The point of my blog post today is to signal my thinking about how embodied interactions produce meaning for a interactive art work. In particular, I was really inspired by Dourish's discussion of meaning and phenomenology that was referenced by Dalsgaard and Hansen in their "Performing Perception paper." Dalsgaard and Hansen summarize Dourish's point as follows: “…we can however deconstruct the systemic
concept of embodiment to gain an understanding of some of the tensions between
user and system. First and foremost, it
is a relationship characterized by the user’s exploration of the meaning of the
system…Second, meaning is not a constant, rather arises from the user’s interaction
with the system…this implies that one cannot control what the system means to
the user, only influence the construction of meaning” (Dalsgaard, 5).
I looked up Dourish's 2001 paper "Seeking a foundation for context-aware computing" and found this memorable quote that provides a theoretical ground for the construction of meaning through action, paraphrasing Heidegger essentially: “it is through our actions in the world—through
the ways in which we move through the world, react to it, turn it to our needs,
and engage with it to solve problems—that the meaning that the world has for us
is revealed…action precedes theory; the way we act in the world is logically
prior to the way we understand it.” (Dourish, 6)
This theory leaves open the possibility of multiple and evolving meanings for a piece of interactive art. This would be most true if we are fortunate to have a community form around a piece of art, as Dourish argues: “if the meaning of use of technology
is…something that is worked out again and again in each setting, then the
technology needs to be able to support this sort of repurposing, and needs to
be able to support the communication of meaning through it, within a community
of practice.” (Dourish, 12).
Friday, March 25, 2016
Saturday, March 19, 2016
The Humidity of Emotion -or- That Feel
At the risk of stretching myself too thin, I've decided to take on an extra layer for the upcoming installation project. This class is at it's core about interactive design; our charge is to conceive of and execute robust interaction frameworks. This involves, but is not limited to, ease of entry (meaning little or no explication of the rules of the interaction), richness of recognized gestures or interaction possibilities, feedback from the installation that both maps to the gesture intuitively yet is also dense enough to maintain the interest of the participant, seamless technical execution, an error handling framework for unexpected input (following Benford et al in the paper "Sensed Expected Desired"), and many more. While this is more than enough to fill my plate for the next five (!) weeks or so, I also feel compelled to explore another layer that is not the main focus of (but by no means ignored in) this class: that of a compelling aesthetic experience causing an emotional connection with the audience.
I will by no means claim any sort of authority on the width and breadth of interactive artwork, but I have seen a fair share, some good, some bad. Many, and especially those that harbor a large amount of digital hardware and software, often have an antiseptic feel to them, a sleek presentation that shares an aesthetic with the design of all of our technical hardware. In a discussion with Dr. Gurevich about this, he suggested that many of the works are still conceived of in the vein of the Bauhaus, Late Modernism and Minimalism, with their rejection of of superfluity and unnecessary ornament. I am by no means rejecting this aesthetic, this is not a manifesto and I shy away from categorical imperatives; I am just curious if a more emotive framework can be found for a digital interaction. While many works are able to instill a sense of wonder with beautiful lights, surprising interactions and technical sophistry, or conversely deep disquiet with dark imagery, it's rare, at least for me, to find a digital work that can, or attempts, to achieve more subtle explorations of emotion. Is there a path to Nostalgia, to Ennui, to Anticipation, to Longing, or to the vast sea of feelings that are as of yet unnamed, only evoked through either the actual experience or the non-verbal forms of communication? C.J. Ducasse in a 1964 article in the Journal of Aesthetics and Art Criticism puts it well:
I was reading on the basic psychological aspects of a viewers emotions in relation to art when I came across an article by Vladimir J. Konečni of the Department of Psychology at University of California San Diego (Emotion in Painting and Art Installations, The American Journal of Psychology). The article was about how, overall, installation art was a better vehicle for instilling an emotional reaction in a viewer than traditional painting. Most of his conclusion boiled down to how installation work can be made very large and thus short circuit its way to inducing awe. A line early in the paper caught my eye:
Svankmajer is a Czech filmaker working from Prague most active in the mid to late Communist era. He is most known for his surrealist stop action animation made on a shoe string budget with found objects. The Brothers Quay, twin brothers from the U.S. but located in England, created a similar style, though they came to Svankmajer late as his works were hidden behind the Iron Curtain. They made a tribute film to Svankmajer called The Cabinet of Jan Svankmajer Here are some examples of their work:
A Svankmajer whimsy:
Jan Svankmajer - Jabberwocky from deanna t on Vimeo.
