Caten . 2012
Kinetic sound installation

17.04.2012 > 22.04.2012 :
Eglise Saint Sauveur . Caen (FR)

Created for the Saint Sauveur chapel in Caen, Caten is a levitating sculpture, determined by gravity and guiding the evolution of a sound composition.
300 fine wires suspended from two ropes, connected themselves at each end to a slowly rotating arm, form an evanescent surface which interacts with the architecture.
By a symbolic mirror effect, the curves of the wires, created by the gravitational force, reflect the shapes of the church arches. Caten opposes the ephemeral to the eternal, the movement to the static, and produce a tension between the lightness and the millenary stability of the space.
The sound composition is inspired by the medieval solmisation prayers, especially the first verse of "Ut Queant Laxis", also known as the "hymn to St John the Baptist", used in the eleventh century to determine the names of the notes of the scale used in latin countries.
At each turn, the engines emit one of the first 4 notes of the scale (Ut, Re, Mi, Fa), creating a sequence of intervals, constantly reconfigured. Low frequencies resonate in the space and emphazise the transcendental character of a place once dedicated to faith.
The name is derived from the term catenary, which describes the plane curve formed by a rope hanging between two points.



French version :

Création originale pour la chapelle du Vieux St Sauveur, Caten est une sculpture en lévitation, déterminée par la gravité et guidant l'évolution d'une composition sonore.
300 fils suspendus à 2 cordes, elles-mêmes reliées aux extrémités à des bras en lente rotation, forment une surface évanescente qui dialogue avec l'architecture.
Par un effet de miroir symbolique, les courbes particulières des fils, créées par la force de gravitation, reflètent la forme des voûtes de l'église. Caten oppose l'éphémère à l´éternel, le mouvement à l'immuable et met en tension la légèreté avec la stabilité millénaire de l'espace.
La composition sonore est inspirée par la solmisation des prières médiévales, et notamment des premiers vers de "Ut Queant Laxis", ou hymne à St Jean-Baptiste, utilisée au XIe siècle pour constituer les noms des notes de la gamme solfégique des pays Latins.
À chaque demi-tour, les moteurs émettent une des 4 premières notes de la gamme (Ut, Re, Mi, Fa), créant ainsi une suite d'intervalles déterminés, mais constamment reconfigurés de manière aléatoire. Les basses fréquences entrent en résonance avec l'espace et réaffirment le caractère transcendantal d'un lieu autrefois consacré.
Le nom Caten est dérivé de caténaire, qui désigne la courbe plane formée par une corde pendue entre 2 points.


CREDITS

Caten was produced for the festival Interstice, with the support of the Station MIR.
www.festival-interstice.net
www.station-mir.com









©2012.David.Letellier










Versus
2011 . installation . 220 x 110 x 220 cm (each)

Versus is a sound installation consisting of two kinetic sculptures placed face to face.

Each sculpture is made out of 12 triangular panels, hinged and powered by six linear actuators, controlled by a specific program. At the center of each corolla, a loudspeaker and a microphone allow to play and record sounds.

At regular intervals, each sculpture produces a sound, simultaneously recorded and analyzed by the opposite sculpture, which then moves according to the frequencies of this sound.
Like a feedback loop, it then plays back the recorded sound, with the errors and disturbances caused by the reverberating space and the visitors.

By intervening in this conversation, the viewer becomes an actor, as he degrades the communication by his presence and the noises he produces. As the panels move back and forth at a pace determined by the environmental sound, they create a non-immediate interaction, where the imperfections of reproduction are becoming creative elements.

The original sound is continuously transformed, and becomes something entirely new and unpredictable. The memory of past events is hold for a moment, until it is reproduced, degraded, and then forgotten, replaced by the present.



CREDITS

Versus was produced with the support of the INSA foundation, Lyon.




photos.credits:
©2011.David.Letellier


photos permission requests : davidletellier@gmx.net








Tessel
2010 . installation . 400x200x300cm

A kinetic sound installation investigating the perception of sound and space.

Tessel is constituted of a suspended and articulated topography of 4 x 2 m, subdivided into forty triangles. Twelve of them are fitted with motors and eight are equipped with audio transducers, which transform the surface into a dynamic sonic space. A dialogue between space and sound is created through this sculptural "choreography". Our perception is altered, as the surface slowly modifies its shape.

From Tinguely's poetic machines to Alexander Calder's mobiles or Buckminster Fuller's synergetics, Tessel combines influences that question the link between geometry, movement and chaos, thus continuing the quest for beauty in the synesthetic perception of sound and spatial phenomenons.

Its name is derived from "tessellation", a term applied to the geometric subdivision of a surface into plane figures, also known as "tiling". It also describes a software technique that allows calculation of renderings through the subdivision of surfaces into polygons. The term has its origin in the Latin word "tessella", describing the square tiles used to make mosaics.

