Audio Art Show Construction
April 28, 2007
April 15, 2007
Force Sensing Resistor Experiments
We want to be able to sense how far people are pushing the poles in our installation. I thought we could do this by measuring how much force the PVC poles are exerting on the ring they're sitting in.
Since force sensing resistors from Interlink Electronics are expensive ($5-6/each) and also because I couldn't see how the fragile FSRs would fit into the holes we planned to use, I wanted to find a better solution.
I discovered it was possible to create FSRs out of wire and plastic wrap. Others have used conductive foam and wire mesh. Reading about linear position sensors also gave some insights.
I took 22 gauge wire from the physcomp lab, stripped it, and bent it back and forth to mimic the "fingers" on the FSRs I purchased from Interlink. After making two wire finger pieces, I wrapped one in seven layers of plastic wrap. I place the second set of wire fingers on the outside of the package and wrapped it into the existing package. My first few tests seemed very promising. When no pressure was applied to the package, the resistance was infinite. When I squashed the package, the resistance dropped down to about 10K.
The next trick was to try to duplicate this behavior on the end of a PVC pipe. We first tried applying the plastic wrap/wire packages around the end of the PVC pipe. The results were less encouraging than my initial experiments.
The homemade sensors were unreliable: either the sensor package was too tightly squashed between the PVC and the surrounding hole (and gave no resistance) or it was too loose and no amoung of bending the pole caused a reading.
April 10, 2007
Audio Art Show
The Audio Art class will present a show of our work on the 9th Floor of the Tisch Building on Sunday, April 29th from 5-8pm. Email me for further details.
April 09, 2007
PVC
On Saturday, Shlomit and I built another prototype of our audio art installation.
We went to Home Depot in search of bamboo and springs, but came back with 1/2" (ID) PVC and cast iron flanges.
The bamboo remains a cost-effective option ($1.79 for a package of 4-5 x 5' stalks).
We attached 3/4" x 1/2" reducing adapters onto one end of ~5' x 1/2" (i.d.) PVC pipes and screwed them into a 3/4" flanges mounted on a sheet of plywood. We painted the PVC poles hunter green to loosely reference a field of tall grass.
We created the prototype with two poles on it to see how the poles would flex as people move through them.
It was a great day to work outside and we were pleased with the progress we made.
Construction Lessons
- When cutting plywood, cut through the side you wish to display so the ragged edges are hidden
- Plan the flange installation better so the holes will line up on the top and bottom playwood pieces
- We will need to custom cut a 4'x8' plywood sheet to get the 6'x3' installation we want
Sound
We made further progress as we began to discuss the sound of the field. Both of us were drawn to the opening bars of Stravinsky's Rite of Spring. The was some initial confusion about whether we were listening to the "Rite of Spring" or the "Firebird Suite", but I resolved that as of this writing. The solo oboe (or perhaps clarinet?) provides a mysterious sonic backdrop for exploring a new space. We plan to edit a small sample from the first track and control its playback using the sensors we are planning to attach to the PVC poles. As users enter the installation, they will have the opportunity to push their way through our sound field. Each subsequent PVC pole they push will play the next piece of the sample we've chosen. If they walk push through the field at the right speed (according to the mood of the selected piece), they will hear the melody as they move.
April 07, 2007
Annotated Listening
Alice Planas and I have been investigating the idea of speech as music. The following is a summary of our in-class presentation from Friday, April 6.
Why?
- We've both done field recordings
- Alice interested in the creative potential in the raw content she's been capturing
- I want to see what can be done compositionally with speech as a "generator," for melody; many people seem to have musical voices
Process
- Tried two approaches initially: compositional & computational
- Attempted to write melodies from in-class recordings by listening and transcribing. This is time-consuming -- and made further difficult by the distraction of the meaning of the spoken words. Perhaps it is easier when you don't know the people who are speaking or don't care about the content of the discussion... but in our case we were too close.
- Attempted to create a pitch-following patch in MAX/MSP. The idea behind pitch-following was to separate the frequency spectrum into separate slots - ideally a half-step apart and then track which slot had the greatest energy level.
