Download Playpens, Fireflies and Squeezables: New Musical Instruments

Playpens, Fireflies and Squeezables: New Musical
Instruments for Bridging the Thoughtful and the Joyful
Gil Weinberg
Final Draft – will be published in Leonardo Music Journal December 2002
ABSTRACT
The author discusses research in music cognition and education
indicating that novices and untrained students perceive and learn music
in a fundamentally different manner than do expert musicians. Based on
these studies, he suggests implementing high-level musical percepts and
constructionist learning schemes in new expressive musical instruments
that would provide thoughtful and joyful musical activities for novices
and experts alike. The author describes several instruments---the
Musical Playpen, Fireflies and Squeezables---that he has developed in
an effort to provide novices with access to rich and meaningful musical
experiences and recounts observations and interviews of subjects
playing these instruments.
Gil Weinberg is a doctoral candidate in the Hyperinstrument group at
the Massachusetts Institute of Technology Media Laboratory. He holds an
undergraduate degree from Tel Aviv University in music and computer
science and a graduate degree in media arts and sciences from MIT. His
work, which was recently featured in Ars Electronica, focuses on
designing and building networked musical instruments for novices and
experts. Weinberg's latest composition, Nerve, premiered in February
2002 with the Deutsches Symphonie-Orchester Berlin.
Gil Weinberg (composer, researcher), MIT Media Laboratory, 20 Ames
Street E15-445, Cambridge, MA 02139, U.S.A. E-Mail:
<[email protected]>.
1
The 20th century saw the diffusion of a number of powerful musical
ideas from the "high-art" academic world into popular music. Varèse’s
exploration of timbre, Reich’s minimalism and Cage’s happenings are
some
examples
of
pioneering
20th-century
high-art
musical
experimentations that were diffused into the wider world and
contributed to the formation of popular electronic music as we know it
today. Musicians such as Frank Zappa, Philip Glass and Michael Nyman
brought ideas and trends from both worlds into their music. At the same
time, technical innovations such as FM synthesis grew from laboratory
experiments into commercial products, providing novices with the power
to create and manipulate sounds in a manner that had previously been
accessible only to a small group of experts. These recent cases, as
well as such earlier examples as the popular reach of opera in the 17th
and 18th centuries, contradict the notion of an inherent separation
between what is usually considered popular music for the masses and
what many regard as serious or high-art music for the elite. There are
no intrinsic reasons why rich and thoughtful “high-art” musical ideas
and experiences should not be available to and enjoyed by novices and
the general public, nor why the unique expressive and emotional quality
that is usually affiliated with popular music should not be part of the
high-art experience. However, when investigating fields such as music
perception and music education, we do find strong evidence that novices
and experts perceive and relate to music differently [1] and that
beginners learn music in a fundamentally different manner than do
advanced students [2]. Other studies suggest that this differentiation
also
bears
social
implications,
stressing
that
the
remarkable
proliferation in the consumption of popular music in everyday life
tends to manifest itself as incidental listening, passive participation
and utilitarian consumption, such as music in shopping malls or
aerobics classes [3]. These experiences, while they expose more people
to more music for longer periods of time, tend to lack the rich and
thoughtful aspects of concentrated listening and active creation of
music.
Fields of Study
In an effort to combine thoughtfulness and expression in musical
experiences that are accessible to all, I have investigated research in
cognition and perception, music education and instrument interaction,
which I believe can provide several possible directions for bridging
these different modes of perception and learning.
Cognition and Perception
David Smith has presented a number of studies that show how a
significant number of musical percepts, which are regarded as
fundamental and obvious by expert musicians, are not perceived as such
by novices [4]. For example, he shows that novices cannot perceive
octave equivalence; they do not identify or categorize intervals,
diatonic hierarchy or transposition, and do not follow structure and
shape in the same way that experts do. Smith and Marla also conducted a
quantitative study showing that while experts’ aesthetics focus on
syntactic musical aspects, novices’ aesthetics stem much more from
referential,
sensual
and
emotional
sources
[5].
