Acoustical Studies and Design Engineering
We regularly deliver acoustic, vibration and noise control studies, but one of our main activities is providing acoustic design engineering for architecture and system integration for all domains of building construction and renovation.
For example :
- Conference rooms, amphitheaters, lecture rooms, classrooms ;
- Concert halls, theaters, auditoriums, recital halls ;
- Public meeting rooms, and town halls ;
- Music conservatories, music schools, music rehearsal rooms ;
- Performing art centers, dance rehearsal rooms, theater rehearsal rooms ;
- Schools, universities, high schools, junior high schools, elementary schools, day care and kindergarten ;
- Spaces for worship, Churches ;
- Recording studios, film auditoriums, dubbing stages, foley Stages, vocal rooms, music studios, multichannel control rooms, cinemas ;
- Lunch rooms and cafeterias ;
- Gymnasiums and swimming pools ;
- Living spaces, apartments and houses ;
- Restaurants, hotels.
Diagnostics and solutions for noise and reverberation control :
- Diagnostic measurements for rooms acoustics, noise and vibration ;
- Interior acoustic values for reflectivity and reflections ;
- Sound isolation, impact and shock isolation ;
- Environmental noise control through building envelop design ;
- Domestic noise reduction between spaces or from the exterior ;
- Speech intelligibility optimization ;
- Noise control for occupied rooms ;
- Noise control for machines and equipment ;
- Solutions are also evaluated in terms of fire, toxicity, hygiene, security, access and universal design for public spaces.
Studies in France respond to the criterion « HQE » « Haute Qualité Environnementale ».
In the US, LEED certified designs, ;
Acoustic, Vibration and Impact Measurements
We provide measurement results for airborne noise isolation, impact isolation, structural vibrations, and general room acoustic measurement results based on ISO3382 such as ETC, RT60, RTxx, C50, C80, Clarity, Center Time etc.:
- Impulse responses taken inside rooms with MLS (Maximum Length Sequence) or Esweep then filtered 1/3 octave ;
- Ambiant and environnemental noise measurements ;
- Work related noise levels and control ;
- Measurements of impact or shock transmission levels throughout and between buildings ;
- Occupied noise level limits such as cafeterias, classrooms, gymnasiums;
- Machinery generated noise (HVAC, elevators, kitchens and food handling equipment noise, industrial machinery noise etc.) ;
- Occupied noise levels (restaurants cafeterias, day care, schools, public gathering places, classrooms etc.) ;
- Measurements for musical envelopment/clarity ratios for the musicians and for the public
- Overall frequency response of the direct plus 300ms early energy ;
- General isolation indexes for interior/exterior requirements.
Measurement equipment :
- Room measurement system STENTOR® (hardware et software), impulse responses MLS with post treatment ISO 3382, (filters class 0), time window are variable from 1ms to 5 seconds,
- 4 low noise mic preamplifiers and convertors
- Mic rail system for area mapping measurements
- Microphones Earthworks M60
- Speech intelligibility source - microprocessor controlled calibrated directional source
- Wide band multi directional high power source
- Source de Pink/White/Sweep Noise Neutrik
- Impactor 1200N
- Custom multiple pulse streams for transient isolation evaluations
- Brüel & Kjaer Type 2260 Investigator Sound level meter with software BZ7210 (classe 0)
Acoustic, Vibration, Absorption and Reflectivity Models and Simulations
Acoustic prediction software
We use many different software packages to modal each of our projects. CATT-Acoustic allows us to predict reverberation times and the standard metrics based on the ISO3382.
STENTOR® model software allows us to model first and second order reflections for speech, music and noise control. Both programs use 3D views for complete control of the definitions of the surfaces, objects and occupants in any room.
Acoustic measurement software
STENTOR® measurement software uses up to 4 microphones, and offers octave or 1/3 octave noise measurements, MLS, calibrated class 0 filters, variable time windows 1 ms to 5 seconds,
Reverberation time, EDT, clarity, early to late ratios, lateral to frontal ratios, envelopment, strength, useful early reflection specifics (spectra, time, level).
Dirac - Room acoustic measurements
Clio - Loudspeaker measurements
B&K 2260 - with proprietary software for data treatment
3dsMax - 3D rendering software
And many, many proprietary programs created in house
Engineering team (=> lien vers autre page « Moyens techniques »)
Our engineers are regularly developing new tools (both hardware and software) for acoustic predictions, measurements and data treatment.
All of our CATT Acoustics models are prepared by Richard H. CAMPBELL, CATT specialist and acoustician in East Falmouth Massachusetts.
Signal treatment, filters and MLS software is written by acoustician Nicolas Teichner.
Sound system and studio monitoring systems are procured and integrated by Jeroen van der Klugt.
Structural engineering calculations and designs are provided by Albert MARCO building and structural engineer - BRTM.
AutoCAD plans are prepared by architects Dominique FALCOZ and Natalie ALVES. ;
Isolation and Noise Control Engineering
We have been directly involved in the design and construction of rooms of all sizes intended for audio or video production, voice or music recording, music rehearsals rooms, and large rooms such as concert halls and performance auditoria, which require a high level of sound isolation.
We are also involved in industrial noise and vibration isolation, noise control in schools, economical solutions for noisy neighbors in apartments and homes, and work place comfort noise control studies.
