Page 5 - Acoustic_Shell_Catalogue_2016

AS® ACOUSTIC SHELLS | VERSATILITY OF A SHELL AS® ACOUSTIC SHELLS

PORTABLE AND FIXED DIFFUSION ACOUSTIC SHELLS

When performing at a conventional theatre, symphonic and chamber orchestras,
as well soloists and opera singers, encounter problems related to the projection of
the sound and voice, due to the noise that is produced on the space of the stage
box and the absence of diffusion materials.
The sound that is produced by the orchestra is dispersed heterogeneously in all
directions, depending on the instruments. It needs an acoustic shell to channel it
towards the audience. In order not to lose the sound level and all the musicality of
orchestras, acoustic shells should be placed around them.
To project the sound, it is necessary to install diffusion panels shaped like a shell,
open towards the audience, in order to scatter the sound in that direction. The
Acoustic Shells can be installed hanging on the stage's ceiling and/or on the floor
around the musicians.
Following the research on acoustic panels, JOCAVI® adopted four of its models of
acoustic diffusers to create these models of AS® acoustic shells.
Spaces, like theatres and auditoriums, where classic music performances are
programmed, are usually big-volume rooms. Thus, due to the noise from the
audience and the lack of an acoustic shell, electro-acoustic equipment
(microphones, power stages and loudspeakers) is overused in these spaces.
Musicians, singers and musical directors do not tend to overuse electro-acoustics
in order not to distort the natural colour of the instruments and voices. The use of
our AS® acoustic shells increases the natural level of the sound that is genuinely
produced by the instruments and naturally increases the level of the acoustic
pressure of the room, thus leading to a balanced diffusion throughout the whole
range of the sound spectrum.

AS® ACOUSTIC SHELL® - THE BRAND

AS® Acoustic Shell® is a brand that sells highly specialised acoustic shells which
are conceived in the laboratories (R&D) of the Portuguese company JOCAVI®
Acoustic Panels Lda. The AS® brand belongs to the JOCAVI® Group. We prepare
projects to advise on our products by seeking the best shell for each space.
We sell for permanent installation in theatres and auditoriums where the main
activity requires the use of these acoustic diffusers. We also carry out the
installation and acoustic checking and enter into maintenance contracts for our
shells. We are AS® Acoustic Shell®, a company specialised in acoustic diffusion
shells.

VERSATILITY OF A SHELL

Unlike the most ancient and original open-air acoustic shells made of stone in roman
amphitheatres, today's acoustic shells used in performance rooms have to be
versatile and discreet, so that their presence does not hinder the use of the space for
the most varied types of performances.
Our shells have been developed and built with light and attractive materials, which
facilitate as much as possible their practical use. They adapt to the orchestra by
increasing the number of the necessary modules and by adjusting their application
according to the type of performance. It is a stage equipment that is easily assembled
and disassembled and that is imperceptible when it is not being used.

ACOUSTIC BEHAVIOUR

The purpose of acoustic shells is to use both the acoustic energy and sound, which
were beforehand wasted in the stage-box, and direct them towards the audience.
It is particularly important how this is done. Acoustic shells, which are simply a flat,
convex or concave piece of varnished plywood, are normally used. These pieces, due
to their big size, return the acoustic energy in very tight angles of incidence. Their
scattering coefficient versus frequency is not balanced either, meaning that they do
not scatter all frequencies in a uniform way. They scatter high frequencies much more
often than medium/low frequencies.
Effectfuser® AcSh®, Dynamicflow® AcSh®, Woodfoil® AcSh® and Plura® AcSh®
acoustic shells come from duly characterised JOCAVI®’s acoustic diffusion panels, in
order to obtain the best diffusion balance throughout the sound spectrum. Therefore,
a good and distributed angular coverage and a better balance of the diffusion values
over the several frequencies are obtained.

84