And an excerpt from the Brothers Quay:
These works have an emotional resonance for me not just because they are technical feats, or the peculiar medium that they choose to work in, but because they are rich with sign; obviously they are in direct succession of the surrealists for whom subconscious sign was a stock in trade. The reuse of weathered detritus, the juxtaposition of objects and actions not normally related, the bizarre narrative, the surreal settings; all these combine to create an atmosphere 'humid' with sign just waiting for for a subject to condense on. Just like the water suspended in humid air, the condensation is indiscriminate because it is pervasive; a cold spoon, a glass of ice water, a window, anything just cool enough will cause the water to appear out of the air and saturate it's surface. To follow the metaphor, as long as one is willing to accept the indiscriminate condensation as the desired affect and not simply targeting one 'object' (feeling) to saturate, then creating an atmosphere that can have emotional resonance across a variety of subjective viewpoints is possible.
This is dangerous territory. Just like pointing at a certain feeling can backfire, creating an overbearing overall environment can cause a viewer to shut off due to too much stimulus; furthermore just collecting a heap of sign laden imagery and cramming it into a container risks becoming kitsch. The collection must be delicately curated or the 'dew point' of the whole enterprise drops and the water falls out of the air.
Then there are the requirements for this particular situation. This is an exercise in interaction, requiring and active as opposed to a passive audience. It would do no good to do the curation of sign and then simply give the participant a push button interface; this would also break the atmosphere, drop the dew point. The interaction must be interwoven into the atmosphere, inform it, work seamlessly within its confines. This brings me to the question that is the whole point of this endeavor. Our subconscious is activated by our different senses in a myriad of ways with more or less efficacy; the smell of rotting leaves, the mournful wail of a saxophone, the taste of a childhood dish, the quality of bright sunlight of a late winter afternoon, etc. Sight, smell, hearing and taste seem to have a direct line to the subconscious, cutting across our years and ringing out multiple associations in their path, creating a complex and unrepeatable tone of feeling with each pass. But what of touch? What of the tactile? What of gesture? There is something so immediate about touch that it seems to defy these subconscious associations; I'm racking my brain trying to think of a nostalgic gesture, of a texture that sends me into reverie, the touch equivalent of Proust's Madeline. This would be the gold standard of Interactive Design; not just interacting in a sign saturated atmosphere but having a physical interaction saturated with sign. This is my big lift for the upcoming project and it may very well turn out Quixotic. I'll leave the conclusion to one of our times great tradesman of sign, who once in an interview described himself as less of a musician and more of a curator:
I will by no means claim any sort of authority on the width and breadth of interactive artwork, but I have seen a fair share, some good, some bad. Many, and especially those that harbor a large amount of digital hardware and software, often have an antiseptic feel to them, a sleek presentation that shares an aesthetic with the design of all of our technical hardware. In a discussion with Dr. Gurevich about this, he suggested that many of the works are still conceived of in the vein of the Bauhaus, Late Modernism and Minimalism, with their rejection of of superfluity and unnecessary ornament. I am by no means rejecting this aesthetic, this is not a manifesto and I shy away from categorical imperatives; I am just curious if a more emotive framework can be found for a digital interaction. While many works are able to instill a sense of wonder with beautiful lights, surprising interactions and technical sophistry, or conversely deep disquiet with dark imagery, it's rare, at least for me, to find a digital work that can, or attempts, to achieve more subtle explorations of emotion. Is there a path to Nostalgia, to Ennui, to Anticipation, to Longing, or to the vast sea of feelings that are as of yet unnamed, only evoked through either the actual experience or the non-verbal forms of communication? C.J. Ducasse in a 1964 article in the Journal of Aesthetics and Art Criticism puts it well:
"The fact is that human beings experience, and the works of art and indeed works of nature too express, many feelings besides the ordinarily thought of when the term the emotions is used. These other feelings are too rare, or too fleeting, or too unmanifested, or their nuances too subtle, to have pragmatic importance and therefore to have needed names."So to what ends do I pursue in search of these subtle shades? It, of course, ultimately breaks down to 'that feel', the artistic judgment of the worth of an aesthetic, of whether or not is the correct vehicle for the feeling that I would attempt to invoke. In other disciplines, the access to that feel can be a much clearer pathway; there are hundreds, even thousands, of years of practice and tropes to follow or flee from. In the realm of digital interactive art, we barely have fifty or sixty years, maybe with a hundred years of antecedents; we have no history from which to draw or to be ashamed. So this has lead me down some curious pathways; as any place is as good to start as any other, I decided to start at what I though was the beginning.