These
studies
encouraged me to explore what I regard as high-level musical percepts--composite musical elements such as stability, contour or tension--that have been proved to be perceived and understood by novices, but
2
that also bear a rich analytical core, which can intrigue the
experienced musician. For example, various psychoacoustics studies show
the perceptual significance of the general outline of a melody’s pitch
curve, also known as melodic contour [6]. In one case, it was shown
that novices were able to retain the contour of a semi-known melody
much more easily than its specific pitches [7]. Trehub et al.
demonstrated that melodic contour can be perceived by infants as young
as 1 year old, strengthening the inference that this percept is well
ingrained in human cognition [8]. These studies suggest that by
providing an intuitive introduction to the playing and manipulation of
contour, we can create a bridge between the expressive manner in which
novices relate to melodic curves and the analytical manner in which
experts perceive the lower-level relationships between pitches and
intervals. I believe that providing novices with the power to create
and phrase a melody by manipulating its contour, regardless of its
exact pitches and intervals, offers them a unique creative experience
that is usually reserved for experts and that can serve as an entry
point for further investigations into more advanced concepts such as
harmony and counterpoint. Another example of a high-level musical
percept that can serve as an intuitive and expressive bridge for deeper
musical investigations is stability. It has been shown, for example,
that the cognitive perception of structural stability is influenced by
musical parameters such as tempo, pitch commonality, dissonance and
rhythmic variation [9]. Here too, an algorithm that would allow players
to manipulate these parameters (and therefore control stability) can
provide a unique expressive experience that could lead to deeper
musical analyses. Similarly, an algorithmic implementation of the highlevel percept of harmonic tension, based on Lerdahl’s tonal tension
theory [10], can lead to a more detailed and analytical comprehension
of harmony.
Music Education
With many musical education systems, such as Dalcroze [11], OrffSchulwerk [12] and Suzuki [13], educators find it difficult to combine
theory and technique with the expressive and emotional aspects of
playing and creating music. Jeanne Bamberger addresses this difficulty,
asserting that separating the formal from the expressive might alienate
children from music making altogether [14]. Bamberger shows that
preteens are inclined to process music in a “figural” manner, in which
they tend to focus on “know-how”---intuitive aspects such as the global
features of melodic fragments, the “felt” features of contour, rhythm
and grouping, etc. Most education programs, however, require children
in their early teens to process music in what Bamberger defines as the
formal mode, in which musical notation, theory and analysis are
abruptly introduced. As a result of this “know-that” approach certain
important musical aspects that came naturally in the figural mode may
be hidden, at least temporarily, when children try to superimpose
formal knowledge upon figural intuitions. If this “crisis” is not
acknowledged and the gap between the different modes is not negotiated,
it can lead players to give up music altogether [15]. My approach for
addressing
this
conflict
is
informed
by
Seymour
Papert’s
Constructionist Learning theory---an educational philosophy based on
the notion that learning is most effective when the student constructs
personally meaningful artifacts. The theory states that intuitive and
emotional connections with personally created artifacts, students can
construct their knowledge and obtain powerful theoretical ideas. Papert
3
emphasizes the ability of the computer to provide such personal and
meaningful learning experience to a wide variety of learners. "Because
it (the computer) can take on a thousand forms and can serve a thousand
functions, it can appeal to a thousand tastes" [16].
Instrument Interaction
I believe that children, novices and diverse audiences can gain access
to rich and insightful musical phenomena through active participation
in creating music. But in order to allow such access without
compromising the figural intuitions, educators should focus on
designing and building new musical instruments that can serve as
expressive and enjoyable gates to deeper musical experiences. It is
well known that children construct an important part of their knowledge
about the world by interacting with instruments and physical objects of
various kinds. Piaget, for example, showed the critical role of
interaction with tangible objects in the development of human
cognition. He demonstrated how processes such as the development of
spatial locomotion, definition of the self, and abstract representation
are connected to and enhanced by interacting with physical objects
[17]. Various researchers at the Massachusetts Institute of Technology
(MIT) Media Laboratory have built on these findings by exploring the
cognitive effects of interacting with electronically and digitally
enhanced physical objects. Papert focused on the idea that learning can
be enriched by embedding technology in objects and allowing children to
interact with the objects’ behavior, not only with their physicality
[18]. Mitchel Resnick et al. concentrated on designing programmable
digital toys that treated the players as collaborators in the design
process and not just as “users” [19].
