Brenda’s thoughts on 2016

by Brenda Brown

Two thousand sixteen is quickly coming to an end.  I hope this means things are winding down so you can enjoy the holidays.  It is also a great time to reflect on the year with thanksgiving.

Pat & Brenda Brown, Don & Carolyn Davis

Pat and Brenda Brown, Don and Carolyn Davis 1996

In 1996, Don & Carolyn Davis provided us with a great privilege to continue their mission. Pat and I just celebrated our 20th anniversary at the helm of SynAudCon. I am often silenced with awe as I think about the last 20 years. Over the years, the computer has become a hand-held device, the world wide web has entered into our lives, we’ve seen the industry gradually change from analog to digital, and audio contractors have grown into integrators whose responsibilities now includes all facets of media.

As times changed, so has our approach to teaching.  We progressed from overheads, to video projection and now to online training.  A short video has replaced a chapter in a textbook. SynAudCon is teaching many of the same principles, but using modern delivery systems that shorten the learning curve of the student. Read more

Hemispherical Loudspeaker Balloon Data Using an 1/2-space Mic Array

Practical_Audio_Header

Pat Brown shows a technique for collecting fast, accurate hemispherical loudspeaker balloon data.

I frequently get requests to measure hemispherical loudspeaker balloon data for ceiling and wall-mount loudspeakers. This information must be collected in half-space, so in 2016 I built a mic array for this purpose.

The array consists of 19 microphones at 5 degree angular resolution. The concrete floor was excavated to house a 1 x 1 x 1 meter stainless steel-lined “pit” that houses a motor-driven turntable (LinearX LT360).

The rig allows the measurement of boundary-loaded loudspeakers with any acoustic symmetry – polar, 1/4, 1/2, or none at a 2 meter microphone distance. The time window of 60 ms provides a frequency resolution to about 50 Hz.   Read more

How Sound Behaves As It Hits Different Types of Surfaces

by Brenda Brown

Acoustics First® produced three video simulations to help us visualize how sound behaves as it hits different types of surfaces.

Many of us enjoy spending time with our family over the holidays. I come from a large family so we usually have 30 (10 are under the age of 8) at our Thanksgiving dinner. This year it was held at my sister’s home who has the typical open-space floor plan with hardwood floors. This look is often seen in the newer homes.  The noise level was almost unbearable at times.

Being married to Pat Brown, we have acoustical treatment on the walls, ceiling and carpet on the living room floor.  Our kitchen has hardwood floors but the living room and kitchen are in separate rooms. The experience is totally different. Our space is so much more enjoyable.

We all love instructional videos.  With the use of videos, we can understand things in a few seconds that once took a long chapter of text. Acoustics First® has produced three video simulations to help us visualize how sound behaves as it hits different types of surfaces and why our space is so good and my sister’s space is not. Read more

SynAudCon’s ECS: Design and Deployment Seminar

by Brenda Brown

Highlights from the ECS: Design and Deployment seminar.

SynAudCon was in Washington DC last week presenting our ECS: Design and Deployment Seminar.  It was neat being in a historical city during an historical election.  Those who attended the seminar are now aware of historical changes within our industry.

For 43 years, SynAudCon has been offering one-time events as new technologies develop so we can get our attendees up-to-speed quickly.  Of all the one-time special events offered in the last 43 years, this event presented the greatest opportunity for sound system practitioners.

Wayne Moore, Larry Rietz and Bill Nattress presented the new code changes – where it is going and ways to work with the Authority Having Jurisdiction, or AHJ. They presented cases where pro audio systems are now being used for ECS announcements.  Their passion to save more lives through use of the house sound system was clear in their presentations.

For two days, Pat Brown presented ways to design an intelligible speech system in live, reverberant and noisy spaces.  He drove home the points with a site visit to the historic St. Paul’s Episcopal Church.  Sander van Wijngaarden helped us understand the process behind measuring speech intelligibility, with hands-on exercises at the site using STIPA meters.

It took 4 days to cover the information properly, but this group of attendees gained insights that will be extremely beneficial to their companies.

The room was filled with AV practitioners/engineers with an average of over 25 years of experience.  A good percentage had over 35 years. Combining knowledge with years of experience brings wisdom. Presenting this information to this group is sure to ignite some new products and business opportunities that will come back in revenue. More importantly, the sound reinforcement industry is now part of the equation for saving lives through emergency announcements. There are collaboration opportunities with the fire alarm industry. An important take-away from the event is that sound reinforcement systems and IP networks will be major players in mass notification systems. Many of the seminar’s attendees were forming alliances and scheduling meetings before the event even ended. The future is bright for the proactive.