Pitch-Following Resources
- Fiddle - MAX/MSP patch for continuous pitch tracking
- Paper: Strategies for Continuous Pitch and Amplitude Tracking in Realtime Interactive Improvisation Software
- My earlier experiments
Listening Selections
Larry Austin - 3 tracks audio portrait of Joan La Barabara (obtained at Avery Fischer Media Center in Bobst Library)
Joan La Barbara - 73 poems
Thomas Buckner - "His Tone of Voice at 37"
Paul DeMarinis - Music as a second Language:"An Appeal"
Laurie Anderson - "NY Social Life" (requires NYU ID/password)
Bobby McFerrin http://www.youtube.com/watch?v=LtXrKo8Btfc
March 31, 2007
Sound Sculpture Links
Bertoia Sounds
- Clickable sound links on this page; these are rather bell-like sounds... clangy and mechanical, but they do have an interesting personality.
Bertoia Sound Sculptures
- An online catelog of sorts. Minimalist aesthetics.
Sonic Architecture
- Works from architects/designers Bill and Marv Buchen. Many are located around NYC.
March 30, 2007
Sensing Experiments
Today we experimented with different strategies for sensing the motion of springs. The first was inspired by electric guitar pickups. I thought we might be able to create an electromagnetic pickup to sense the vibrations in the springs. We tried to create a simple electromagnet out of a nail and some transformer wire.... oh, yes... and a power drill.
We scrapped the pickup idea after measuring the resistance of the coil to be 0 Ohms. I was concerned it might short something out. Shlomit also thought we would have more creative possibilities if we used sensors rather than capturing the sound of the springs directly.
Returning to a previous sensing idea, we experimented with a flex sensors.
Flex sensors are not ideal for our application; they only sense motion in one direction and require a fair amount of deflection in order to produce a useful reading. (note for the future... measurement ranges would be useful for documentation purposes)
We also considered mounting the springs on top of a pair of joystick potentiometers to sense X-Y movement. The miniature potentiometer we tried to use for our prototype was too stiff to yield useful results. We wrapped a copper wire around the dial of the potentiometer, hoping that motion of the springs on our installation mockup would move the potetiometer and generate a varying resistance. No luck.
Musical Speech
Another version of the musical speech patch. I spoke with Peter last week about fffb~ and made it work -- to some degree.
I ran into trouble finding the frequency bin with the maximum energy. Jonathan Marcus helped me with a solution to that problem using the zl object.
The patch makes some sounds now, but still not what I hoped for. I wanted a patch that would highlight the musicality of recorded speech. I expect it would work better on some voices than others, but so far it just sounds "random."
- When the .wav file is silent, the patch plays the last frequency in the frequency transform list (to fix, I will need to detect that case and turn off the cycle~ object)
- I tried testing the patch with the cycle~ object as an input, thinking that a pure tone would be a good way to test the patch's ability to recognize frequencies. As I changed the frequencies of the cycle~ object going into the patch, there were some spots where the pitch detection "blew up" and returned to the highest frequency in my list.
- More experimentation needs to be done with voice recordings to see how they respond. I will post some results soon.
Using the patch
- Enable the DAC
- Click the "open" message to load a file into the sfplay~ object
- Click the "1" attached the sfplay~ object to start playback
- The following controls modify the output: transform strength, wave volume, and transform volume
- "Transform Strength" controls the scaling of the values coming out of the fffb~. Increasing the transform strength with cause larger numbers to be packed into the frequency bin energy list. This primarily affects the height of the peaks on the multislider display.
- "Wave Volume" and "Transform Volume" adjust the relative sound levels of the original .wav file and the transformed signal. Set transform volume higher than wave volume to emphasize the transformed sound.
March 28, 2007
Final Project Progress
Shlomit and I made some progress on our audio art final. We decided to build a sonic field of springs.
Strategies for sensing movement:
- Flex sensor
- Magnetic pickup (like electric guitar)
- 2-axis potentiometer (joystick)
After brainstorming more about producing sound and sensing movement, we built a tiny prototype, using the technique I discovered while building a prototype for Designing for Constraints.
 |  |
March 23, 2007
Music Creation for Non-Musicians
Aaron Siegel and Chris Peck and were guest lecturers in Audio Art this afternoon. Both compose works for untrained performers. This is one of the reasons I came to study at ITP. I want to design systems to enable untrained performers to collaborate musically.