Tod Machover brought similar
ideas to the musical realm by initiating the Hyperinstruments project.
The project’s preliminary goal was to build “digitally expanded musical
instruments in an effort to provide extra power and finesse to
virtuosic performers” [20]. It was expanded later to the design of
interactive
musical
instruments
for
non-professional
musicians,
students,
music
lovers
and
the
general
public
[21].
Current
Hyperinstrument research is attempting to push the envelope in both
these directions by designing high-level professional systems that
measure subtle and sophisticated human performance and by building
interactive entertainment systems for novices and the general public.
Instruments and Applications
Based on the research in these fields of study, I have formulated a
hypothesis suggesting that by embedding high-level percepts and
constructionist learning schemes in intuitive and compelling musical
instruments
we
can
provide
expressive
and
pleasurable
musical
experiences to children, novices and the general public without
compromising richness, thoughtfulness and artistic depth. In order to
address this hypothesis, I have developed three kinds of musical
instruments---the Musical Playpen, Fireflies and Squeezables---in which
I
embedded
algorithms
for
high-level
musical
control
and
constructionist learning in an effort to highlight the intuitive and
expressive nature of some thoughtful musical experiences.
4
The Musical Playpen
The
Musical
Playpen
was
the
framework
for
my
preliminary
experimentations with designing and evaluating algorithms for highlevel musical control [22]. I chose to design the instrument for
toddlers and infants, so that I could investigate whether children that
young can participate in a meaningful, active musical experience. I
began by installing two high-level controllers, one for contour and the
other for rhythmic stability, in an environment that the subjects would
find familiar and fun regardless of any musical functionality---a 1.5x-1.5-m playpen filled with about 400 colorful plastic balls. This
particular musical playpen, however, did offer musical responses in
correlation to children’s activity in the space. Players’ movements
around the playpen propagated from ball to ball and triggered four
piezo-electric accelerometers that were hidden inside four selected
balls in each corner of the playpen. The balls’ ability to transmit
hits to neighboring balls, combined with the accelerometers’ high
sensitivity, allowed for almost any delicate movement around the
playpen to be captured by at least one sensor. The analog signal was
then digitized and sent to a Macintosh computer running Max [23], where
it was mapped to musical output played from speakers below the playpen
(Fig. 1).
I mapped two of the four corners to control the musical contour of
an Indian raga, so that the more energetic the players’ movements in
these corners were, the higher the Indian raga pitches became. Children
could therefore create melodic phrases and manipulate their curves by
changing the intensity of their body movements in these corners.
Player’s movements in the other two corners were mapped to an algorithm
that controlled the tempo, rhythmic variation, and timbre of percussive
sequences in an effort to provide access to controlling rhythmic
stability. The more energetic the players were when near these corners,
the higher the probability was for eighth notes, triplets, sixteenths
and quintuplets to be added to the well-ordered quarter notes of the
default pattern. The tempo curve also fluctuated more sharply (between
100 and 180 beats per minute), as did the rate of timbral change (the
sounds used included those of bass drums, tablas, snares, and cymbals
of various kinds).
