Sep 21 | Physics | Installation Gear

Read Before Class


In Class

  • Did everybody get the welcome email from the class list?
  • Collect files from the “Recording 101” exercise.
  • Expand the basic audio signal flow (which we introduced last week) to include playback.
  • Introduce the basic vocabulary of sound (Frequency, Amplitude, Spectrum, Duration).
  • See the excellent Acoustics and Vibration Animations – Dan Russell, Grad. Prog. Acoustics, Penn State
  • Demonstrate the cone-movement of a speaker with a sub-audible tone generated in MAX/MSP.
  • Observe sounds using onscreen graphs of the 4 aforementioned properties via analysis plugins inside Reaper audio editing software. (The oscilloscope was s(M)exoscope . The spectrum analyzer (MAnalyer) and tone generator (MOscillator) were from the MFree effects bundle. The spectrograph was a built-in Reaper plugin called gfxspectrograph.)
  • Observe interference patterns on the surface of water, agitated by a speaker, plus non-Newtonian craziness via the magic of cornstarch!
  • Introduce the installation equipment available from Dan in the editing room (players, amps, speakers, etc.)
  • Practice the ancient Zen art of cable coiling.


  • “Music For Piano With Slow Sweep Pure Wave Oscillators” by Alvin Lucier (From “Still Lives” CD, 2001)
  • Spectrographic “easter egg” in Aphex Twin’s “Equation”

Further Research

  • “Soundings” by Gary Hill
  • “The Queen of the South” by Alvin Lucier
  • In class today we used a subwoofer driver to vibrate a tray of water to explore cymatic phenomena. There are special drivers called “tactile transducers” (AKA “bass shakers” or “aural exciters”) that are designed to vibrate surfaces instead of air. Parts Express sells a wide variety of them. You can also use a piezo buzzer element and a small audio transformer to turn lightweight rigid surfaces into speakers. (See book Handmade Electronic Music by Nic Collins)
  • German artist Markus Kison used tactile transducers to hide sound in a metal railing overlooking a river in Dresden. In “Touched Echo”, listeners put their elbows on the railing and cover their ears. The sound conducts through their bones, revealing aural artifacts of the WWII bombing of Dresden.
  • “Wavetable” by veteran sound and media artist Liz Phillips
  • A very geeky Chladni plate Youtube video from Edwin Wise, also featured in MAKE Magazine. (Subscription required to view article. Ask me and I’ll print it out for you.)
  • In this extremely corny PBS video, you can see an alligator rippling the surface of water using only its low voice.
  • On the subject of sound analysis (and the mysteries of the deep): An array of underwater research microphones (AKA “hydrophones”) have detected several unexplained deep-ocean sounds over the years. “Bloops” have been recorded several times since 1997 and were eventually classified as the disintegration of icebergs. Maybe it’s a sea monster from pre-history? H.P. Lovecraft fans think it’s the stirrings of the ancient alien overlord R’lyeh and skeptics dismiss it as one of many unknown sounds in the deep ocean.
    NOTE: The NOAA hydrophone array that detected the “bloop” is a leftover Cold War surveillance system formerly called SOSUS. It was designed to detect and classify the sounds of Soviet submarines across the world’s oceans.
  • I do a lot of work with a visual programming language called MAX/MSP/Jitter (aka “MAX”). It’s part of a family of “patcher based” programming languages, which means that data flows through visual patch cords instead of lines of code. It was designed to emulate the way that early modular synthesizers worked, so electronic musicians could write computer software using skills they already had. You have probably never seen a modular synthesizer but many people find the patcher style of coding much friendlier than traditional textual coding. Here are some links:
    • MAX/MSP/Jitter – (Mac/Win) $$$, free trial and student discount
      Trivia: MAX is named after computer music pioneer Max Mathews.
    • PD (“Pure Data”) – (Mac/Win/Linux) free, open source
      Very capable but much uglier than MAX with a steeper learning curve. Created by Miller Puckette, who originally wrote MAX. (Download the version called “pd-extended” because it includes lots of optional things that are not present in the main distribution.)
    • Processing (Mac/Win/Linux) free, open source
      This isn’t a patcher-based language but I’d be remiss if I didn’t mention it. Processing is a very simple textual programming language based on Java. It’s a painless way to learn “real” programming and there is a huge community out there to help. It handles video and sound through external “libraries” that extend its basic functions. (Not as fast as MAX, PD for video and sound.)