Tessellation has been applied throughout history from ancient to modern times, from two to n-dimensional configurations and merges science and art through mathematics. Here Tessel is based on the "pinwheel pattern", a non-periodic tiling coined by mathematicians Charles Radin and John Conway, which allows the creation of an infinitely complex geometry constructed with a simple single "seed": a right triangle. Here, the pinwheel pattern is transformed, folded and transposed to the third dimension.

CREDITS

Tessel is a collaboration between French composer and artist David Letellier, and LAb[au], Belgian electronic arts studio. Tessel is a co-production of the galleries MediaRuimte (Brussels) and Roger Tator (Lyon), realised with the financial support of Arcadi, Dicream and the Commission des Arts Numériques de la Communauté Française de Belgique.

<> photos.credits : see caption ( mouse over image )
©2010.David.Letellier
©2010.Eelco Borremans
©2010.LAb(au)


photos permission requests : dl@davidletellier.net

Technical description :
The installation is divided into two parts: an aluminium frame/case which holds all the technical gear and a folding tessellated surface.
The aluminum case counts 12 (nema 23) stepper motors fitted with spools and encoders (avago optical incremental encoders), fed by 48V DC transformers. These are controlled and watched by 3 parallax propeller microcontrollers (parallax USB proto boards), each one opening a serial port to a mini-itx atom computer fitted with an 8 channels soundcard. Firmware is written in Spin (parallax high level language) and assembly. The computer runs custom Basic/C software which takes care mainly of computing positions, adapting acceleration/deceleration ramps to morph from one position to the next and synchronizing motion with multi channel sound. There are also two Audio 700Watts 4 channels car amplifiers in there.
The surface hangs on 12 pulleys with a pre-constrained nylon 1mm cable passing thru. On 8 triangles, the 4 corner ones and 4 in the middle, there are sound transducers; these are basically speakers without the cone, transmitting vibration to the surface itself. Sound is thus produced by the vibrating metallic triangles.
These triangles are made of a sandwich of 2 Dibond sheets (a sandwich in itself with a foam core and aluminium sheets) and rubber sheet. The Dibond triangles have been laser cutted prior to assembly. The sandwich is glued with washers making contact in between the 2 Dibond sheets, through a hole cutted in the rubber. The transducers are fitted in holes to make contact with the last aluminium layer. The surface is constituted of 3 parts, embedded rivets and overlaps allowing reassembly.










Tessel études
2010 . framed folded masa paper . 22x32cm

A series of 9 folded paper studies accompanying the Tessel installation



©2010 DL

©2010 Eelco Borremans




photos permission requests : dl@davidletellier.net


Ostinato Serie
2011 . Turntables, effects, sound

Modified turntables, producing endless mechanical loops.

The sound of the turntable arm mechanism, fitted with a piezo sensor, persistently reproducing the same movement, is filtered, processed and amplified

The term Ostinato is derived from the Italian word meaning “stubborn” , also at the origin of the english word “obstinate”.
The machine keeps trying, over and over again, but gravity always wins.



Continental Edison




Technics N°1

photos permission requests : dl@davidletellier.net








Terrain
2009 . Lambda prints on dibond . 200x200cm

Owen's lake is a dry lake in the Sierra Nevada, California. It dried up after the river that fed it was diverted in the Los Angeles aqueduct at the beginning of the 20th century.The lake surface is now made of salt, clay, sand, and other minerals, shaped by the wind, and forming a strange lunar-like topography. The Terrain project aimed at remembering the water that was once there, with the help of a tesselated surface.


©2010 DL

©2010 DL

Process


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Altiz
2007 . Video installation in 5.1 sound

Multichannel audiovisual installation
premiered in 2007 at the Nanoplex,
Leicester (UK)

Based on the Peter de Jong's attractor :
xn+1 = sin(a yn) - cos(b xn)
yn+1 = sin)c xn) - cos(d yn)

Programming : Tetsu Kondo
Post-production : Eilert Janßen



The generalization of digital technologies has created a common medium : the digital material. The reduction of any data, any idea, any creation, to a series of 0 and 1, implies the theoretical disappearance of the differences in various medias coding : the same information can be indifferently translated into image, text, sound, or even movement, taste or smell.

The possibility of an art of conversion is thus rising; different senses can be solicited using mediums whose internal structure is common.

Altiz adopts this transversal approach and uses the conceptual and technological bridges that have been therefore naturally created between science, visual arts, mathematics and music.




©2010.David.Letellier



photos permission requests : dl@davidletellier.net








Racines
2008 . Ink on paper . 56x76cm





Racines 1

photos permission requests : dl@davidletellier.net








Fold
2011
(work in progress)

FOLD is a sonic, dynamic object; a folded sculpture that can shrink and expand, changing his shape and the acoustic of the space continuously, synchronised with a sound composition.

FOLD proposes a visual and aural synesthetic experiment, in which the perception of sound will be closely related to the various forms that the surface will take.

FOLD is a transformable system that refuses to be only one thing, rejecting the static to deploy itself, articulate, and create meaning through movement.



Fold

photos permission requests : davidletellier@gmx.net