The observation sessions conducted with the playpen at MIT and at
the Boston Children’s Museum from 1998 to 1999 produced a wide range of
responses to the new instrument and the high-level musical control that
it offered. For example, a 1-year-old infant started her session by
triggering a sequence of notes as she was placed near one of the
Indian-raga corners. The infant looked in the direction of the sound
source and tried to move her hand towards that corner, seemingly trying
to repeat the music she heard. When she succeeded and another melodic
phrase was played, she smiled, took one ball and tried to shake it,
obviously without audible results. Frustrated, she then threw the ball
towards a rhythmic corner, generating a short percussive sequence. She
approached this corner while moving her torso back and forth, laughing
when discovering that her movements controlled the music. After
stopping for a while, as if considering her next move, the infant
started to slowly move her body again back and forth, gradually
accelerating her movements, generating less and less stable percussive
sequences. Only after repeating this behavior in another corner did the
infant seem to be ready to use more expressive, less restricted
gestures all over the playpen.
5
This constructive, almost analytical approach did not repeat itself
with another 16-month-old toddler. The first play patterns that he
demonstrated were turbulent movements all over the playpen, kicking and
waving his arms, throwing balls all over and accompanying himself by
singing and screaming joyfully. After this expressive explosion, the
toddler gradually started to explore the different responses in the
different corners around the playpen. He then performed several abrupt
jumps from one corner to another. Towards the end of the observation,
the toddler seemed to have developed a unique play pattern: His
“compositions” included ecstatic random parts in the center of the
playpen, which were interrupted by gentle exploratory parts near the
corners (Fig. 2). In a environment, where he was placed in a playpen
that was disconnected from its musical output, no organized play
patterns were observed [24].
It can be seen then that for the infant, the controlled and
restrained exploration led to more impulsive and joyful play, while for
the toddler it worked the other way around---the spontaneous explosion
led to more thoughtful and structured behavior. These responses
strengthened my belief that with the right instruments and controls,
young children can have access both to spontaneous, expressive musicmaking as well as to more serious and thoughtful musical explorations.
The findings also encouraged me to develop a new set of instruments,
which I entitled “Musical Fireflies”, in an effort to address older
children and novices who are more cognitively developed and can discuss
their impression of the experience.
Musical Fireflies
The Musical Fireflies [25] are palm-sized digital musical instruments,
designed to introduce users to mathematical music concepts such as
beat, rhythm and polyrhythm without requiring any prior knowledge of
music theory or instruction. They were designed to provide a
constructionist musical experience that would bridge between the
figural and the formal learning modes, by offering players expressive
and fun rhythmical experiences that can be easily transformed into
analytical and formal exploration. The Fireflies allow players to
construct their own rhythmic patterns, embellish the patterns in real
time, synchronize patterns among different players and trade instrument
sounds with their peers. For a single player, the instrument provide
figural and formal familiarization with musical concepts such as
accents,
beats,
rhythmic
motifs
and
timbre.
The
multi-player
interaction introduce players to more advanced musical concepts such as
polyrhythm [26].
Each Firefly has two input buttons connected to a "Cricket" [27]---a
Logo-programmable microprocessor responsible for processing, mapping,
and communication. Using these buttons, players can enter rhythmic
patterns that the microprocessor convert to Cricket Logo general MIDI
commands and send through a serial bus port to a “MidiBoat” [28]---a
small General MIDI circuit that is connected to a top-mounted speaker.
All the electronic components are embedded in the Firefly’s 20-x-14-x2.5cm 3D-printed case (Fig. 3). Interaction with the Musical Fireflies
occurs in two distinct modes–--the Single Player mode, in which players
convert numerical patterns into rhythmical patterns, and the Multi
Player mode, where collaboration with other players enhance the basic
patterns into polyrhythmic group compositions. In the Single Player
mode, tapping the left and right buttons records accented and non6
accented notes respectively. After two seconds of inactivity, the
Firefly plays back the entered pattern in a loop using a default tempo.
This activity provides players with a tangible interface for entering
and listening to the rhythmical output of any numerical pattern they
envision. For example, the numerical pattern 4 3 5 2 2 would be entered
and played back as follows:
x y y y x y y x y y y y x y x y (loop)
x = Accented note played by the left button. y = Non-accented note
played by the right button.)