Aaron's piece "Work in Manufacturing" was a percussive piece with fixed rules, but varying outcomes regulated by each performer's breathing. The rules of the piece made me feel disoriented at times because I had to keep a number of things in mind: how times I had inhaled or exhaled since beginning my current "station," how many "stations" I had completed, and the number I had chosen as my "jump" number for selecting subsequent stations.
The overall sound of the piece was intriguing, but I prefer tonal music.
Chris' piece "Worried Long" was a "choral" piece. I found it easier to appreciate the quality of the sound in this piece because it was richer and sustained. It sounded majestic as we sang it. I was very surprised at how harmonic it sounded -- even though none of us knew the intervals we were supposed to sing. Further, only about half the class was musically trained. I don't know how many of us could say that we know how to sing, but I really enjoyed the sound we created and would definitely consider it music. The dynamics were incredible and it was invigorating to belt out the slowed down lyrics with the rest of the class as we reached the climax of the piece.
I've been thinking about the discussion Amit and I had about believability. Both of the pieces seemed to have that quality. I knew nothing of the two composers beyond their remarks prior to performing the pieces, but it seemed that each piece matched the personality of its composer. Additionally, it was believable that we were creating the music together. Neither piece asked us to make an "impossible" committments in performing them. Collectively, we had all of the skills necessary to render the works. There was no need to think about which performers would be capable of properly interpreting their parts.
Final Project Proposal
Shlomit and I are proposing a final project around visualizing the propagation of sound and exploring the physicality of sound.
One of our ideas is an installation which captures the evolution of sound in a space. Colored lights suspended from the ceiling of the space react to sounds created in the space. We draw our inspiration from the ephemeral quality of warm breath in cold winter air. As you exhale, a gentle fog issues from your lips into the surrounding air.
Other ideas surrounding this first proposal are issues of memory and the incarnational power of words. The words we speak and the words we hear are not mere acoustical vibrations. They carry meaning. What if we could see these vibrations as they occured? What if we could see lingering traces of these vibrations?
Our second idea is an installation where the viewer walks through a field of flexible reeds. As the reeds are pushed aside, pleasant sounds are created in the space.
Followup - Voices as Music
I spoke with Peter today about the difficulty I was having with the with fftin~ and fftout~ objects in MAX. He suggested I try the fffb~ object instead, which he used in the past to create a real-time frequency analyzer. I'll give it a try this weekend.
Response: Basic Concepts of Minimal Music
I'm not sure how to react to this reading. I don't think I've listened to minimal music, yet. Perhaps I should try to find some. Composers mentioned in the reading were La Monte Young, Terry Riley, Steve Reich, and Philip Glass. Perhaps the Avery Fischer Media Collection at Bobst has recordings. It would be even more ideal if there was a place online to listen -- and in fact there is. We have access to The Anthology of Recorded Music
I'll have more to say after I hear some.
March 16, 2007
Experiment - Voices as Music
I'm working to figure out how to analyze the dominant frequency of an audio signal. This takes me into the world of fft~. In an effort to avoid further reading, I search the MAX/MSP forums for audio to midi conversion.
This yields a patch called fiddle~ which is supposed to follow pitch. The fiddle patch appears to only run on Macintosh... it requires externals.
I return to the MAX/MSP documentation and try to puzzle over fft~. I read the tutorials in chapters 25 and 26. The documentation seems to present a progression. The fft~ object performs basic Fast Fourier Transforms, but doesn't take into account the overlap (?) of sample bins. I was skimming, so this is all a little unclear. All I'm looking to do is take frequency readings every "n" seconds in order to construct a "melody" out of some recorded speech. The tutorials seem to indicate I'll need to "window" my samples and that the pfft~ object takes this problem into account. There's even a diagram of a patch that shows how to read off the current frequency. The problem is, I don't know how to create an embedded subpatch for pfft~ to use. I try, instead, to create a named subpatch.
This works, but I found that the output I was sending out of the subpatch I create didn't change at all. Reading the tutorial more closely:
Note that in the above example the number~ object is used for the purposes of demonstration only in this tutorial. When DSP is turned on, the number displayed in the signal number box will not appear to change because the signal number box by default displays the first sample in the signal vector, which in this case will always be 0. To see the center frequency values, you will need to use the capture~ object or record this signal into a buffer~.
