Making Our World Sound Better Since 1979
Our New Conference Room
St. Paul's Catholic Church, New Bern
Classroom Acoustics coming to the IBC 2018 Building Code
Guidelines for Healthcare facilities
189.1-2015 1st public draft of proposed significant acoustics additions is
S12.70-2016 standard for healthcare speech privacy - (description
New Developments in Backup Alarms - A backup
alarm is an essential safety system for vehicles used at workplaces.
Unfortunately, the sound of the traditional backup alarm can be heard far
away in quiet places. Since it is a sound designed to get attention, it
can be very irritating to those hearing it in places where there is no
danger. Systems have been available for years with selectable levels so
the alarm could be set to the lowest level still loud enough to provide
safety. Also, systems have been available that automatically sense the
background level nearby and adjust the signal appropriately. Now some new
concepts are available to reduce the degree to which these sounds are
heard far from the vehicle.
Interior Storm Windows - As we face more
situations of homes offices and other buildings close to roads or other
noise sources, we face greater needs to increase the sound blockage of
existing windows. The easiest way to do this is usually with a storm
window either indoors or outdoors. Such windows can be of acrylic or
regular 1/8 inch glass. However, the best performance is achieved with
laminated glass ¼ inch thick or in extreme cases thicker. We have
discussed this before, but now we are finding more sources of these
windows. Here are some:
Sliding Doors for Offices - We are seeing increased use of sliding doors for offices and conference rooms without consideration of the privacy issues involved. These doors are usually installed barn style, that is sliding over the wall outside the office, leaving a gap between the door and wall when closed. In some cases these gaps are small and in some they are very large. Often there are no seals of any type. Large unsealed gaps are essentially like having the door open. Sealing systems for such doors are not as readily available as for hinged doors, and the available options will typically not work as well as with a hinged door.
Virginia Court Decision Strikes Down Noise Ordinances
- On April 17, 2009 the Virginia Supreme Court in a case involving a night
club held that noise ordinances in the state based on subjective criteria
or “reasonable person” standards were vague and unconstitutional. The
court essentially held that any noise ordinance in the state must have
quantitative and measurable standards. This leaves many communities
without enforceable ordinances until new ones can be adopted. The ruling
Personal Note from Noral Stewart
Thirty Eight Years. Yes, we celebrate our thirty-eighth anniverary at the beginning of 2017. That is a long history, and one of growth and major accomplishments. I will also be 70 in January 2017. I realize clients must be wondering where we go from here. I intend to keep working some as long as my health permits, BUT, I am not going to be working full time. Starting in 2016, I have been taking 20% time off. I expect that to increase to 40% in 2017. I need to slow down and smell the roses some. I will be taking many long weekends, and much of the summer off. We have known for many years that this time would come when we have to face the future. Many of you have come to know Joe Bridger who joined us first in 1993, twenty three years ago. For several years now, Joe has been managing much of our work. We expect that Joe will be taking over the primary management of the business. In 2015, we hired Chris Eaton to begin taking over much of the work I have been doing, and to develop new capabilities we have been relying on contractors for. He is already doing most of the field work I was doing. In December 2015 we added John Stewart to our stable of affiliates, primarily to handle industrial and machinery noise and vibration issues. In November 2016, Dr. John Gagliardi became a full time employee. This all positions us to allow me to slow down. I will be available to provide everyone with the benefit of my experience, but I will be managing fewer jobs and doing less field work. Stay tuned as there could be other changes to allow us to better serve you.
John S. Stewart, PhD. Affliliate for Industrial Machinery Noise and Vibration Control
Yes, another Stewart, though not related. Noral and John were undergraduate students at N. C. State at the same time. John stayed and completed his PhD while Noral worked for a period in industry. John basically wrote the book when it comes to noise control for wood working machinery. He had a full-time world-wide consulting career specializing primarily in wood-working noise before joining the research faculty of NC State to head a program to develop improved wood-working machinery. During that period he continued to consult part-time. We referred some wood-working industry projects to him. He also has experience in other industries, in vibration control, and in balancing. Since retiring from NC State, he has had a desire for some part-time consulting. Working with us is a natural fit. John will be working with Noral on all our industrial workplace noise control projects with assistance from Chris Eaton as appropriate. He will also be working on any vibration issues requiring measurement and analysis beyond the basic guidance for building systems.
John Gagliardi, PhD returns to our staff
Some may remember John Gagilardi working with us on a part-time basis several years ago. John is now returning part-time at first but working toward a full-time position. John will be based at his home in Salisbury, NC but will be in contact with the office almost daily and will be visiting our office frequently. John did not do his degrees in acoustics but became involved in acoustics and has been a highly active continuing education learner. He seems to have been almost continuously enrolled in acoustics classes from one of the major universities. For the past several years he has been technical director for a materials manufacturer. However, before that he was involved in an acoustical consulting firm and an architectural acoustics test laboratory. John will be working heavily with Joe on architectural projects but will also be doing field investigations, especially in the western part of the state.
Our Interns – Sidd and Julius
Sidd Mahajan and Julius Elo joined us in the summer as interns. They are MS students at NCSU in acoustics. They have had the opportunity to work on and visit jobs with us as well as helping us with many things around the office. Julius graduated and left us in December but Sidd will be continuing in 2017.
Stewart Acoustical Consultants and AVCON are featured, with key personnel Frank Yarborough and Eb Strickland of AVCON, and Joe Bridger and Fred Schafer of our firm in this educational science production (6 minutes), which was born out of the work being performed on the cathedral.