During playback players can input a second layer of accented and nonaccented notes in real time, using a different timbre. Each tap on a
button plays a note aloud and recorded its quantified position so that
the note becomes part of the rhythmic loop. When two playing Fireflies
"see" each other (i.e. when their infrared signals are exchanged) they
automatically
synchronize
their
rhythmic
patterns
(a
similar
interaction occurs when real fireflies synchronize their light pulses
to communicate in the dark). This activity provides participants with a
richer rhythmical composition and allows for an informal introduction
to polyrhythm. For example, if one Firefly play[s] a 7-beat pattern (x
y y y x y y) and another plays a 4-beat pattern (x y y y), then the
players can hear the process of divergence and convergence as the
patterns go in and out of phase every 28 beats, the smallest common
denominator (Table 1).
While two Fireflies are synchronized, players can also initiate a
"Timbre Trade," in which instrument sounds are traded between the
devices (Fig. 4). Pressing either the left or right button trades both
layers of the accented or non-accented timbre respectively. This allows
for a higher level of musical abstraction, because the rhythmical
patterns become separated from the specific timbre in which they were
created. Because the interaction becomes richer as each Firefly gains
more timbres, the system encourages collaborative play as participants
become motivated to trade and collect timbres from their peers.
Observations of play sessions with the Musical Fireflies during the
year 2000 were followed by discussions with the players. Participants
were asked about the expressive and educational aspects of the session
as well as their suggestions for improvements. A Max-based software
version of the application was prepared so that players would be able
to compare the software version with the tangible interaction that they
had with the physical Fireflies. Both novices and experienced players
found the concrete aspects of playing with a physical object more
compelling than the computer-based graphical user interface, mentioning
that the unmediated connection with the instrument contributed to the
feeling of personal connection to the music they created. Experts
seemed to be most intrigued by the construction of group polyrhythmic
compositions. Most novices, however, found it a bit confusing,
suggesting that there should be a more moderate learning curve between
single and multi-player modes. Other weaknesses mentioned were the lack
of variety in rhythmic values and rests, the lack of continuous
development of the recorded patterns and the inability to play in
larger groups. These weaknesses are currently being addressed in the
“Beatbug Network” project (See “Future Work” section below).
7
Squeezables
In the Squeezables project [29], I attempted to combine all three
aspects
of
my
hypothesis---high-level
musical
controllers,
constructionist interaction and a musical instrument that could provide
expressive and intuitive control---into a complete artistic experience
that would culminate in the performance of a musical composition. My
goal was to allow a group of players, consisting of novices and
experts, to interdependently collaborate in constructing a meaningful
musical composition. The instrument, therefore, was made of six
squeezable and retractable gel balls mounted on a small podium (Fig.
5), which Players could simultaneously squeeze and pull to manipulate a
set of low- and high-level musical percepts. The combination of pulling
and squeezing allowed players to utilize familiar and expressive
gestures and to control multiple synchronous and continuous musical
channels. Several materials were tested as means of such soft and
expressive control. For the final prototype, I chose soft gel balls,
which proved to be robust and responsive, providing a sense of force
feedback control that derived from the elastic qualities of the gel.
Buried inside each ball was a 0.5-x-2.0-cm plastic block covered with
five pressure sensors that were protected from the gel by an elastic
membrane. The analog pressure values from these sensors were
transmitted to a digitizer and converted to MIDI. The pulling gestures
were sensed by six variable resistors that were installed under the
table. An elastic band connected to each ball added opposing force to
the pulling gesture and helped to retract the ball back onto the
tabletop (Fig. [6]).
In order to better evaluate the high-level algorithms in the
instrument, I decided to implement some straightforward mappings that
controlled relatively low-level musical parameters. For example, one of
the balls formed a one-to-one connection between squeezing and pulling
to the modulation rate and range of two low-frequency oscillators,
respectively. For other balls I developed higher-level algorithms to
control percepts such as contour and stability. Based on Dibben’s
findings, I mapped the gestures of pulling and squeezing of the
“Arpeggiator” ball to control a combination of musical parameters, such
as tempo, pitch commonality, dissonance and rhythmic variation, so that
the more the ball was squeezed and pulled, the more unstable the
arpeggiated
sequence
became.