I added a capture~ object to the output of my test program, but this didn't work.
March 09, 2007
Reaction: Tuning Space
Quotes:
"Neuhaus aims for a tuning of sound and place as an expanded instrument"
- One of my interests is in the design of musical instruments that are readily playable in improvizational settings with very low barriers to participation.
"... making the experimental strand of musical practice susceptible to a different set of conditions and questions"
"Neuhaus invited an audience or listener to claim the work for him or herself."
"At that moment [Public Supply I] became a group activity -- a process of people making sound together, listening to it, and adjusting what they did according to what was going on. I think this is the heart of the musical process -- this dialogue"
- Yes. I tried an improvizational music-making experiment on Tuesday night in my Designing for Constraints class which explored a bit of this idea.
"Concentrating on this field of sound creates a heightened involvement with a given environment, as a means of cartographically locating sounds, their possible sources, and their meanings, not entirely as communicable message, but as an environmental condition"
- Seems to echo Pauline Oliveros' essay on deep listening. Listening becomes more than just concentrating deeply when experiencing music or sonic art. Perhaps I can make the comparison to an idea regarding drawing I read which related to the creative practices of Leonardo Da Vinci. I have experienced in drawing an understanding of the mechanics of that which I draw. Beyond the artistic composition of a drawing there lies a body of knowledge of the object of the drawing -- the way in which that object behaves: response to light, intersections of its components, the dynamics of its motion. The rendering of an object's image on paper draws upon this understanding. I wonder if the same is not true of sound: something of the structure and mechanics of an object are illuminated through careful listening.
"temporalizing space"
For further research:
Minimalism
February 24, 2007
Dia.Beacon
I drove up to Dia.Beacon with Alice, Andy, and Rory to hear Max Neuhaus' Time Peace Beacon. As I entered the building, I felt small -- dwarfed by the scale of the building and the ideas contained within it.
I found it interesting how Neuhaus' piece was able to dialogue with the ambient soundscape of the site without overwhelming it. I felt his sound successfully integrated with the sonic environment, transcended it, and left it different than before I heard it. Just as Peter had described in class, the absence of Neuhaus' piece once it finished left a space behind.
We created a comical incident while listening for Neuhaus' work. I became convinced at one point, while we stood in the semi-silence outside the cafe doors at Dia.Beacon, I was hearing a low-pitched throbbing sound. Its regular rhythmic rumble remained at the edge of my perception. I don't know what I heard, but it wasn't Neuhaus' work; after standing outside for 20 minutes, we finally decided to ask the museum attendants at the bookstore what we were supposed to be listening for. The piece plays at seven minutes to each hour and they claimed we would know when it was happening.
Back outside shortly before 3:53pm, we heard a train pass in the distance and wondered during the ensuing silence if we had been fallen for some big joke.
Then, almost imperceptibly, a tone began to emerge from the ambient sounds. I would describe it as a rich, sweet droning. It reminded me of a note sustained on a pipe organ -- majestic and vibrating. It was harmonically complex, yet seemingly a single tone. The tone grew in intensity and complexity. It was a beautiful sound, but only fleeting. It ended abruptly and yielded its place back to the existing environment.
I can't say how, but I felt the environment was changed somehow in those moments after the sound stopped. The sound's absence left behind a lingering memory and a heightened awareness of what my ears were now hearing. The sounds of the site seemed somehow amplified by the absence of Neuhaus' work.
What would this work be like if we hadn't been expecting it at all. Would we have been caught by surprise?
February 23, 2007
Noise
1. 
A short blast produced by applying envelopes to both the sound amplitude and to the resonant frequency.
Blast.wav
Blast2.wav
MAX/MSP Patch
2. Although this isn't strictly noise (in many regards, far from it)... I had the pleasure of listening for a few minutes to a talented performer in the subway.
Come Back to Me
3. For my distortion patch, I took the clean sample from #2, and played it backwards through Peter's simple distortion patch. CAUTION: this sample is very loud. Turn down your volume before playing.
UnpleasantDistortion1.wav
4. 