Stewart Acoustical Consultants teamed with AVCON to design a loudspeaker solution that would provide optimal speech quality. Fred Schafer and Joe Bridger led this effort for our firm. Our interns (Siddharth and Julius) and Mathew George and his staff were integral in the construction of the EASE acoustics model, and subsequent AURA analysis. The EARS module was used to develop high quality auralizations that demonstrated to the Diocese of Raleigh the acoustical character of the space for music and unamplified speech, and the optimized speech quality provided by the loudspeaker system design. AVCON provided critical input on client requirements and is providing the full system drawings and installation. In addition, our firm was tasked to evaluate the acoustics as designed, and provide sound isolation and HVAC noise control solutions. The dedication of the building is scheduled for July 26th, 2017.
Worship Space Acoustics - Three Decades of Design
Several years ago we presented several posters on many of our worship space projects at a meeting in Providence, RI. The plan was for the Acoustical Society of America to compile a book of those posters. Well, it took a while but the book has been published containing case studies resulting from most of the posters we presented. The book is published by Springer Verlag and is available from many sources including Amazon.
New Realistic Sound Demonstration Equipment
We have expanded our ability to present high quality auralizations and other sound demonstrations using specially selected and calibrated headphones and preprocessing tools. This can be set up with visual walkthroughs and general visuals to orient the listener. To make auralizations, we take a carefully selected dry source and convolve it with the room’s impulse response, to create a binaural sound file with the room’s character now added. With the new equipment, very realistic demonstrations for multiple listeners is now easily accomplished
SoundPlan – Advanced Analysis of Environmental Noise
We have been using Soundplan and CadnaA for specific project needs for several years using short-term licences to calculate and plot sound propagation outdoors in detail. We have chosen to purchase a fully featured version of SoundPlan. With this program, we can import from Google Earth and other sources the geographic information system (GIS) data and image overlays as well as site plans to develop more precise and complex noise propagation maps for all kinds of sources, whether building equipment, transportation corridors, aircraft, outdoor venues (loudspeakers) or industrial sources. We can properly assess outdoor mass evacuation systems with this tool. It allows us to more efficiently problem solve, and develop cost effective solutions and display results in a way that is easier for everyone to grasp (using color plots and contour maps).
The primary use will be to plot contours of sound radiated from sources in accordance with ISO 9613. The program also contains a module for highway sound propagation similar to the FHWA TNM program and another that allows highway model calculation using the actual TNM program. Other capabilities include calculation of sound indoors in industrial spaces and evaluation of the sound escaping to the outdoors. This program greatly enhances our ability to analyze and illustrate results for complex outdoor situations.
50 Years for NC Chapter Acoustical Society of America
The NC Chapter of the Acoustical Society of America celebrated its 50th Anniversary with a meeting at the Durham Bulls Athletic Park. A highlight of the meeting was a tour of the renovated Baldwin Auditorium at Duke University conducted by Mark Holden, Duke alumnus of Jaffe Holden Acoustics who converted the room from a mediocre auditorium to a world class multipurpose space. The photo below is of the chapter chairs (and one vice chair) who were present, most of whom have connections to us.
Akay and Bailey inducted into NCSU Mechanical Engineering Hall of Fame
Upon nomination by Noral Stewart, Dr. Adnan Akay and Dr. J. Ronald Bailey have been inducted into the NCSU MAE Hall of Fame. Akay was Chair of ME at Carnegie Mellon and a Director of the US National Science Foundation and is now professor, chair of ME, and Provost at Bilkent University in Turkey. Bailey was a professor at NCSU, helped found this firm, led IBM Robotics Engineering for several years, and was Dean of Engineering at three schools before retirement.
Meet Royster Award Winner Nicolas Morales
The ASA North Carolina Chapter held its student poster competition, including the Royster Award, on Friday November 11. Thirteen posters were submitted. There were 9 graduate student entries, 5 of which were eligible for the Royster Award, and 4 entries from undergraduate students. In addition to the $2500 Royster Award, the chapter provided $2000 in prizes open to all graduate students and $500 in prizes for the undergraduate students. Nic’s poster presented a novel approach for optimizing acoustic parameters for computer-aided design and analysis of architectural models. During the meeting Joe Bridger gave a talk entitled “Cathedral Acoustics - a Case Study”. Click here for summary of the awards.
Welcome Chris Eaton – We are very pleased to welcome Chris Eaton to our firm. Chris is a native of Davie County (like Noral Stewart) and a MS graduate of the acoustics program in the Department of Mechanical and Aerospace Engineering at NC State. Chris has had a long and successful career in product acoustics in the automotive and communications industries which has led to 25 issued patents. He has impressed us with his grasp of acoustical fundamentals, and he brings the skills of a seasoned professional with consulting experience. His experience in the automotive industry and with HEAD Acoustics included a strong emphasis on the area of “Sound Quality,” a methodology that so far has been applied primarily to products. We look forward to opportunities to possibly apply some of that experience to the sound quality of buildings and environments. He has also developed successful award winning audio products for telecommunciations. Thus, he may assist in audio areas. However, he will be primarily working with Dr. Stewart in the areas of environmental/community noise and sound isolation. He has been doing ASTM isolation testing and envirornmental sound measurements as he has been learning new applications of his talents. As part of this, he will be accompanying us on many visits with clients which will give you an opportunity to meet him.
AIA Credit Course in Architectural Acoustics Available -
Both Noral Stewart and Joe Bridger have been certified by the
Acoustical Society of America as presenters of a one-hour course in
acoustics that qualifies for health, safety and welfare credit through the
AIA. The basic one hour course must follow slides provided by ASA but can
be supplemented with the experience of the presenters and special topics
of interest to a particular audience. Stewart Acoustical Consultants is
pleased to provide this class on a limited basis free of charge to small
groups in our office, or to larger architectural firms at their offices in
the Triangle Area. We are also open to presenting the class to multi-firm
groups of students at locations outside the Triangle area such as at AIA
Section meetings. Please contact Noral Stewart or Joe Bridger for