Four Seasons Centre for the Performing Arts, Toronto,
Canadian Opera Company
In June 2006 The Canadian Opera Company opened its new 2000-seat opera house in downtown Toronto. After test concerts in April and a series of opening concerts in June, the opera seasons will begin in September 2006 with a production of Wagner’s Ring Cycle.
the challenge
The new opera theatre for the COC has been more than 30 years in the making; though when funding was finally in place to move ahead and Sound Space Design was asked to join the team, there was a relatively small time window before starting 
construction. As Bob Essert first worked for the COC on an earlier aborted project in 1987-90 when he was with Artec, he was quite familiar with the needs of the COC. This, plus previous working relationships with others on the design team, allowed a quick start and close collaboration enabling
construction to begin in under one year.
the auditorium
In opera, clarity of text and natural vocal tone are important, but so are
warmth and resonance of the orchestral sound. Singers should be able to “float”
their voices, feeling the room as an instrument, while the orchestra musicians
in the pit should be able to hear each other well so they can play together in
tight ensemble. 
We
agreed that there should be no audible background noise, in order to allow the
high drama of silence and the quietest pianissimo; and the sound should be
strong to assist the singers of the COC to fill the hall with a fortissimo. Good
singers will be able to sing extremely quietly and still carry emotion to the
last row.
The auditorium envelops the performers, contains and supports the sound in a contemporary horseshoe form.
We developed the undulating walls with the architect to spread the sound and mitigate the negative focusing effects of the concave form. The double pillow forms came out of close collaboration between architect, acoustician and structural engineer.
Auditorium, stage and rehearsal hall are isolated from ground-borne vibration of the adjacent subway and streetcars on high-performance rubber pads.
Design of the auditorium ceiling has been a highly collaborative effort between
architect, theatre consultant and acoustician. From an acoustical perspective it
was important that the ceiling work with the balconies to contain the sound
forward in the room, while keeping the audience in the balcony feeling as though
they are part of the overall experience.
Sufficient areas and locations of openings for stage lighting had to be included in the ceiling, with the required catwalks behind. Having been through this basic design process many times before on other theatres, SSD understood the goals, priorities and design proposals of the theatre consultant and COC lighting staff, and could focus on being creative, not restrictive. Below is a view of the ceiling in context as seen from the proscenium
Orchestra pit
The
design of the pit has a great impact on
the
sound of the orchestra, on the
balance
between orchestra and singers, and ultimately
on the
distance of the audience from the singers. SSD has a great deal of
experience
with these aspects of pit design and with musicians’ concerns of loudness, tone
colour and projection
into the
auditorium, so SSD led the
design
of the orchestra pit,
from dimensions, to shape to finishes. The pit geometry is flexible. The
floor is comprised of 2 large
platform
lifts, each
of which can be set at any
elevation
between
stage level and 2.7m below stage. There are also panels to contain the plan
area and acoustic curtains to absorb sound when appropriate.
Performance Sound, Video and Communications
Performance Sound, Video and Communication systems are included to support the wide range of performance and education needs. The COC is pleased that they no longer have to amplify the singers or the orchestra. So the installed audio system is optimized for sound effects and sound transfer from one place to another; for example, relay to or from off-stage chorus. The system is highly integrated with the architecture so that loudspeakers are not visible to the audience, and the sound effects can blend seamlessly with the natural acoustics of the voices and orchestra. This can enable effects such as voices swirling around the theatre, aircraft overhead, or the surrounding reverberation of a cave. All of the loudspeakers are hidden in the proscenium, pit railings, and ceiling. The system can also enable subtle reinforcement for "Broadway" voices in crossover opera/musicals, such as Sweeney Todd or Candide. Infrastructure and flexibility make it easy to augment the system for highly amplified musicals and concerts. Communication systems link the technicians to each other, the stage to the dressing rooms and relay sound and video to the lobbies.
Because the acoustics for amplified sound needs to be less reverberant than for opera, motorised sound absorbing curtains have been provided around he walls of the auditorium. At a posh of a button they can be extended to dry up the reverberation and create a clear amplified sound.
Other Spaces
The Richard Bradshaw Arial Amphitheatre in the front lobby is a fitting tribute to the man at the COC who worked so hard for so many hears to make this new house a reality. The space will be used for pre-opera lectures, informal concerts and includes a simple, high tech loudspeaker system for speech reinforcement and music playback.
The facility includes a rehearsal room large enough for the COC orchestra to rehearse in a comfortable acoustic when the auditorium is otherwise occupied. Like the auditorium, it is isolated from the ground on rubber pads.
the team
Lead acoustician: Sound Space Design, Bob Essert, Director, with assistance
from:
Aercoustics Engineering: sound insulation, noise control, valued second opinions
Engineering Harmonics: performance sound video and communications systems design
Wilson Ihrig & Associates: building isolation
Architect: Diamond and Schmitt Architects Incorporated;
Theatre Consultant: Fisher Dachs Associates, New York, NY.
Preliminary acoustical advice had been given by Artec prior to selection of SSD.
the link
http://www.fourseasonscentre.ca/
