explain the equipment that I donated to the community. I offered tips for independent study, including how to search for schematics on the Internet, and the importance of studying data sheets. One participant was so enthusiastic in his desire to learn electrical engineering that he bamboozled me with hard questions. I was thrilled to know that this equipment will be appreciated and used.

Besides my interactions with Jackie Neon and her Sense Circuits workshops, I was only vaguely aware that the inaugural Akumal Arts Festival would happen during my residency because painting a mural wasn’t part of my fellowship proposal. So much for plans. About the time that my oscilloscope died, after two intense weeks of studying birds and building circuits in the shady jungle (like a pasty, hunchbacked golem), a friend drove me to Akumal to see the first mural in progress. It was a sunny day and the athletic, tan, happy street artist was covered in sweat, bright colors, and grime. The impression hit me like a ton of bricks: this artist is having way more fun than I am. Painting a street mural seemed like the perfect way to balance out my endless hours of cerebral circuit bending. Plus, what an opportunity for me to make a difference in the landscape of Akumal pueblo —a dirty, unattractive town at the time of my arrival in mid-October. And so it happened: I befriended an Akumal resident who offered to assist me, selected a wall (actually two walls that join in a corner), quickly sketched a design, ordered house paint, and put myself to the task of creating my first-ever work of street art, “Dos Dioses de la Electricidad.” The next five days were filthy and exhausting to an extreme, especially given my lack of physical fitness and reconstructive hip surgery two months prior, and painting on a ladder in tropical heat is not trivial. But —wow— what an incredible experience to work in the streets, meet curious strangers, talk to the police, witness someone be put in jail, hear a noisy Mexican town, and explain the meaning of my art in a foreign language. More than anything, truly beyond what I can put into words, I was blown away by the utter transformation that took place in Akumal. More than 80 artists came from all over the world to paint the town, and the energy rose in a palpable crescendo. Cinderblock buildings, an empty square, and trash-filled streets were transformed into an outdoor art exhibition with clean sidewalks, a new playground, and the beginnings of a proper Zócalo. At the closing ceremony —scented with sacred copal, high on sugary churros, and drunk on a feeling of civic love— we were all laughing and crying and gasping in disbelief at our good fortune to be part of an experience so uncommonly beautiful. I am convinced of the power of art to change lives because I’ve seen it happen beyond a shadow of a doubt.

Above, left to right: corner of the Akumal Delegacion Building as I first found it; a concrete pillar painted by my friend and helper, Patricia Delfin (Mayan long calendar date format for “November 9, 2018”); a dirty and triumphant me at the conclusion of the mural.

As far as I can tell, Mexico is a place where things don’t usually go according to plan. “Expect the unexpected” should be the country’s motto —and I say this with the greatest admiration— for while Mexico’s surprises were initially frightening or aggravating to me, I came to accept the steady drip of unexpected events as medicine for my generalized anxiety disorder —more therapeutic than any treatment I’ve encountered in my decades-long journey through the western medical system. Living in Mexico forced me to find freedom and humor in my loss of control, an enduring lesson that far outweighs whatever discomfort I may have experienced in the short-term. I’m not saying that it’s easy for me to flow with my environment. I’m saying that resisting a strong current feels worse, and flowing offers the added benefit of inner peace. Apparently some visitors won’t let go of their desire for control and become chronically pissed off (I met several expats in this toxic state), but we won’t go there except to say that hating reality is futile. One must accept reality or work for change. Where struggle is concerned, I like the wisdom that Don Juan imparts to Carlos Castenda in “A Separate Reality,”

The spirit of a warrior is not geared to indulging and complaining, nor is it geared to winning or losing. The spirit of a warrior is geared only to struggle, and every struggle is a warrior’s last battle on earth. Thus the outcome matters very little to him. In his last battle on earth a warrior lets his spirit flow free and clear. And as he wages his battle, knowing that his intent is impeccable, a warrior laughs and laughs.

