Computer improvisers! If a lot of the action during your performance happen’s on your computer’s display, join me in the Screen Capture mix on Weblogmusic! Here’s the first track: just improvise along with it, record your screen (you can edit your hands in too if you like), post it on YouTube and send us the link! Details at http://www.weblogmusic.org/
The classic Airstream trailer looks fast, even when it’s standing still. Architect Edward Noonan amplified this effect when he installed an Airstream trailer on the roof of the building at 1807 W. Sunnyside Ave., because he “didn’t want to haul an Airstream across the country to go do things.” (It’s officially named the Gentle Annie Stafford Pavilion and Conference Center.)
Only visible to passing trains, this stationary trailer embodies Noonan’s statement: you don’t have to go in order to do. To people sitting idly on the passing trains, they feel like the stationary ones, with the world—and the Airstream— slipping past them.
This piece gives florid flurries and jazzy lines to low instruments to reflect the juxtaposition of smooth lines and heavy materials in the Airstream. The electronic sounds are derived from audiovisual source recordings from the site. All sounds you hear are “carved” from the source recordings of trains passing the building, and melodic and harmonic contours are shaped by video material taken from the trains as they pass the trailer.
The culminating quirky jazzy tune is a transcription of the safety message heard on one of the trains. Its text harkens back to Noonan’s impulse to do something out of the ordinary, his stories of how it confused people and frustrated authorities, and ultimately allowed him to take the trailer where he really wanted to go. The message encourages you to “[be] observant of your surroundings” and “report any suspicious behavior or items,” with the key slogan, “If you see something, say something.” While on the surface it raises suspicion of anything nonconformist, you could also take as encouragement to watch for the quirks of life like the Airstream as you pass by, maybe go inside and follow where you mind wants to go, see what you see in your mind’s eye, and share it with the world.
Reference:
Kelly Kennedy, “An Airstream on a Roof?” Chicago Tribune, August 27, 2005, updated August 30, 2005, http://articles.chicagotribune.com/2005-08-27/news/0508270054_1_airstream-roof-train
The melody was taken from the recorded safety message played on the passing train: Continue reading
Voltage can be transmitted with little to no current because electromotive force and magnetic force are directly related. This is how we can send signals through outer space and how we can use magnets in microphones and guitar pickups to transmit sound electrically. So, voltage is important for these kinds of input transducers.
Because voltage can be created with little to no current, it is preferred for sending electrical power (V*I) over long distances. High voltage in power lines can be “stepped down” to 120V to increase current to meet the demands of appliances.
However, because voltage creates an accompanying magnetic field, if we transmit our audio signals at high voltage, they will interact more strongly with nearby magnetic fields along the way (e.g., other high voltage lines or devices). That is, our message won’t make it through in perfect shape.
Resistance decreases current, and when the current drawn by a device is constant, resistance makes voltage increase (like a thumb partially blocking the end of a water hose). Impedance is basically resistance, when considering AC circuits like those carrying sound waves. So, high impedance devices like electric guitar pickups and cheap consumer microphones send their signals with higher voltages and lower current than professional audio equipment. Their higher voltage means less power is needed for amplification, but the higher voltage signal is more susceptible to being affected by external electromagnetic interference. High voltage (high impedance) may be preferred when power is the main concern, but not when the quality of the signal—the message—is important.
So, it is preferred to send audio signals at low impedance, meaning high current and low voltage. Current is manipulated throughout a signal path in order to scale the voltage as needed to preserve the integrity of the signal represented by the voltage.
Device inputs are supposed to have impedance a about ten times as high as the impedance of the signal coming into it, sacrificing current in order to boost voltage while it is inside the device. This is like “zooming in” on the signal so the audio equipment can process it with greater precision.
As for actuators, transducers that convert electricity into sound, light, heat, movement, etc., it makes sense that power is needed: measured in Watts = Voltage * Current. So, they won’t work on little-to-zero current even if we can make high voltages as described above. Every device expects to draw as certain amount of current from a circuit. If the current is constant, specified by the device, then voltage scales the resulting power. Voltage is the answer tot the question, “How much?” in terms of loudness, brightness, speed, etc.
In short, you could say that voltage is the message, and current is the muscle.
Time
While modern citizens are busy keeping up with communications technology, they are missing out on many human elements in communication like presence and authenticity. While some say we will get used to life mediated by screens and some prefer to wait for technology to get fast enough so we can recreate some of those human elements, there is value for artists in exploring the expressive potential of liveness as a unique dimension in a performance. Aesthetic concepts are established to show what is lost when a performance Continue reading
Generative Art International Conference Continue reading
This tutorial by Blue Rooms shows how to make a pad pulse to the beat using a compressor with a bass drum as its sidechain input. This technique is pervasive in dance music and can be disorienting, hypnotic, or nauseating depending on how you use it. At the end of the video he shows how you can use a gate instead of a compressor to carve rhythms out of a sustained pad.