I was reading on the basic psychological aspects of a viewers emotions in relation to art when I came across an article by Vladimir J. Konečni of the Department of Psychology at University of California San Diego (Emotion in Painting and Art Installations, The American Journal of Psychology). The article was about how, overall, installation art was a better vehicle for instilling an emotional reaction in a viewer than traditional painting. Most of his conclusion boiled down to how installation work can be made very large and thus short circuit its way to inducing awe. A line early in the paper caught my eye:
For an examination of their potential effect on emotion to make analytic sense, it is necessary that paintings be considered solely qua artworks – that for any observed effect to be treated as positive evidence, it needs to have been clearly caused by the paintings’ artistic attributes alone and not by their status as semiotic signs. An example isSo, setting aside the notion of 'solely qua artworks' and their utility to psychology (and I may quibble with his conclusion a bit—there is a Rothke at the Detroit Institute of Arts that still flabbergasts me every time I sit with it), I explored the idea of the 'semiotic signs' of the artwork. For Konečni this 'taint' of external meaning of the artwork made for a bad sample set for the sake of psychological research, but it could prove rich loam in my pursuit. Representational painting of course needs a subject, and I believe that a painter rarely chooses a subject solely based on the underlying set of signs and assumptions that portraying it would convey; being married to a painter I know it is an esoteric mix of quality of light and color that really catches their imaginations. Even if there is a conscious underlying meaning, like, for example, Picasso's Les Demoiselles d'Avignon, it is done more for immediate commentary or effect; the emotional signs, the unnamed feelings evoked are subjectively imbued into the painting by the individual viewer much later, and often to the distress of the artist. Furthermore, the deliberate invocation of a specific sign pointed at a specific feeling is ham-fisted, coercive, and inevitably bound to backfire because of the ultimately subjective nature of feeling. But I believe that it is possible, especially in a medium as flexible as interaction, to create a 'saturated atmosphere of sign'. No mean feat, I'm sure, but possible; I believe the place to look to for inspiration is film because it shares a similar combination of abilities in combinations of sound and light. A particular continuum of filmmakers comes to mind when I think of the aesthetic I would like to pursue; that of Jan Svankmajer and his immediate heirs, the Brothers Quay.
a portrait of a loved person, no longer living. Perusing such a painting, one may become genuinely sad, which, however, may have little or nothing to do with the painting’s artistic or aesthetic value, or even mimetic success. The painting does not induce emotion as a work of art, but as a displaced or generalized classically conditioned stimulus.
Svankmajer is a Czech filmaker working from Prague most active in the mid to late Communist era. He is most known for his surrealist stop action animation made on a shoe string budget with found objects. The Brothers Quay, twin brothers from the U.S. but located in England, created a similar style, though they came to Svankmajer late as his works were hidden behind the Iron Curtain. They made a tribute film to Svankmajer called The Cabinet of Jan Svankmajer Here are some examples of their work:
A Svankmajer whimsy:
Jan Svankmajer - Jabberwocky from deanna t on Vimeo.