Here is a sputtering sound I've created using envelopes. I started off trying to make a simple beat patch using envelopes, but it started heading more in the direction of a sputtering noise.
sputter.wav
MAX/MSP Patch
Download samples as a package (excluding the field recording).
February 16, 2007
Filters, Delays, and Keycodes -- Hurray!
February 09, 2007
Reading Reactions - Week 3
Last week, Peter assigned us readings from John Cage and Luigi Rossolo.
Cage's thoughts on the need for new instruments in "the future of music: credo" parallel Rossolo's in "The Art of Noise." Both men anticipated the development of flexible synthesis techniques by which sounds of any character might be constructed. I'm not sure when Russolo wrote "The Art of Noise," but I imagine it was in the late 1800s. While he didn't have the technological vocabulary to describe some of the concepts Cage was promoting, he described synthesis in his own way.
I'm personally in favor of a hybrid of these techiques, where recorded sound combines with generated sound.
Cage's writing style intrigued me. I found I could read his section headings by themselves as a coherent statement or read them as introductions to the body paragraphs. I don't believe I've seen written composition like that before.
I didn't agree with Russolo's dismissal of all musical sound as banal. While his interests lay in moving farther and farther away from traditional music and into the complete freedom of pure sound, I continue to be moved by the live performance of music by a human person.
February 07, 2007
Digital Synthesis Techniques
Sample 1: Additive Synthesis
I started playing around with this right after class last week and had it in mind to make some sort of nasty sounding bass patch. I used envelopes to control the frequency and DC offset of the oscillators. I can't seem to predict, though, how the envelopes actually get used. The way I think it should work is that the metronome kicks off the envelopes and the frequencies I drew should be smoothly sent to the cycle~ object. That's what happens, except that the full envelope I drew doesn't get used.
 | 01 - Rumble.wav MAX/MSP Patch |
Sample 2: Ring Modulation
 | Ring Modulation.wav MAX/MSP Patch |
Sample 3: FM Fwub Bass
I modified Peter's FM patch to ramp the modulator amplitude between 20 and 250 over 1 second. This, in combination with the other modulation parameters, yielded a flappy bass sound.
Sample 4: FM Grow Tone
Using the FM synthesis patch again, but this time with different parameters, I created bass tone using a sine wave that evolved with a sound like a resonant filter sweep.
 | 03-FM_Fwub_Bass.wav 04-FM Grow Tone.wav MAX/MSP Patch |
Sample 5: Faux Scratch
I discovered an interesting sound by scraping the first modulator frequency between -20 and 20. It made the sound burble a bit and sound almost like a turntablist scratching.
 |
05 Faux Scratch.wav MAX/MSP Patch |
Sample 6: Blippy
Blippy, Atari-like noise sample. This one makes use of the modulo function to create the nasty repeating, yet random, blips.
 | 06 Blippy.wav MAX/MSP Patch |
Sample 7: Metallic Additive "Feedback"
I took a look in the MAX/MSP documentation folder and looked through the tutorial pages. There are tutorial topics on all of the synthesis techniques we looked at in class along with some helpful patches. I took the additive synthesis patch and started hacking away at it to see what I could produce. The tutorial contains a subpatch called "partial~" which encapsulates some of the basic elements of an oscillator so the patcher doesn't get so messy. The first patch I created with my modifications uses a fundamental frequency and makes two sets of tone clusters, one of which is subltey randomized. I find that this sounds a bit like feedback in a PA system, but with some interesting pulses caused by the beating of adjacent frequencies.
Sample 8: Metallic Additive Shimmer
One of the presets from the original MAX/MSP tutorial patch sounded interesting when I played it back through my modified version of the patch. I think it sounds a bitter like a metallic shimmer.
 | 07 Metallic Additive Feedback.wav 08 Metallic Additive Shimmer.wav MAX/MSP Patch |
Download all samples from this entry.
January 25, 2007
Assignment 1 - Listen Close
* Listen Close – Listen to a discrete repeatable sound. Listen for the detail in the sound.I couldn't find any good close-up sounds to listen to at the library, so I went back to ITP. I wanted to listen to something other than the relentless clacking of keyboards, shuffling feet on creaking hardwood floors, or mobile phone conversations. I wanted to listen to something simple, yet complex.