To be sure, Mexico is not an easy place to live and work and sometimes it’s downright harsh —hardly a laughing matter. But in my recent experience, most Mexican nuisances were harmless: enormous tarantulas crawling peacefully through in my dormitory in the evening, to disappear by next morning; a voracious combination of humidity and voltage spikes that ate away my soldering iron, leaving me to weld with a tip as blunt as my index finger; and the giant pile of sand in front of the police station, with no obvious owner or purpose, which tripped me repeatedly during the week that I painted my Akumal mural (despite polite requests for removal), and was suddenly shoveled away by an incarcerated drunk the day after I finished work. And then there was the negative energy oozing through the wall opposite the jail cell which caused half of my mural to peel until I performed an impromptu healing ceremony that stopped the peeling but gave me a roaring head cold. (I followed the advice of a local healer and tried to expel my flu with a temezcal ceremony, but suffered a panic attack and was compelled to crawl over the bodies of multiple acquaintances on my premature exit from the sweat lodge.) To ensure that I wouldn’t lose my temper over daily challenges, I was fortified each night with cold showers, scorpions in my sink, and friendly but dutiful guard dogs who barked at 3am, or 5am, and maybe both times and then some. Barking dogs were mitigated with ear plugs, but waking to thousands of ants migrating across my room, bed, and body —that required a new level of personal zen.

Some triggers of fear in Mexico (above left to right): large hand-sized tarantula near the entrance to Tortuga Escondida; the Akumal jail cell; an entrance to Xibalba; the tree of life deep inside Balankanche cave near Chichen Itza

Surprises are not always hard to stomach. Oftentimes, Mexico is downright magical in the happiest sense of the word. I achieved fascinating results in my jungle-improvised electronics studio, and I even witnessed multiple species of birds singing in response to my chirping circuits. I gave my first electronics class in Spanish and had the distinct impression that I changed a man’s life. I made several life-long friends in less time than I spent maintaining distant, unsatisfying contact through social media. I managed to paint a large portion of my first street mural using a cheap roller that fell into the dirt repeatedly (i.e., once or twice a minute). I witnessed strangers open their hearts and give freely in a multi-cultural exchange that overcame grudges, judgement, and hierarchy. I used a paper map to navigate poetic roads across remote areas of the Yucatán peninsula. I met people who unabashedly believe in the existence of spirits, and I participated in five Mayan ceremonies. I climbed ancient pyramids and wondered why great civilizations were abandoned at least five hundred years before the Spanish arrived. I saw Morpho butterflies, Motmot birds, Tucans, Chacalacas, Flamingos, Howler monkeys, and giant Iguanas. I swam with sea turtles, heard strange owls, watched millions of bats fly in a vortex, and felt the presence of a jaguar. I stayed up all night in the jungle, sang a mixture of Mayan prayers, Christmas carols, and southern spirituals, confronted my fears in multiple sweat lodges, and descended into Xibalba four times. I left with the distinct impression that hardship is not something to be avoided, but embraced as a practice of spiritual growth, perhaps as the only way to cultivate openness to the truly good stuff in life —the stuff that money and convenience simply cannot buy.

Below are a few of my photographic impressions, although most of the magic I witnessed could not be easily captured. I will have to create works of art for that which words and cameras could not record.

Thank you again to everyone who made this amazing experience possible! Yum bo’otik.

Dos dioses de la electricidad by kelly heaton

“Dos Dioses de la Electricidad,” 2018. Mural in Akumal, Mexico as part of the 2018 Akumal Arts Festival and Residency.

This weekend marks the inaugural Akumal Arts Festival (11/9-11) and the energy here is just incredible. 80+ muralists have traveled from all over the world to paint the pueblo. With such excitement all around, there was no way that I could hide in my electronics studio… and so I have joined the merriment and painted my very first outdoor mural (!) on Akumal’s Delegacion building, aka the police station. I witnessed two people be temporarily incarcerated while I was painting (for public drunkenness)… washing my brushes next to them was a socially awkward and lifetime memory for sure.