And an excerpt from the Brothers Quay:
These works have an emotional resonance for me not just because they are technical feats, or the peculiar medium that they choose to work in, but because they are rich with sign; obviously they are in direct succession of the surrealists for whom subconscious sign was a stock in trade. The reuse of weathered detritus, the juxtaposition of objects and actions not normally related, the bizarre narrative, the surreal settings; all these combine to create an atmosphere 'humid' with sign just waiting for for a subject to condense on. Just like the water suspended in humid air, the condensation is indiscriminate because it is pervasive; a cold spoon, a glass of ice water, a window, anything just cool enough will cause the water to appear out of the air and saturate it's surface. To follow the metaphor, as long as one is willing to accept the indiscriminate condensation as the desired affect and not simply targeting one 'object' (feeling) to saturate, then creating an atmosphere that can have emotional resonance across a variety of subjective viewpoints is possible.
This is dangerous territory. Just like pointing at a certain feeling can backfire, creating an overbearing overall environment can cause a viewer to shut off due to too much stimulus; furthermore just collecting a heap of sign laden imagery and cramming it into a container risks becoming kitsch. The collection must be delicately curated or the 'dew point' of the whole enterprise drops and the water falls out of the air.
Then there are the requirements for this particular situation. This is an exercise in interaction, requiring and active as opposed to a passive audience. It would do no good to do the curation of sign and then simply give the participant a push button interface; this would also break the atmosphere, drop the dew point. The interaction must be interwoven into the atmosphere, inform it, work seamlessly within its confines. This brings me to the question that is the whole point of this endeavor. Our subconscious is activated by our different senses in a myriad of ways with more or less efficacy; the smell of rotting leaves, the mournful wail of a saxophone, the taste of a childhood dish, the quality of bright sunlight of a late winter afternoon, etc. Sight, smell, hearing and taste seem to have a direct line to the subconscious, cutting across our years and ringing out multiple associations in their path, creating a complex and unrepeatable tone of feeling with each pass. But what of touch? What of the tactile? What of gesture? There is something so immediate about touch that it seems to defy these subconscious associations; I'm racking my brain trying to think of a nostalgic gesture, of a texture that sends me into reverie, the touch equivalent of Proust's Madeline. This would be the gold standard of Interactive Design; not just interacting in a sign saturated atmosphere but having a physical interaction saturated with sign. This is my big lift for the upcoming project and it may very well turn out Quixotic. I'll leave the conclusion to one of our times great tradesman of sign, who once in an interview described himself as less of a musician and more of a curator:
Thursday, March 17, 2016
Space - Installation I
As we begin our installation projects, I've become very preoccupied with this idea of space and concept. Of course, as interactive sound/visual/music/media/experiential/whatever-label-you-want-to-put-on-it artists it's hard to be not preoccupied with space. This is obviously coming from a rich tradition of artists such as Lucier and Cage who were focused on the concept of space and related ideas. But when I was coming up with initial ideas for this installation, I noticed that my ideas could more or less be sorted into two categories: object-based installation, and space-based installation. An example of object based installation was my balanced-spatialization cube, where the spinning of the cube controlled amplitude and sonic placement. An example of space-based installation was this idea of hanging sheets, or swaths of cloth in Davis--where the entire room/environment is involved in the installation. I'm definitely leaning more towards space-based installation at the moment, and have a couple of ideas that I'm currently running with an trying to elaborate on.
So as I think about how I want to transform a space into an installation or (better word in my opinion) experience, I've been kind of struggling with how to properly infuse concept so that the interaction itself is meaning. So that my use of the space has meaning, and I'm utilizing the space to best of the installation's purposes. The space should be an integral part of the installation, not only in terms of interaction but also for meaning. As I try to elaborate on these space-based installation ideas, I'm trying to keep in mind concept and meaning. Because of this, I've been doing a lot of "outside" (not-for-school) reading, exploring, word association, etc. to try and find ways of making space-object-interaction connect in a meaningful manner. I think I'm getting there slowly, but when you're in the steady pound that is school, it can be hard to remember that taking time to ruminate and reflect is still a valuable part of the development of not only my project, but my artistic identity.