First stop -- the Equipment Room. (thanks, Andrew, for humoring my request for a piece of equipment that made an interesting sound) . I left with a Panasonic CT-1030M pro video monitor and the goal of capturing in words the experience of listening to it turn on. When I checked it out of the ER, I had been hoping for the metallic, fuzzy honk of the de-Gaussing circuit on my home Dell monitor. The Panasonic had no soul.
I returned the tv monitor and sat down by the Deer Park water cooler next to the men's room. This is the sound of water flowing from the spigot into a disposable plastic drinking cup.
There is a filtered, hollow sound as water drops into the empty cup. Air bubbles spatter as they burst at the surface of the water. The valve hisses slightly while it is open. When my head is against the base of the water cooler, I hear a hard muted reflection of the plastic valve as it opens and closes at my touch.
I pour water from the cooler into a stainless steel thermos and note the metallic "spang" of the water in the deeper cavity. As the water rises, one set of frequencies increases while another decreases. I enjoy the sound of the metal thermos as I flick it with my finger tip. "Bloing" "Buwoing" The frequency changes as I move the thermos around and the water within it sloshes back and forth.
Assignment 1 - Listen Far
* Listen Far – spend 5 minutes in an undistracted setting. Park bench, your apartment, or a street corner. Listen. Listen to the faintest sound you can hear. Now try to listen beyond that sound.Bobst Library, Second Floor -- seated at a table facing away from the central lobby. My ears are toward the reference area where students are typing.
Immediately above my head, the HVAC system rumbles.
I hear the electronic ding of the lobby elevator out in the central lobby. It reverberates briefly against the smooth tiled surface of the lobby floor. I am seated in a carpeted area, so the sounds immediately around me are muffled.
A door slams ("guuuhm") in the distance and its echo lingers in the lobby area.
I hear light female footsteps, the sharp attack of boot heels against the tile ringed with bright reverberation. They approach and become slightly muffled on carpet. They come up the stairs located behind me then continue further up until my listening is interrupted by someone whistling a melody out in the lobby. I presume it's the lobby by the reverberation.
As I look over my left shoulder, I see a young woman typing at a Macintosh computer. I can hear the faint mechanical clacking of the keys from her keyboard even at a distance of 50 feet. I wonder if I can hear anything beyond the sounds of her typing. Can I hear her shift in her chair?
She doesn't move.
I wonder what my experience would be like if I could hear the whirring of the hard drive in the computer in front of her.
A pen falls ("taakkkk") onto the surface of a desk in front of me and my focus changes.
I'm aware of the difference in frequency responses between my right and left ears. Last semester, a large mass of wax built up inside my right ear. It's starting to happen again. The high frequencies are not as bright in my right ear as they are in my left. It's time to start using the Murine again to loosen the wax.
A sneeze echoes from the lobby.
How deafening the world would be if louder if I could hear the hard drives spinning -- the rustle of clothing -- the scratch of pen or pencil against paper... What if the lowest frequencies were perceptable -- the atoms in the objects at rest: books, maybe still echoing with the sound of the typesetting equipment that deposited the ink upon their pages.
Then I would be listening deeply and I would understand.
First Class
Our first reading assignment was Quantum Listening by Pauline Oliveros.
I have to admit that the structure (or apparent lack of) made it very difficult for me to read. I had a very hard time following her train of thought. Thanks to Rob Faludi's BlogBlender, I discovered Gian Pablo's reaction to it which encourages me to read it in a different way. Despite having played music for years, I had not considered reading an essay as music before.
Some of the themes she discussed with respect to deep listening reminded me of Aaron Copland's What to Listen for in Music and also of Barry Green's The Inner Game of Music
I wondered what she meant by "practice practice", though.
Two things about her essay resonated with me.
1: the desire to create music collaboratively with people who don't have formal musical training. To this end, I may try out to work out a "simple set of rules" by which we can do this in my Living Art class.
2: when I was in college and worked in a recording studio, I began to experience a deeper listening than I had ever done before. Part of my job was to verify that transfers we made from digital audio tapes (DATs) into ProTools didn't contain glitches. I listened to the recordings very intently through headphones and through the process, I began to hear details I hadn't experienced before. I developed a deeper sense of appreciation for clarity and fidelity in recordings.
-