My mural spans two walls joined by a corner, so I painted the two gods of electricity in dialogue: K’awiil, the Mayan God of lightning and a modern God of electricity. In front of the murals there is a concrete pillar for electricity, so we are painting the date there in Mayan Long Calendar format (Nov 9 2018). A colleague was kind enough to translate my first name into Mayan, so I signed the K’awiil side with my hieroglyphic “Ix-Ke-li-i,” where the “Ix” is pronounced “ish” and indicates that I am female. Note that the blue and green border beneath the Gods is perforated with cenotes, the holes in the earth that grant access to the world's largest river (entirely underground and spanning hundreds of miles across the Yucatan peninsula).

The pile of sand in front of my mural has been there since the very beginning — I didn’t put it there and while many promises of removal were made, it remains. I think it was placed there to be my petty tyrant for the duration of mural painting and I’ve come to quite like it in a weird sort of way. Either that, or painting for days next to a jail cell in the Mexican heat has made me a little bit crazy ;-)

More bird experiments by kelly heaton

bench_mexico_end_of_october.jpg

I continue to explore circuits for bird song creation. I'm working my way through various schematics found on the Internet, testing them to hear how different parts and configurations sound. So far, most of the bird circuits I've built fall into the "chirping canary" or "depressive parrot" categories. Just prior to this log, I discovered another schematic to try -- and it's accompanied by a really helpful video by Mario Burriel Valencia aka @DJ Mystic  https://youtu.be/W69VaPoPoVo

@DJ Mystic confirms what I have long suspected -- it's not only the shape of a waveform (sine, square, triangle, sawtooth, etc), or the component type (resistor, capacitor, transistor, etc), but the *specific make* of a component that can affect pitch, timbre, and loudness. This is especially true for transistors, and I have also seen variation in capacitors. ...Yes... I have read blogs by audiophiles discussing the pros and cons of specific parts for hi-fi equipment, but I didn't fully appreciate the importance of component specificity in low-cost sound generation. For some reason I assumed that since I work with cheap parts, the make wasn't that important. For example, I have thus-far thrown 2N3904 transistors at every problem they will solve. Now I realize the power of expanding my palette. Fortunately, I've got a friend coming down from the US and she's willing to bring a bag of electronics with her... so stay tuned for that excitement.

As for progress in the past few days, I bit the bullet and breadboarded a circuit with op amps. My attitude may seem weird considering that most synthesizer enthusiasts live and breathe op amps... but the dual power supply annoys me (and I've never gotten interesting effects with single supply op amps). Fortunately, some years ago, Bernie Hutchins gave me a useful schematic to convert voltage from a DC supply into a negative voltage of almost (not quite) the same magnitude. So if you have a 12 volt supply, you can produce negative 9-10 volts using a 555 timer and a handful of components. Please see my project files on Hackaday.io for this handy "Negative supply" circuit, or read about it on Electronotes.

The bird circuit that I built with op amps is described as "two canaries singing in a cage." You can find the schematic here: http://circuitos-de-electronica.blogspot.com/2007/10/canary-sound-simulator.html

I substituted a bunch of LM741s for the LM324s because I don't like building in tight quarters. You can see the resulting circuit in this video, where the "two canaries" are in the breadboard in the foreground (a previously built "transformer canary" is in the background):

I added some photocell resistors plus a few wires that you'll see me moving around (poor man's patch synth) to get variation in the circuit's behavior. It's pretty interesting, but maybe not worth the effort because there's a fair amount of complexity for sound effects that can be achieved with fewer parts. Still, I might make one of my electronic painting / sound studies with it because I like the aesthetic of crazy-complicated circuits.

Last but not least, here's a short video of a different bird circuit (the transformer one discussed in my previous log and shown in the background of the "two canary" video). I tested various capacitors and it's pretty cool the realistic bird sounds that you can achieve with such a simple component swap.