Our deepest gratitude to the presenters for their willingness to share this information with the attendees.

Enjoy viewing some photos taken at the event.

ECS: Design and Deployment Seminar - site visit

Pat Brown demonstrated that the room’s impulse response can be collected by simply popping a balloon.

 

ECS: Design and Deployment Seminar - collecting the room's impulse response

Pat Brown demonstrating how to collect the room’s impulse response.

 

ECS: Design and Deployment Seminar - Attendees measuring STIPA

Attendees measuring STIPA at the site visit.

 

ECS: Design and Deployment Seminar - Sander van Wijngaarden

Sander van Wijngaarden from Embedded Acoustics

 

Wayne Moore from Jensen Hughes

Wayne Moore from Jensen Hughes

 

Larry Rietz from Jensen Hughes

Larry Rietz from Jensen Hughes

 

Bill Nattress from Biamp

Bill Nattress from Biamp

 

ECS: Design and Deployment Seminar - listening demos

Pat Brown uses an in-ear listening system so the attendees can hear the demo without the classroom reflections.

 

ECS: Design and Deployment Seminar - mealtime

Mealtime provides a great opportunity to share and learn.

 

ECS Deployment Class Photo

ECS Deployment Class Photo

 

ECS Design Class Photo

ECS Design Class Photo

 

Sound Reinforcement Solutions for Emergency Communication Systems

Emergency Communication Systems Icon

Why AV Integrators Should Be Involved in MNEC Solutions

The topics of Mass Notification and Emergency Communications (MNEC) initially conjures us mental images of a smoky room illuminated by flashing strobes. A barely intelligible message from a 4-inch loudspeaker attempts to cut through the din and deliver life-or-death instructions to the building’s occupants. Fortunately, this often works, and lives are saved.

A major problem is that this mode of message broadcasting does not scale with room size. This results in large, noisy, reverberant spaces being served by the same limited-fidelity strobe loudspeakers as the small, dead office environment. The intuitive “fix” is to do what a lighting designer would do to achieve more illumination for a dark room – just add more fixtures. Unfortunately, sound isn’t light, and adding more loudspeakers can actually reduce the intelligibility of the emergency messages. The MNEC community has learned the hard way that a broader pallet of tools and different type of expertise are required to deliver MNEC messages in large spaces.

The good news is that both the tools and the expertise already exist. Nothing new needs to be invented. The reproduction of intelligible speech in large, noisy, reverberant spaces is right up the alley of the sound reinforcement industry. In fact, there is a good chance that the difficult acoustic space that can’t be reached by fire strobe messages already has a sound reinforcement system that is used daily to communicate to the occupants of the space. It makes perfect sense to route the emergency announcements to the house sound system, and that is exactly what NFPA72 has been expanded to allow.

There two paths for bridging the divide between the fire alarm and sound reinforcement industries in order to increase the effectiveness of MNEC systems.

  • Equip fire alarm companies to deploy sound reinforcement solutions.
  • Bring the MNEC system into the scope of the sound reinforcement professional.

Both paths require training, and fundamental to each is the need for selecting and placing loudspeakers based on the room’s acoustics. There are software tools that can speed the process, but these require human decisions and expertise on the part of the user.

Once an intelligible system has been designed, there is a need for integration with the MNEC system. This requires knowledge of the code, and an understanding of the sound reinforcement hardware. In addition, the finished MNEC system must be tested to assure that the intelligibility objectives have been reached.

Most professionals attempt to glean the need information from various sources. But, this is research, and research requires time. There is also the danger that some important aspects are missed along the way. The best solution is to learn the fundamentals from people who are already doing it. Synergetic Audio Concepts, Inc. has created a training opportunity for the MNEC and sound reinforcement communities.

Emergency Communication Systems (ECS) Design and Deployment is a two-part event.