Consulting with Architects, Engineers, Interior Designers
In the case of construction or renovation projects, as consultants we offer architects, interior designers, and construction management teams guidance and assistance before, during and after the construction in the following ways :
Initial or pre-design phase - approval of the preliminary designs and drawings (APS - APD)
We can provide the current guidelines, regulations and recommendations published locally, regionally and nationally. From these along with any on site measurements, we provide the working performance specifications that will be referenced to as target values to be achieved. These objectives can be associated with current guidelines such as HQE, LEED, Qualibat. The feasibility of the project is then evaluated in regards to projected cost/value/objective ratios.
Project Phase (PRO)
Nous recherchons des solutions adaptées, afin d’atteindre les objectifs en termes d’isolation phonique et de caractéristiques acoustiques intérieures, dans le respect de l’enveloppe budgétaire allouée au projet et des normes en terme d’hygiène et de sécurité relatives au type de lieu. Notre mission intègre l’établissement d’une notice technique et d’un cahier des charges pour la consultation des entreprises. Nous réalisons les plans détaillés d’exécution pour l’installation des traitements acoustiques.
Realization and construction Phase (REA)
Building site visits and coordination meetings are regularly required during the construction phase. One of the most important links between the design team and the building contractors is the complete and accurate transfer of understanding of the construction details. The detailed plans must be complete but as importantly the successful presentation of these plans on site can mean the difference between a fair result and an excellent result whether the project involves noise control or room acoustics or both..
Project Delivery or Reception Phase (REC)
The acoustic and vibration measurements commonly specified to validate the quality of the work at the end of the building phase all the design team to verify whether the objectives set forth in the original pre-design phase have been met. The measurement results are presented in the final report that also describes the materials and methods used.
Plans and Detailing for Construction
We firmly believe that a key factor in the success of a project is in the communication between the design team and the builders, and for this reason we pride ourselves in our detailed plans for construction of the acoustic components. Architects enjoy the ease of plugging our “acoustic detailing” .dwg files into their designs, while the accompanied text offers the contractor specifics that can optimize the construction.
- Floating floor detailing with elastomers or springs ;
- Floating isolation wall/ceiling structures and assemblies ;
- Acoustic and structural detailing for the installation of acoustic doors, windows, ventilation ducts and sound locks ;
- Hundreds of interior acoustic treatments and assemblies with noise control data.
- Systems for vibration, impact and shock control ;
- Plans that clearly define equipment positions for accurate monitoring or sound system integration ;
Construction Supervision, Estimating, Scheduling and Coordination
Over the last 25 years, we have been responsible for the coordination and construction supervision for the majority of our design projects. This has offered us invaluable experience in building construction. For the last 15 years we have offered training assistance to builders interested in developing their understanding of acoustic installations. On site testing routines to verify compliance with design goals is part of our weekly schedule.
Cost Control and Project Status Reporting
Our visits and reporting of the status of a building project during construction allow the performance of the acoustic designs to be verified phase by phase, therefore changes or corrections can be implemented immediately. At the end of a project, measurements are taken and integrated into our models to produce a view of the variance between the objectives, predicted results and the measured results. In some cases like sound isolation renovation, measurements are taken before construction and after construction to demonstrate the value of the increase in isolation. For pro audio, the control room monitors are measured and calibrated and the "sweet spot" around the engineers position is mapped.
Feasibility Studies
Feasibility studies are often required during the pre-design phase for both new constructions and renovations to define the acoustic objectives along with the potential cost. These studies generally involve measurements and models and often several solutions that provide a range of cost/value ratios. Live and dead loads, construction complexity and time required can influence the feasibility.
Environmental Impact Studies
We have been awarded many projects to do pre-design environmental noise impact studies. In these cases we evaluate the risk annoyance factors of both noise emissions or noise intrusions, with regard to the future activities within the proposes structures and the surrounding environment. This can involve isolation proposals with costs and construction schedules. Projects like this have included predicted noise generated from a future outdoor public swimming pool in a residential neighborhood. The risk of noise emergence from music clubs, concert halls, disco techs, cinemas, music rehearsal rooms, music schools in proximity to quiet residential neighbor hoods, the control of impact noise from a dance hall to be built above a lecture hall, loud music studios in residential complexes, noise intrusion risks for a post production recording faculty built next to a highway.
Sound System Design and Integration
Since the late 1970's we have been involved in both the electro-acoustic design of sound systems as well as the acoustic principles of the various installation styles and techniques.
Speaker design, amplifier design, microphone pre-amplifier design, compressor design, gain before feedback strategies, installation variations for speech intelligibility for large and small lecture halls, systems for the hearing impaired, systems for worship spaces, general announcement and public warning systems have all been missions that we have taken on with passion.
Systems for music performance are generally based on an entirely different protocol then for speech intelligibility, in that the spectra and peak sound levels for music performance are specific to the type of music and the sensation of enjoyment of music is generally related to the sense of comfortable envelopment and balance between the musical timbres.
Speech intelligibility on the other hand, requires that reverberant factors in a hall be limited while the speech frequencies are increased and enhanced. We have built many custom designed systems to meet the exact needs of clients and the results were always both cost effective and widely acclaimed for their clarity.