In
order
to
provide
a
coherent
constructionist
interaction,
I
divided
the
balls
into
five
accompaniment balls and one melody soloist. The five accompaniment
balls were fully autonomous---no input from other balls influenced
their output. However, these balls’ output not only was mapped to the
accompaniment parameters but also significantly influenced the “melody”
ball. While pulling the melody ball manipulated its own contour so that
the higher it was pulled, the higher the melody pitches became, the
actual pitches, as well as the MIDI velocity, duration and pan values,
were determined by the level of pulling and squeezing of the
accompaniment balls. This allowed the accompaniment balls to “shape”
the character of the melody while maintaining a comprehensive scheme of
interaction among themselves, leading to a real-time collaborative
constructionist effort by all.
I composed a short piece for three Squeezables players, which is
based on the tension between the accompaniment balls and the melody
ball that is shaped by them [30]. The piece, which was featured in Ars
Electronica 2000, starts with a high-level of instability and builds
gradually towards a repetitive rhythmic peak. Special notation was
8
created for the piece. Two continuous graphs were assigned for each one
of the six balls. One graph indicated the level of squeezing over time
and the other indicated the level of pulling (Fig. [7]).
The process of writing and performing the piece (See Fig. [8])
served as a useful tool for evaluating the mapping and sensing
techniques that were used. In addition, I held discussions with novices
and professionals after they played with the instrument. In general,
children and novices were more inclined to prefer playing the balls
that provided high-level control such as contour and stability. They
often stated that these balls allowed them to be more expressive and
less analytical. Musicians, on the other hand, often found the highlevel control somewhat frustrating, because it did not provide them
with direct and precise access to specific desired parameters. Some
experts complained that their personal interpretation of the high-level
controllers for stability differed from the one that I implemented in
designing the instrument. Both novices and professional players found
the multiple-channel synchronous control expressive and challenging and
the pulling and squeezing gestures comfortable and intuitive. These
gestures allowed delicate and easily learned control of many
simultaneous parameters, which was especially compelling for children
and novices. The organic and responsive nature of the balls was one of
the features mentioned as contributing to this expressive experience.
When asked about the interdependent constructionist activity, one
melody ball player described her experience as a constant state of
trying to expect the unexpected.
To another player, the experience
felt almost like controlling an entity with a life of its own. Playing
the accompaniment balls led to different responses. In doing so,
players could control and manipulate the melody without being
significantly influenced themselves. However, full constructionist
collaboration with the other accompaniment players was essential for
substantially affecting the melody. In a manner similar to chamber
music group interaction, body and facial gestures served an important
role
in
coordinating
the
accompaniment
players'
gestures
and
establishing an effective outcome. Such collaborations turned out to be
especially compelling for children, who found the accompaniment balls
conducive to social interaction, intuitive and easy to play with. Some
complaints were made, however, regarding the difficulty for a specific
player to significantly influence the melody without trying to
coordinate such an action with the other accompanying players. Some
players felt that this interaction prevented them from expressing their
individual voices.
Future Work
The observations and interviews that I conducted were helpful in
evaluating certain aspects of my hypothesis, such as whether a
particular high-level controller proved to be effective, whether
players learned an advanced musical concept that would have been
inaccessible to them otherwise, or whether a specific gesture or
material proved to be expressive and intuitive. Further cognitive and
educational studies will be required in order to investigate
psychological aspects such as the experience of pleasure, and the longterm transferability of the learned musical material. I plan to conduct
such studies with a set of newly developed instruments called Beatbugs
(Fig. [9]). The Beatbugs allow for a group of eight players to create,
develop, and share rhythmic motifs through a simple interface [31]. I
composed a piece for eight Beatbug players, entitled Nerve, for Tod
9
Machover's Toy Symphony [32], which was performed during 2002 with the
Deutsches Symphonie-Orchester Berlin, [the Irish National Symphony
Orchestra and the BBC Scottish Symphony Orchestra (Fig. 10)]. Week-long
workshops that address educational and cognitive aspects were held
before each concert with groups of local children, educators and
professional musicians. I intend to publish an overview of these
workshops and concerts in the future.
