My final for my Sustainable Energy is the SolaSystem, which was co-created with Justin Downs & Florica Vlad. It’s a solar powered amplifier to be used for guitars, mp3 players, computers, or whatever you want. Right now, it’s at 14watts power at 16v, give or take 1amp, but we’re gonna upgrade the amplifier to a class D amp that’s more efficient and powerful. The panel outputs more volts and amperage than was listed, so we installed a voltage regulator to control how much power we’re feeding the amp. The sound still gets a little fuzzy at points. The current amp just needs to go.

Here’s some videos of the SolaSystem in action.

RAD!

My ITP thesis, the EM Brace, is up and running. The EM Brace is a wearable device for physically engaging with ambient electromagnetic frequencies emitted by computers and other electronics. It does so by turning these frequencies into sounds that are sent into a “bass-shaker” speaker in the back of the device. Metallic arms reaching around the wearer help distribute the vibrations coming from the speaker.

Here are some testing videos and photos of fabrication and “guts” (preamp circuit, amp circuit, speaker). For specific component parts, check out the previous “thesis” entries.

I’m no great illustrator, but here’s a rough sketch of the device, scaling mistakes and all. From this perspective you would be facing the back of the wearer and the extended “arms” would be wrapped around the persons stomach.

Here’s a video of me testing out a half assembled version of the device. I’m using inductive coils to create sound from the electromagnetic waves emitted from my computer and surrounding electronics. These sounds are being amplified and sent into a bass shaker speaker. The bass shaker is installed inside the metal box, and the gooseneck “arm” I’m holding onto is rumbling with the sound, as is the whole box.

I plan on embedding this device into a leather vest of sorts with buckles on the front for tightening and fastening. The coils will extend down the arms into gloves.

I perfboarded my preamp circuit for my thesis project, the EM Brace. I’m using this circuit to boost the electromagnetic frequency signals before they are sent into the larger 40-watt amp that I’ve showed in previous posts. The circuit uses two OPA134 chips, which are really great audio preamp chips, so the mono signal is getting boosted twice. I based the circuit on the original Chu Moy headphone amp & used this site for help with the power supply, which requires negative and positive voltage (+4.5v and -4.5v). On the chu moy circuit, I changed the feedback resistors from 10k to 100k on the first chip and 1M ohm on the second chip. This yielded substantially greater amplification. My initial signals are weaker than signals that would come out of, say, an iPod or computer, so I don’t think I would change these resistors if I was building a headphone amp, as the original schematic yields plenty amplification to drive a pair of headphones.

Yesterday I put together Ramsey’s UAM4 amplifier kit.

The amp is for my thesis project (see below). It’s an amazing amplifer. The board below is only 2.5 inches (!!), yet is able to produce 40watts mono or 20 watts stereo. It’s a partly surface mount unit, but not terribly difficult to put together. Just take your time, drink lots of water, stretch, and breath. Since it is a surface mount kit, you have to have tweezers, a magnifying glass, good solder, a small tip, some solder wick, and flux (this last one is a must). Don’t drink coffee either (jitters). Some of the capacitors are amazingly small, like I could fit dozens on my thumbnail. Luckily, the manufacturer supplies extra parts because sometimes the little pieces fly out of the tweezers and you can forget about finding them if they go far. I inserted my finger into the one of the pics below for scale.

This was my first surface mount work, and I have to thank p-comp allstars Todd Holoubek and Michale Chladil for their help.

Here’s the amp in action playing the Boredoms in stereo through two tactile transducers:

Here’s the slide show for my thesis midterm presentation. I haven’t blogged about my midterm in a while, and things have changed so here’s a quick update.

My thesis is tentatively called the EM brace, and it’s a wearable device for translating electromagnetic frequencies (EMF) into powerful sound waves that can be felt by the body. An antenna will be attached to the hand that can pick up EMF which will send those frequencies into a receiver/pre-amp that will turn the EM signals into audio waves. The audio waves will be sent into a powerful, compact amplifier which will give the signal enough juice to power some tactile transducers which will be attached to a brace structure that will wrap around the body. The tactile transducers are specially made to resonate whatever they are attached to, so the brace will vibrate strongly with the incoming signals.

I see this project as a way of engaging the body with the ambient electromagnetic signals that pass through us continually, as our bodies are essentially porous on a microscopic level. I’m still working out that kinks, so there will be more to come soon. Until now, enjoy the slideshow.

 

 MidTerm Presentation [0:14m]: Play Now | Play in Popup | Download

Despite being jetlagged and massive sinus pressure, I got a good bit of work done today. I’ve received only one of the two Fishman Powerjack endpin preamps I’ve ordered, but I got one conga drum to control max/msp/jitter today. I had to solder the 6-inch piezo film to the preamp, attach a 9V battery, and then secure the film and preamp inside the drum. The result is surprisingly good. This configuration makes a very sensitive and high quality microphone:

I then ran the output of the mic/preamp into an m-audio quattro interface, and into max/msp/jitter. Right now the patch is very simple. I’m using the peak frequency of the incoming audio amplitude adjust crossfading between two images, and things like brightness, color, and saturation:

At least things are talking, the actual effects can be modified later.