A few gallery works/installations that I'm feeling inspired by:
Shaping Shapce: 17 Screens by Ronan and Erwan Bouroullec
Not an interactive piece in the way that we envision interaction, but still interesting in terms of shape/material/concept.
Unfolding - Kimsooja
I saw this exhibit in Vancouver a couple of years ago, and there was one room in particular that stuck out to me. It was a large room, and there was just hanging Korean-cultural blankets. And I have a very vivid memory of weaving my way through the rows and rows of blankets--all incredibly colorful, and I have a vaguer memory of different smells in that space. There's something about the hazy memory of a hazy memory; identity lost and found in those spaces; cultural impact; mixed-cultural identities; remembering something that was but is no longer...
Just things I'm thinking about...
So as I think about how I want to transform a space into an installation or (better word in my opinion) experience, I've been kind of struggling with how to properly infuse concept so that the interaction itself is meaning. So that my use of the space has meaning, and I'm utilizing the space to best of the installation's purposes. The space should be an integral part of the installation, not only in terms of interaction but also for meaning. As I try to elaborate on these space-based installation ideas, I'm trying to keep in mind concept and meaning. Because of this, I've been doing a lot of "outside" (not-for-school) reading, exploring, word association, etc. to try and find ways of making space-object-interaction connect in a meaningful manner. I think I'm getting there slowly, but when you're in the steady pound that is school, it can be hard to remember that taking time to ruminate and reflect is still a valuable part of the development of not only my project, but my artistic identity.
A few gallery works/installations that I'm feeling inspired by:
Shaping Shapce: 17 Screens by Ronan and Erwan Bouroullec
Not an interactive piece in the way that we envision interaction, but still interesting in terms of shape/material/concept.
Unfolding - Kimsooja
I saw this exhibit in Vancouver a couple of years ago, and there was one room in particular that stuck out to me. It was a large room, and there was just hanging Korean-cultural blankets. And I have a very vivid memory of weaving my way through the rows and rows of blankets--all incredibly colorful, and I have a vaguer memory of different smells in that space. There's something about the hazy memory of a hazy memory; identity lost and found in those spaces; cultural impact; mixed-cultural identities; remembering something that was but is no longer...
Just things I'm thinking about...
The Luminator
And here is my final instrument! I thought it'd be good to have up on here for the courses's documentation purposes. Light-based electroacoustic instrument--you can check out all the fun details at http://fidelialam.com/the-luminator
Friday, February 26, 2016
Room Prep for Ambisonics, or the Many Ways To Bake a Pi
In further preparation for an ambisonic performance in the Davis studio, I undertook a fairly exacting survey of the speaker positions in the room in order to use the information to fine tune the ambisonic 'sweet spot'. This is a short description of my methods and results.
One thing I have learned implementing this project is how to translate between various 'azimuth' orientations depending on which coordinate system and compass orientation each system uses. For example, my sensor gives out Euler angles in relation to gravity and magnetic north; on the other hand the ambisonic library's map function uses compass agnostic Cartesian coordinates or Polar coordinates. The Cartesian coordinates of a sound position have to be extrapolated from the angles sent by the sensor using various trig manipulations. Or if I choose to go polar coordinates, 0 degrees is to the right side of the graph on the 'x' axis. This presents confusion when orienting the project because on a magnetic compass 0 degrees is north, which happens to be the 'back' wall of the Davis studio. Furthermore, the polar system doesn't operate in degrees, but in Radians, so a translation has to be made there as well. Lastly, with the 'front' of house being due south, the speaker numbering system starts with the center speaker over the top of the projector screen.