Emergency Communication Systems Banner Ad

Part 1 – Design

Emergency Communication Systems Seminar Staff

presents a sound system design process that is based on the room’s acoustics, allowing the selection and placement of appropriate loudspeaker(s) to achieve on a target intelligibility score. Most importantly, the process considers the influence of background noise and room reverberation on the sound clarity. A systematic design approach allows the performance of the ECS to be evaluated at the drawing board, where design changes are easy to implement. Instructor – Pat Brown

Part 2 – Deployment

examines important changes to NFPA72, with emphasis on Chapter 24 – ECS and Annex D – Speech Intelligibility. Special topics include handling the Acoustically Distinguishable Space, Speech Intelligibility Testing, and the Fire Alarm/Paging System interface. World-renowned subject matter experts will present the topics, with ample time to answer specific questions regarding MNEC systems. Instructors – Wayne Moore, Larry Rietz, and Sander Van Wijngaarden.

Why spend years sorting through a sea of information, when you can get it all in one place, at one time? ECS Design and Deployment will dramatically reduce the learning curve and allow both fire alarm and sound reinforcement professionals to capitalize on code changes.

 

For more information, please chick here.

Amplicalc – Free Power Amplifier Calculator by SynAudCon

Practical_Audio_Header - Power Amplifier Calculator blog

 

 

 

 

Amplicalc is a free “power amplifier calculator” developed by SynAudCon. This useful tool will help you select the proper amplifier. Video tutorial is included.

As simple as audio power amplifiers seem to be on the surface, selecting one for a loudspeaker is tricky. This is partly due to the completely different criteria used to establish amplifier power ratings vs. loudspeaker power ratings. The former is a measure of production. The latter is a measure of endurance. Our power amplifier calculator freeware AmpliCalc™ helps remove the mystery.

A new version of AmpliCalc allows you to select the amplifier’s sine wave rating, and then determine the RMS voltage (and continuous power) delivered to the loudspeaker by considering the signal’s crest factor.

Now, the user can work the problem the other way, starting with the loudspeaker’s power rating, and then determining the required amplifier sine wave rating based on the crest factor. Either way, AmpliCalc takes the mystery out of audio power amplifier sizing.

You can download AmpliCalc here.

The video below gives an overview of the new features.   pb

 

 

 

Ten "70 V System" Myths

Practical_Audio_Header

“70 V Systems” Needn’t Be Confusing

Of all the topics covered in SynAudCon courses, few are as misunderstood as “70 V” systems. Most people are surprised to find that these systems share many common traits as “direct” connected systems. The most important trait of these systems is the use of transformers on the loudspeakers (usually internal) to “step down” the signal voltage before applying it to the loudspeaker. This is necessary because the signal voltage is “stepped up” at the amplifier. In fact, at SynAudCon we prefer the term “transformer distribution system,” especially since they can be based on voltages other than 70 V.

The ratings and specifications are based on sine waves, but any audio signal can be played over the system.

Read more

Ten Reasons Why Church Sound Systems Cost More

Practical_Audio_Blog_Header

In a day of mail order mania and cost consciousness, remind your church sound customers of some basic truths

by Pat Brown

A letter to a church sound committee might read:

Thank you again for the opportunity to provide you with a proposal for the sound system for your house of worship. While we appreciate your interest in “good stewardship” in the funding of this project, and understand your request for “church pricing” for the work, the following points should be kept in mind when determining the best value for the dollars spent. Read more

Pat's Blog – New Learning Resources

Practical audio resources

Educational Resources For Audio Professionals

Here are some new web resources to help you continue your self-education at the time and place of your choosing.

Filter Hose v2
First, there is a new version of a powerful FIR development tool – Filter Hose. FH is a FIR toolbox for audio practitioners. It accepts input data in many forms, and allows you to sculpt a FIR filter to meet your needs. It is low cost, and a light version will be available soon. The tutorial videos on the HX Audio Lab website are great learning tools. I mention it here because FH is platform-independent and works with data from virtually any measurement system.

Read more

On-Site RIR Survey

Practical_Audio_Header

Site Survey: Room Impulse Response (RIR)

Preparations for this fall’s Making Wireless Work seminar are underway. Our members wanted an east coast event. Based on recommendations from the seminar staff and others, the site is Newark, NJ. There is a major airport nearby, local mass transit, and good access from the East coast rail system.

We were in Newark last month conducting Sound Reinforcement for Technicians and took the opportunity to do an informal site survey of the hotel and area. So, how much info can you get, armed with only an iPhone?

The Area
Below is a photo of the area. The Robert Treat hotel is just to the left of the blue sign. This is the seminar site. The New Jersey Performing Arts Center (NJPAC) is just to the right of the sign. Read more