IN SITU: Sonic Greenhouse
“IN SITU: Sonic Greenhouse” is a large-scale audio-architectural installation which took place in September-October 2016 at the historical Winter Garden Greenhouse in Helsinki, Finland, and was experienced by approximately six thousand visitors. The piece transformed the entire glass structure of the greenhouse into a multichannel sounding object, or a macroscale musical instrument.
Seventy structure-borne sound drivers – or vibration speakers – were used to transfer audio vibrations into the building’s glass panels, transforming them into loudspeakers. The idea is to drive sound all over the greenhouse’s structure, creating an immersive “sound-dome” where unique aural impressions can be designed via custom spatialisation software.
The work brings together an original combination of sound and architecture with the larger issues related to the “greenhouse”-concept, such as environmental issues and the poetics of connection/separation inherent to a glass structure. The greenhouse metaphor was developed in the compositional and spatialisation strategies involved in the piece, as well as in the establishment of a weather data stream into the installation’s generative sound engine. Sonic Greenhouse was a collaborative work by two composers of electronic music. The process was completed in parallel and in dialogue, with no specific personal tasks assigned. The resulting piece can be considered to be a duo. Greenhouse stems from pioneering research conducted by Lähdeoja and Moreno on situated sonic arts using structure-borne sound, both of whom are artist-researchers specialised in alternative and custom sound technologies.
Design and Implementation
The Helsinki Winter Garden comprises three different spaces: a) the central Palm Room (surface 280m2), b) the eastern wing’s Cactus Room (200m2) and c) the western wing’s social space (170m2). “Sonic Greenhouse” was designed in intimate connection to the given space in order to foster integration into the physical structures, plan and human life, acoustics and poetics of the space. A prior period of sensorial research was completed by multiple visits to the site spanning over a year, observing how the staff and visitors behave in the space and how the building reacts to different weather conditions.
The Palm Room (a) acoustics are very reverberant, cathedral-like and the space is filled with luxuriant vegetation. The sound work was designed to respond to this grandeur with full-spectrum and dynamic sonic constructions involving precisely rendered movements of sound within the glass structure. The Cactus Room (b) is very silent and intimate. In accordance, the sound was designed to occupy the space with precise, intricate sounds which draw the visitor’s attention to details and silent contemplation. The social space (c) was left as a relaxation space, convenient for discussion and studying documentation about the work presented in printed format.
The Sonic Greenhouse implemented a sound diffusion system in two of the Winter Garden’s three rooms. A 50- channel system was built in the Palm Room and another, independent system with 20 channels was built in the Cactus Room. Two different types of audio transducers were used: structure-borne sound drivers attached on the building’s glass walls and on custom-made suspended plexiglass panels, and small cone loudspeakers enclosed in glass jars placed on the ground amidst the vegetation. Sound diffusion via structure-borne sound drivers was an aesthetic starting point for the entire piece. These drivers enable to transform a rigid surface into a full- range speaker with minimum visual impact. The driver and glass panel combination is acoustically ideal for creating a large-scale sound-scape – oriented aural impressions. The panels act as flat panel dipole speakers, providing a larger and more diffuse acoustic image than a more directive cone speaker. In this sense, diffuse sound emanating from glass panels creates an aesthetic unity: the sound source is not easily located, and perceptually it blends into the glass, its transparency and the surrounding landscape. The cone loudspeakers were designed to provide a spatial counterpoint to the wall and ceiling transducers, as well as to create a symbolic visual element – a speaker enclosed in glass replicates the greenhouse idea in miniature scale. In a sense the speaker jars work as a metaphor of the whole installation.
Weather Data-Driven Sound Engine
The installation’s both sound engines and source audio material were controlled by real-time weather data retrieved from the openweather internet service. Wind velocity, temperature, pressure, and humidity data were mapped both to macro-scale events such as sound selection and mixing and to microsound-level operations like grain density and spectrum. The motivation for connecting the Cactus Room’s internal “sound life” to the external weather conditions stemmed from the poetics of transparency and frontier of a greenhouse. Within the glass frame one can visually observe outside events, but has a very limited perceptual access to the elements. By connecting the outside conditions to the sound engine, we envisioned to find a way around the greenhouse’s “boundary condition”. As a result, we obtained a perpetually varying generative sound structure tightly related to the atmosphere inside as well as outside the greenhouse.
The Sonic Greenhouse project is a unique sound art piece by its original concept, its architectural nature and its dimensions. To the best of our knowledge, it constitutes the Finnish premiere for a whole building being transformed into a musical instrument. The piece received approximately 6000 visitors, and the project to attained considerable media attention and press coverage. The work constitutes a pioneering example of interdisciplinary research combining art, science and technology as it involved innovations in the fields of sound diffusion technology, acoustics and sound art practice. Overall, the piece’s rationale was to foster social awareness on one of the key contemporary issues of the anthropocene – the redefined relationship between the dominating human and the contained nature. Through the sonic medium, the piece aimed to lead the public into a sensorial inquiry about the present-day dialectics/dialogue between man and nature.
Venue and Contact Information
Talvipuutarha / Winter Garden, Hammarskjöldintie 1, Helsinki
Open to the public 22.9.-6.10.2016:
For further information or print quality images of the project, please contact producer Kati Åberg:
sonicgreenhouse2016 [at] gmail.com