For Ambisonics, the Davis studio presents an 'irregular' (though mildly so) loudspeaker arrangement. Ideally for Ambisonics, a evenly spaced circular array of speakers is ideal, but there are compensations written because this is rarely the case in real world situations. The authors of the library I am using described their method in this paper from the 2014 ICMC. Their description of the solution is "...we implement an algorithm that combines Ambisonic decoding and standard panning to offset the missing loudspeakers. With this technique we can go up to any high order and adapt the decoding to many loudspeaker configurations. We made tests for stereophonics, quadraphonic, 5.1 and 7.1 loudspeaker systems and other more eclectic configurations at several decomposition orders with good perceptual results."
The practical implementation in the library for irregular speaker arrangements takes the number of speakers and the progressive angle of the speakers and recalcualtes the decoding as described above. Here is a screen shot of the help file:
I have two goals going forward for this. With the relationship of the speakers to the center of room now established, I'm going to go around and see, and maybe adjust, the angle of address of the speakers to tune them to the center of the room. I also intend to double check these measurements and then prepare them into a detailed picture that can be kept on hand for further work and learning in the Davis Studio.
BREAAAK!
One thing I have learned implementing this project is how to translate between various 'azimuth' orientations depending on which coordinate system and compass orientation each system uses. For example, my sensor gives out Euler angles in relation to gravity and magnetic north; on the other hand the ambisonic library's map function uses compass agnostic Cartesian coordinates or Polar coordinates. The Cartesian coordinates of a sound position have to be extrapolated from the angles sent by the sensor using various trig manipulations. Or if I choose to go polar coordinates, 0 degrees is to the right side of the graph on the 'x' axis. This presents confusion when orienting the project because on a magnetic compass 0 degrees is north, which happens to be the 'back' wall of the Davis studio. Furthermore, the polar system doesn't operate in degrees, but in Radians, so a translation has to be made there as well. Lastly, with the 'front' of house being due south, the speaker numbering system starts with the center speaker over the top of the projector screen.
For Ambisonics, the Davis studio presents an 'irregular' (though mildly so) loudspeaker arrangement. Ideally for Ambisonics, a evenly spaced circular array of speakers is ideal, but there are compensations written because this is rarely the case in real world situations. The authors of the library I am using described their method in this paper from the 2014 ICMC. Their description of the solution is "...we implement an algorithm that combines Ambisonic decoding and standard panning to offset the missing loudspeakers. With this technique we can go up to any high order and adapt the decoding to many loudspeaker configurations. We made tests for stereophonics, quadraphonic, 5.1 and 7.1 loudspeaker systems and other more eclectic configurations at several decomposition orders with good perceptual results."
The practical implementation in the library for irregular speaker arrangements takes the number of speakers and the progressive angle of the speakers and recalcualtes the decoding as described above. Here is a screen shot of the help file:
You can see to the right of the main objects some umenus for channels and angles. Also, inside the hoa.2d.decoder~ you can see flags for mode irregular, channels and angles. I haven't implemented this yet, but it looks from the help file that the array starts at the top of the circle and progresses around clockwise in a compass style, as opposed to a polar radian or cartesian -pi,pi arrangement. (the optim~ object above the decoder object is also important for irregular arrangements, it's utility is also addressed in the paper.)
So all that is left to do is to find out the angles of the speakers in relation to the room. I did this first by establishing the very center of the room. I marked this with masking tape and in the future it may be valuable to actually add a permanent paint spike at the spot. After that I went around the room with the laser ruler and took the distance from the cone of the speakers to the north and the west walls. I then subtracted those numbers from the wall to center of room distances to position them in an x-y relationship with the center of the room I then did the operation arctan(opposite/adjacent) to get the angle measurements of all the speakers in relation to the 0 degree line represented as the line between the center of the room and the center speaker over the screen. As the room is fairly symmetrical over that line, I assumed the east side of the room to have roughly the same measurements as the west side of the room. Although it isn't needed for Ambisonics, I also ran the numbers through Pythagoras to get the distance from center of room to the speaker cone for future reference; I believe VBAP likes to have that number.
Here's the results:
- 0 degrees, 15' 2'
- 68.7 deg, 15.65' ( and 7)
- 113 deg, 15.6' (and 6)
- 161 deg, 15.1' (and 5)
I have two goals going forward for this. With the relationship of the speakers to the center of room now established, I'm going to go around and see, and maybe adjust, the angle of address of the speakers to tune them to the center of the room. I also intend to double check these measurements and then prepare them into a detailed picture that can be kept on hand for further work and learning in the Davis Studio.