Still lots of work to be done.

New bird in town by kelly heaton

I've temporarily relocated the physical form of Hacking Nature's Musicians to the other-worldly environment of Tortuga Escondida (near Akumal, Mexico) for a one-month fellowship on los musicos de la selva. Thankfully, my supplies made it through airport security and there's air conditioning to protect my electronic equipment against jungle humidity. Here's a photo of my bench showing a view of the jungle canopy and stairs to a roof deck with an amazing panorama over the electrically-charged ecosystem. (Giant scorpions occasionally grace my window screens but I have spared you that visual discomfort.)

My electronics bench at Tortuga Escondida near Akumal, Mexico. October, 2018

A few observations before I jump into the main content of this log: (1) Tortuga Escondida seriously resembles a research facility from the TV series Lost, so if I disappear you know what happened to me; and (2) the insects here are at least twice the size of their Virginian counterparts. Check out this insane Katydid!

Amazing giant Katydid in the jungle around Tortuga Escondida (greater Akumal, Mexico). October, 2018

Amazing as the insects are, I'm not studying musical bugs because what's most remarkable to me --coming here from Virginia-- are the myriad species of birds. I've decided to see what I can do with the analog electrical engineering of bird song. 

As a starting point, I built a version of the classic, "chirping canary" used in kitschy artificial nature scenes. Check out my files on Hackaday.io for an annotated version of this schematic, which is based on audio transformer oscillation. Basically, the surge in DC power that happens when you first turn the circuit on is capacitively coupled across the transformer and continues to fluctuate thanks to a transistor switch. If you change (or remove) certain capacitor values, the circuit stops oscillating and makes an unpleasant tone that can be very loud due to the current gain across the transformer.

I've made a first informal video showing how the sound changes when different parts of the circuit are modified (apologies in advanced for some unpleasant beeps - don't wear headphones).

Next, I built a few astable multivibrators and connected them to various aspects of the sound-generating circuit in order to make the chirp sound more like a bird song. Some of my tests are documented in a second video that you can watch on Vimeo.

Watch the green LEDs (and follow the white wires) to get a sense for what the astable multivibrators are doing. 

Birds are very clever singer-songwriters, so it's going to take a lot more work on tempo and pitch variation to get interesting songs. I plan to try numerous strategies to generate voice quality because I want to build a jungle of different bird circuits ranging from sparrows to whippoorwills to parrots to owls to a Resplendent Quetzal, relative of the legendary Mayan Plumed Serpent. If you have suggestions for circuits to try, I would be grateful.

So... not only do my bird electronics need work, I could use a new "avian speaker" design. It seems that piezo buzzers are better suited to insects, while 8 ohm speakers have higher bird fidelity. Initially, this observation puzzled me (and I'm still not clear) but I got some useful clues from the ingenious musician, Nicolas Bras. It's material physics: the thin, metal vibrations of a piezo disk have more in common with the chitin instrumentation of an invertebrate than the fleshy air bladder and vocal chords of a squawking bird. Some insects do force air through a membrane, like living kazoos, but crickets rely heavily on the idiophonic effects of leg or wing rubbing. The sound made by an idiophone is quite different than that of an aerophone or membranophone, like hitting a cymbal versus blowing through a reed, the latter of which happens when a bird forces air through its vocal cords. I searched the web for homemade instruments that behave like an aerophone with a membrane and found this cool "membranophone" video by tachionics. 

As I did with my "insect-like" piezo, I'd like to build an electronically actuated speaker that has material properties more in common with a bird. I've got various 8 ohm speakers that are working for now, but I suspect that there's a better design to be made -- or at least some cool insights to discover in the process of trying. Again, your suggestions are greatly appreciated!

Stay tuned.

This tarantula was found dead, but I couldn’t resist photographing its exquisite corpse. Impressive creature!