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The essence of sound: The Faï’s Horns
The Place: its human and spatial context
The Ferme du Faï, perched at 3600 ft high on the mountains overlooking the
village of Saix (Hautes-Alpes, France,) sits on a slope opposite the cliff-face. Since
1963, the place is directed by the association “Le village des Jeunes” (a delegation of
Youth Solidarity) who organizes different kinds of voluntary works from environmental
.projects to various constructions. Besides its inhabitants, since the end of the 90s, it has
also been home to three rather odd-looking « horns », actually a gigantic sound
amplification system located out in the open air.
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Why the Horns? A short genesis
In 1991, Jacques Chataignier, who was the catalyst for the construction of the
horns and was later to be their future director, noticed that the site was gifted with a
natural suitability for echoes. Intrigued, he first tested a simple amplification system: he
directed two 50W speakers normally meant for personal use at the cliff.
From this first sound experiment, the project of constructing a sound system had
its beginning, one that was capable of making the most out of the acoustic property
provided by the location’s natural placement. Since then, the Faï’s “natural organ” has
become an essential ingredient in the region’s identity and its impressive “bass’ horn”
now its central attribute.
Thanks to the constant presence of “Village des Jeunes” volunteer works, the
construction began in 1991 – after three years of various experiments carried out with
the help of pre-existing audio systems - under the supervision of Michel Stievenart, the
sound engineer, who drew the plans and oversaw the implementation of the High and
Medium frequency Horns, built during 1993.
In 1997, it was the Bass frequency Horn’s turn to see the light of day, finally
finishing the long-imagined system. The goal: to avoid sound dispersion and echo
superimposition as far as possible. Indeed, the first experimentations showed that it was
not only power, but also directionality (gradient, location, direction) of the sound that
had a crucial part to play in the final quality of the listening.
What can it be used for?
The sound made by the Horns is not meant to be listened directly, instead it is to
be listened to through its echoes (distance from horns-cliff: 2625 ft i.e. time: roughly
2s, 2 to 5 secondary echoes bouncing off the 297 acres of the cliff’s face, three main
places for listening). According to the observations made by Pierre Jacques, the acoustic
engineer, the horns are suitable for music with slow tempo (requiring long enough
intervals between transitory sounds). Therefore the music styles that are most
appropriate are listed below: movie soundtracks, operating singing, experimental
music, sound design, certain classical music pieces, etc. All the equipment needed for
live music use is also available.
Who’s who? Project’s operators
Michel Stievenart: engineer
Jacques Chataignier : manager of implementation
Village des jeunes : building
Jean-Michel Pillone : Ferme du Faï’s director, sound and lights technician
René Dupré : audiophile, renovation
Pierre Jacques: acoustician engineer, report project
Queyras Libre: 3D modelling
The final four operators have provided the following data:
The physical features of the sound system, operational since 1998
[Data from Pierre Jacque’s research report (2011) and Jean-Michel Pillone]
High frequency Horn : 4 x Rad Motor 950 PB , features below
Bandwidth: 500 Hz – 20KHz
Electrical power allowance: 100 watts RMS
Sensitivity: 111dB
Nominal impedance: 8 or 16 ohms
Medium frequency Horn : 4 x speakers RCF L12 S 110 KP
Bandwidth: 60 Hz- 2000Hz
Electrical power allowance: 500 watts RMS
Sensitivity: 101 dB
Nominal impedance: 8 ohms
Bass frequency Horn : 12 x speakers RCF L15 S800
Bandwidth: 40 Hz- 1500 Hz
Electrical power allowance: 700 watts RMS
Sensitivity: 99, 5 dB
Nominal impedance: 8 ohms
These three horns are managed from the sound control which is comprised of:
- 2 CD players (5 CDs loadable)
- a mixing table YAMAHA MX 12/4 (12 inputs, 4 bus)
- a “homemade” filter, equipped with a symmetrical input with plug XLR 3 pins and 3
symmetrical outputs with plug XLR3 pins (sound distribution in three band frequency),
and a potentiometer with an input level and a 3 positions cut frequency selector. When
using the system in the “three horns” set up, the cut medium/bass frequency control is
180Hz.
- 2 amp Chevin Research A2000 2 channels: The first amp’s channel A supplies the
High frequency horn’s 4 speakers 16ohms, connected in parallel to the amp, which
gives a global impedance of 4 ohms. In this impedance, the amp supplies 800watts
power. The first amp’s channel B supplies the Bass frequency horn’s twelve speakers,
which are connected to the amp in 4 parallel groups of 3 in series, providing a global
impedance of 2 ohms. The second amp’s two channels are reserved for the Medium
frequency horn speakers.
- A bass frequency signals generator, brand Centrad GF 763AF. Can be used to carry
out either potential tests or calibrations.
H.freq Horn-2012 M. and H.freq. Horns after renovation-2013
Outlook from the B.freq. Horn- 2012
Created by Agnès André/Joon Kim