BREAAAK!
Thursday, February 25, 2016
We have a spinning wheel, baby!!!!!!
So I constructed the first wheel. Learned a lot about steel pipe, galvanized pipe, stainless steel, the art school. Lots of things you can and cannot do in these areas. But I sucessfully created a base, leg and arm for the spinning wheel. The bearings I ordered didnt come in yet, but i think its spinning well enough with my new end caps. So I am going to see how those last.
Next is to see what kind of light data spinning wheels even give a photocell!!! Hopefully something!!!
Next is to see what kind of light data spinning wheels even give a photocell!!! Hopefully something!!!
Saturday, February 20, 2016
Ambisonics
I've still got a little bit of build to go, but I'm focusing on the sound creation this week. I think my project can be used in a variety of ways, but one of my biggest interests is the spatialization of sound, recreating 3D sound environments and manipulating them; I think my project lends itself very well to this application. The nature of the interaction with the Bucky is hemispherical, with the round outer edge easily translating to the horizon and the various motions back and forth from the edge mapping nicely to an overhead dome. The data that comes from the onboard ITU maps fairly easily to the coordinates of a virtual soundfield as I showed in my previous post. The next step is figuring out how to implement the virtual soundfield. I had already had a specific library picked out in MaxMSP, but in a conversation Dr. Gurevich brought up a competing implementation, so I thought I should take a look at the two for the sake of thoroughness.
The method I was planning on using is one that I have used before, but only in a binaural (headphone) implementation; that is the method known as Ambisonics. The other method is a slightly newer system called Vector Based Amplitude Panning (VBAP). They both have their strengths and weaknesses and I'll try and survey a few of them here. The VBAP system was developed by Ville Pulkki who I believe is based in Helsinki. Through my very cursory research VBAP seems like an approach based on the traditional stereo field panning concept, where the ratio of the intensity of sound coming out of two speakers gives the perception that the sound is actually somewhere in between the two speakers. VBAP is a system that allows you to extend this system out to any number of loudspeakers. Using vector based mathematics to set the relative position of the sound and the combining it in a matrix with the loudspeaker position and distances, a convincing, easy to manipulate virtual soundfield can be created. Like the stereo system, it uses ratios of intensity to position the sound, but instead of a stereo pair, it uses stereo triplets, with loudspeakers above the plane, to give elevation information. It also smooths the transference of sound from one set of triplets to the adjacent triplets in order to involve the full range of motion.
Ambisonics, on the other hand, is much less intuitive 'under the hood' but instead uses some very cool psychoacoustics that I just barely understand to achieve the spatialization effect. It's an expansion of Alan Blumlein's invention, the Mid-Side microphone technique. Instead of the VBAP technique of actual localization of the sound in a triplet of loudspeakers, the position information is encoded in and emanates from ALL of the loudspeakers through a system of phase cancellation and correlation (I think...even after reading it a hundred times it still seems like magic to me. Probably why I'm a sound lover, this stuff just fascinates me). Ambisonics necessitates encoding and decoding stages on either side of the position determination, which can be processor intensive; this is one of the reasons that 5.1 Surround has surpassed Ambisonics for surround sound in consumer electronics. Up until recently the processing power needed put the decoder price point way out of range for anyone but enthusiasts.
The two systems, as I understand it, produce a relatively similar result, so the differentiation is in the implementation. The usage of one or the other may be dependent on the situation, one better for permanent installation and the other for undetermined performance spaces. I don't have enough experience to make that call. The VBAP system necessitates entering speaker position and distance from the 'listener', and so is a little more difficult in initial setup. Ambisonics, as far as I can tell, is more speaker position 'agnostic' (at least within reason) making setup much easier and allowing for a variety of performance settings. The problem with Ambisonics is that it has a much tighter 'sweet spot' (though I understand that it is getting much wider as decoding speeds up and more thorough HRTFs are implemented) and there are certain perceived phasing artifacts if the listener moves their head to quickly in the sweet spot.