10
References
1.J.D. Smith, “Conflicting Aesthetic Ideals
Music Perception <B>4<D> (1987) pp. 373--392.
in
a
Musical
Culture,”
2. J. Bamberger, "Intuitive and Formal Musical Knowing: Parables of
Cognitive Dissonance," In S.S. Madeja (ed.), The arts, cognition and
basic skills (St. Louis: Cemrel Inc., 1978) pp. 173—213.
3. T. DeNora, Music in Everyday Life (Cambridge, U.K.: Cambridge Univ.
Press, 2000).
4. D.J. Smith, “The Place of Musical Novices in Music Science,” Music
Perception <B>14<D>, No. 3, 227--262 (1997).
5. D.J. Smith and R. Marla, “Aesthetic Preference and
Prototypicality in Music: ‘Tis the Gift to Be Simple,”
<B>34<D> (1990) pp. 279--298.
Syntactic
Cognition
6. M.A. Schmuckler, “Testing Models of Melodic Contour Similarity,”
Music Perception <B>16<D>, No. 3, 295--326 (1999).
7. J. Sloboda, The Musical Mind: The Cognitive Psychology of Music
(Oxford, U.K.: Clarendon Press, 1987).
8. S.E. Trehub, D. Bull and L.A. Thorpe, “Infants' Perception of
Melodies: The Role of Melodic Contour,” Child Development <B>55<D>
(1984) pp. 821--830.
9. N. Dibben, “The Perception of Structural Stability in Atonal Music:
The Influence of Salience, Stability, Horizontal Motion, Pitch
Commonality, and Dissonance,” Music Perception <B>16<D>, No. 3, 265-294 (1999).
10. F. Lerdahl, “Calculating Tonal Tension,” Music Perception <B>13<D>,
No. 3, 319--363 (1996).
11. Dalcroze Society of America web site, <http://www.dalcrozeusa.org>
(2001).
12.
B.
Warner,
Orff-Schulwerk:
Applications
(ENGLEWOOD CLIFFS NJ: Prentice-Hall, 1991).
for
the
Classroom
13. S. Suzuki, Nurtured by Love (New York: Exposition Press, 1969).
14. J. Bamberger, “Growing up Prodigies: The Mid-Life Crisis,” New
Directions for Child Development <B>17<D> (1982) pp. 61--78.
15. H. Gardner, Frames of Mind (New York: Basic Books, 1983) pp. 110-112.
16. S. Papert, Mindstorm (New York: Basic Books, 1980).
17. J. Piaget, The Principles of Genetic Epistemology (New York: Basic
Books, 1972)
11
18. S. Papert, The Children's Machine: Rethinking Schools in the Age of
the Computer (New York: Basic Books, 1993).
19. M. Resnick, F. Martin, R. Sargent and B. Silverman, “Programmable
Bricks: Toys to Think With,” IBM Systems Journal <B>35<D>, Nos. 3--4,
443--452 (1996).
20. T. Machover, "Hyperinstruments: A Progress Report," (1992) p. 3.
Available from the Media Laboratory of the Massachusetts Institute of
Technology Unpublished.
21.
T.
Machover,
the
Brain
<http://brainop.media.mit.edu> (2000).
Opera
web
site,
22. G. Weinberg, "The Musical Playpen: An Immersive Digital Musical
Instrument," Personal Technologies Vol. 3, No. 3, 132--136 (1999).
23. M. Puckette, "The Patcher," Proceedings of International Computer
Music Association (San Francisco, CA: PUBLISHER?, 1988) pp. 420--429.
See also – http://www.cycling74.com/products/max.html
24. View a video clip of children playing the
<http://www.media.mit.edu/~gili/playpenclip.mov>.