Also, I got a new aluminum pipe with a secure base flange to replace the pvc pipe on the old mike stand. I’m going to give up the twisting effect of the main pipe in exchange for structural integrity. The elephant will still twist, but the rest of the stand will be stationary. Other effects will have to be controlled via some onboard pots or something.

This week I am constructing the elephant microphone stand. It consists of pvc pipe on a wood base, and there is a potentiometer beneath where the pipe is attached which rotates when you twist the pipe. On top of the pipe is the base for the elephant stand, and again there is a potentiometer beneath this base so that when you twist the elephant stand the pot is twisted as well. Thus, the main pipe and the elephant stand can twist independently of each other, and when twisted a pot sends out values into arduino and into max/msp.

Since this is a mic stand, in max/msp I’m using those values to pan incoming vocals (by twisting elephant stand) and augment vocal pitch (by twisting main pipe stand).

I also got a temporary housing unit for the wiTilt. The circuit is constructed and fairly robust, but when I put it on the machete I’ll have to find a more subtle container.

Unfortunately, the congas have yet to arrive. The work the drums require though (placing piezo film beneath their heads, running them through pre-amp) isn’t too high so it won’t take too long to get that working.

Next steps: Once I get everything working and talking to max, I need to work hard on the max patch itself. Since my devices aren’t amazingly technical, the sound and visuals for the performance need to be well planned and of a high quality. Then we need to rehease the performance itself so that all the kinks get worked out.

This week has been pretty good. First off, I got my WiTilt from sparkfun. Following the instructions on the sensor workshop, I had no trouble getting the wiTilt’s data into Terminal. Getting the data into max and parsing it, however, proved not so easy. I could get the data in, but couldn’t get it to send continuously as the messages kept timing out. So then I tried downloading Woon Seung Yeo’s W2O, an app that parses the WiTilt’s data and sends it via OpenSoundControl into Max, but in her example patch she was using a deprecated object for receiving OSC data. I tried using Max’s built-in OSC reciever object, udpreceive, but things wouldn’t talk.

I finally found a patch via the Max/MSP forums that someone had made for the receiving and parsing the WiTilt data. Analyzing it, I realized that I was sending the wrong command (in ascii) to the WiTilt telling it send data. Problem solved. So now I’ve got a patch that takes in the witilt data wonderfully. I attached some oscillators to the incoming x,y,z data from the WiTilt, and the results are below:

Click To Play

Plus, I got the machete I’m going to use with the WiTilt. So one object/instrument is looking very good.

I also received a large elephant I ordered off ebay that is fairly light and i think it’s perfectly drillable for inserting a pot. I also got 20 panasonic WM-61A mics for the elephant after reading about them in “Getting a Bigger Sound” by Bart Hopkin and hearing them used in a live setting on this site.

These mics are really, really small. And there is a hack for the mics that prevents distortion under high sound levels that requires some really intricate soldering. I got one to work, but probably ruined 3 in the process. I’m not sure what to do with these things now. Wiring many of these seems like too much a time consuming task. I’ll probably give it another go though. I really need to put at least two or so on the elephant’s trunk.

I also got 5 or so OPA134 op-amps that I was going to run the mics into max with. They are typically used in DIY headphone amp circuits, but I figured they’d be plenty powerful for my needs. First tests weren’t successful, but I need to sit down and put more time into it.

Next week: Get mics/amps to work and then use them in max. Get hand drum to use with contact mic in max. Be optimistic.

My device for the instigation of change finds the inherent sonority of objects. It’s housed in a collectible Rambo lunch box, and the circuit takes a 9 volt battery. The signal is first sent through a 4093 nand gate oscillator chip connected to a 100k pot and a 1 megaOhm pot. The signal is then sent into a 4049 pre-amp/fuzz circuit, then into an lm386 op-amp, and then the signal’s voltage is kicked up by a radioshack audio output transformer. The signal is then sent out to two piezo discs/drivers. The piezos can be attached to other objects, and then used to resonate those objects.

The idea behind this is that the device is a hacked object that hacks other objects by turning them into mediums of sound/resonant bodies, supplanting their intended use-value in the process. Inspired by Walter Benjamin’s musings on “the collector”, I decided to use a collectible object to house the circuit in because I feel like collecting objects can be understood as a precursor to hacking objects in that collecting, like hacking, is an attempt at replace commodity value for values outside of the “cycle of exchange”. In the case of collecting, these values are personal and aesthetic, as for the collector the collected object is an art object to be displayed and embedded with the personal meanings (where i got the object, that time in my life, why i choose this object and not others). The object’s use-value and exchange-value are null and frozen within the collection.

The hacked object, though, is given different values. Its use-value is not null but transformed into other use-values and functions as determined by the hacker. New personal values arise as well, as the hacker feels a degree of control and closeness to this “new” object s/he has created, as opposed to the alienation (ala Marx) and distance between the consumer and commodity.

Click To Play

Click To Play