There are libraries for both methods readily available for MaxMSP. On the VBAP side, the library is written by the methods inventor, Pulkki, and he has a paper on the implementation here. On the Ambisonic side, there are a few libraries out there. This page at Cycling 74 has a couple of the proven ones, including the High Order Ambisonics (HOA) library from CICM which I have used before.
I think I'm probably still going to go with my initial instinct and use Ambisonics. I would like to give a well thought out reason for this, but it's mostly based on my feeling that Ambisonics is just to cool of a psychoacoustic phenomenon not to play with. Also, the HOA library implementation is very advanced, including objects that aid in the connecting of the thousand patch lines inherent in spatialization.
The method I was planning on using is one that I have used before, but only in a binaural (headphone) implementation; that is the method known as Ambisonics. The other method is a slightly newer system called Vector Based Amplitude Panning (VBAP). They both have their strengths and weaknesses and I'll try and survey a few of them here. The VBAP system was developed by Ville Pulkki who I believe is based in Helsinki. Through my very cursory research VBAP seems like an approach based on the traditional stereo field panning concept, where the ratio of the intensity of sound coming out of two speakers gives the perception that the sound is actually somewhere in between the two speakers. VBAP is a system that allows you to extend this system out to any number of loudspeakers. Using vector based mathematics to set the relative position of the sound and the combining it in a matrix with the loudspeaker position and distances, a convincing, easy to manipulate virtual soundfield can be created. Like the stereo system, it uses ratios of intensity to position the sound, but instead of a stereo pair, it uses stereo triplets, with loudspeakers above the plane, to give elevation information. It also smooths the transference of sound from one set of triplets to the adjacent triplets in order to involve the full range of motion.
Ambisonics, on the other hand, is much less intuitive 'under the hood' but instead uses some very cool psychoacoustics that I just barely understand to achieve the spatialization effect. It's an expansion of Alan Blumlein's invention, the Mid-Side microphone technique. Instead of the VBAP technique of actual localization of the sound in a triplet of loudspeakers, the position information is encoded in and emanates from ALL of the loudspeakers through a system of phase cancellation and correlation (I think...even after reading it a hundred times it still seems like magic to me. Probably why I'm a sound lover, this stuff just fascinates me). Ambisonics necessitates encoding and decoding stages on either side of the position determination, which can be processor intensive; this is one of the reasons that 5.1 Surround has surpassed Ambisonics for surround sound in consumer electronics. Up until recently the processing power needed put the decoder price point way out of range for anyone but enthusiasts.
The two systems, as I understand it, produce a relatively similar result, so the differentiation is in the implementation. The usage of one or the other may be dependent on the situation, one better for permanent installation and the other for undetermined performance spaces. I don't have enough experience to make that call. The VBAP system necessitates entering speaker position and distance from the 'listener', and so is a little more difficult in initial setup. Ambisonics, as far as I can tell, is more speaker position 'agnostic' (at least within reason) making setup much easier and allowing for a variety of performance settings. The problem with Ambisonics is that it has a much tighter 'sweet spot' (though I understand that it is getting much wider as decoding speeds up and more thorough HRTFs are implemented) and there are certain perceived phasing artifacts if the listener moves their head to quickly in the sweet spot.
There are libraries for both methods readily available for MaxMSP. On the VBAP side, the library is written by the methods inventor, Pulkki, and he has a paper on the implementation here. On the Ambisonic side, there are a few libraries out there. This page at Cycling 74 has a couple of the proven ones, including the High Order Ambisonics (HOA) library from CICM which I have used before.
I think I'm probably still going to go with my initial instinct and use Ambisonics. I would like to give a well thought out reason for this, but it's mostly based on my feeling that Ambisonics is just to cool of a psychoacoustic phenomenon not to play with. Also, the HOA library implementation is very advanced, including objects that aid in the connecting of the thousand patch lines inherent in spatialization.
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