Musical
Playpen
at
25. G. Weinberg, T. Lackner and J. Jay, “The Musical Fireflies--Learning About Mathematical Patterns in Music through Expression and
Play,” Proceedings of XII Colloquium on Musical Informatics 2000
(A'quila, Italy: Instituto Gramma, 2000).
26. S. Handel, “Using Polyrhythms to Study Rhythm,” Music Perception
<B>11<D>, No. 4, 465--484 (1984).
27. F. Martin, B. Mikhak and B. Silverman, “Metacrickets---A Designer’s
Kit for Making Computational Devices,” IBM System Journal <B>39<D>,
Nos. 3--4, 795--815 (2000).
28.
J.
Smith,
The
MiniMidi
<http://www.media.mit.edu/~jrs/minimidi> (1998).
web
site,
29. G. Weinberg and S. Gan, “The Squeezables: Toward an Expressive and
Interdependent Multi-player Musical Instrument,” Computer Music Journal
<B>25<D>, No. 2, 37--45 (2001).
30.
Listen
to
the
Squeezables
performance
<http://www.media.mit.edu/~gili/publications/Squeezadelic.mp3>.
at
31. G. Weinberg, R. Aimi and K. Jennings, "The Beatbug Network---A
Rhythmic System for Interdependent Group Collaboration," Proceedings of
NIME 2002 (Limeric Ireland: University Of Limeric, Department of
Computer Science and Information Systems, 2002).
32.
T.
Machover,
the
Toy
<http://www.toysymphony.org>.
Manuscript received 28 December 2001.
Symphony
web
site,
12
Figure Captions
Fig. 1. The Musical Playpen system. Signals from four piezo-electric
sensors in four selected balls are digitized and sent to a computer to
[activate] algorithms for melodic contour and rhythmic stability. MIDI
commands from the computer are sent to a synthesizer that plays through
four speakers under the playpen. (<c> Gil Weinberg)
Fig. 2. A toddler playing the Musical Playpen. (Photo: Gil Weinberg)
Fig. 3. The Musical Fireflies' electronics. Signals from two buttons
are sent to the "Cricket" microprocessor within, which maps them to
MIDI commands and sends them to a "MidiBoat” general MIDI unit. Audio
from the MidiBoat is sent through an amplifier to an embedded speaker.
(Photo: Gil Weinberg)
Fig. 4. Two players synchronize their patterns and trade
through the Fireflies' infra-red port. (Photo: Gil Weinberg)
Fig. 5. The Squeezables: Six squeezable
mounted on a podium. (Photo: Gil Weinberg)
and
retractable
timbres
gel
balls
Fig. 6. Playing the Squeezables: A combination of squeezing and pulling
gestures by all players. (Photo: Gil Weinberg)
Fig. 7. The Squeezables composition notation: Twelve separate graphs
indicate the level of pulling and squeezing of each ball. (<c> Gil
Weinberg)
Fig. 8. A Squeezable performance. (Photo: Gil Weinberg)
Fig. 9. The Beatbugs: A velocity
two bend-sensor antennae allow
continuously manipulating their
connected to a central computer
their rhythmic motifs with their
composition. (<c> Gil Weinberg)
sensitive piezo-electric trigger and
for entering rhythmic motifs and
pitch, timbre and rhythm. When
system 8 Beatbug players can share
peers and develop them into a full
Fig. 10. “Nerve” for an interconnected network of Beatbugs, as
performed with the BBC Scottish Symphony Orchestra. Glasgow June 2002.]
(Photo: [Tod Machover])
Table 1. An
Fireflies
example
for
a
polyrhythmic
exercise
with
the
Musical
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
7/ x y y y x y y x y y y x y y x y y y x y y x y y y x y y
4
4/ x y y y x y y y x y y y x y y y x y y y x y y y x y y y
4
A 7 beat pattern and a 4 beat pattern (played by two synchronized
Fireflies respectively) diverge and converge every 28 beats.
13