Light poles may often provide the best placement option for a loudspeaker servicing an outdoor venue. However, when utilizing this attachment technique, additional design criteria need to be considered to insure the loudspeaker is properly and safely mounted. The exercise presented below is intended to outline the process involved. Prior to installation, review and approval by a structural engineer is always required.

EPA (Effective Projected Area) is a value assigned to a pole mounted fixture and hardware. In this case, it’s the loudspeaker. EPA is used to calculate the wind load that the pole will be subjected to with the loudspeaker and other fixtures attached to the pole. Pole manufacturers rate their products with different EPA values for different wind zones, which vary by geographical location and local building codes.

Let’s look at an example. Can a Community R5 loudspeaker be added to a currently specified light pole? The specifications for the pole state it is designed to meet AASHTO (American Association of State and Highway Transportation Officials) standards for a 100 mph three second gust, with a maximum fixture EPA 3.5 ft2. The pole specifications also state it can support a fixture weight of 88 lbs.
The light fixture attached to the top of the pole has an EPA of 2.48 ft2 and a weight of 20 lbs.

The pole will support the light fixture, but what about the loudspeaker? Upon request, Community provided data for the R5 loudspeaker: an EPA of 2.38 ft2 and a weight of 46 lbs. The sum for both the EPA and weight for all fixtures attached to the pole is calculated. Even the though the combined weight is within spec, the combined EPA of 4.86 is well above the maximum value specified.

The solution in this case was to substitute a different light pole with a larger diameter and thicker wall, which increased the maximum EPA to 7.0 ft2. This substitution was evaluated and verified by the pole manufacturer’s engineering department.

In a recent conversation with a client, the subject of BRC’s commitment to making acoustics an integral element of sustainable design came up. The client’s response was to the effect that, aside from keeping people from suffering hearing loss, there isn’t anything sustainable about acoustics. This is a subject that merits discussion, because a lot of people would agree with that assessment. They would be wrong. Here’s why.

Sustainable design isn’t just about carbon footprints and conservation of resources. The American Institute of Architects’ definition of sustainable design comprises several elements, including the enhancement of livability, comfort, and productivity. When LEED® requires limiting background noise levels and reverberant noise buildup in occupied spaces, it’s right on target for livability, comfort, and productivity.

The question is – so what? Livability and comfort are important to keeping people satisfied in the workplace, and productivity is what keeps business moving forward, but is acoustics really a major factor? Turns out, it is. For verification, one need only read the post-occupancy evaluations of office buildings done by the University of California’s Center for the Built Environment (www.cbe.berkeley.edu ). Their studies include new buildings, not-so-new buildings, green buildings, and non-green buildings throughout the United States. A lot of them, with tens of thousands of survey results based on individual responses from people who work in those buildings. In every case, the Indoor Environmental Quality (IEQ) category receiving the lowest marks is Acoustics (other categories include Thermal Comfort, Lighting, Air Quality, Office Furnishings, and Cleanliness & Maintenance).

So acoustics is a big deal. Not only that, it’s the IEQ factor that offers the greatest opportunity for improving the workplace environment.

But we don’t have to restrict our analysis to these important but less-obvious aspects of sustainable design. Most people think of sustainable design as being geared toward energy reduction and efficiency. Good acoustical design offers opportunities here as well. For example, insulation made of recycled fabric can be specified as acoustical insulation to enhance sound isolation between spaces. And, in general, HVAC systems designed for quiet operation use less energy than those designed without regard for noise.

There is an emerging recognition of the contribution acoustics makes to sustainable design. Look for future versions of LEED® for Schools, New Construction, and Neighborhoods to include new and more stringent acoustics credits.

The calibration methods taught in the ISF Commercial class optimize a display’s picture quality for the space in which it is installed. The main areas of focus include:

• Maximizing Contrast Ratio
• Optimizing Gray Scale
• Optimizing the Gamma Curves
• Optimizing Color Space and Reproduction
• Flat Field Uniformity

Video displays are never setup properly, as delivered by the manufacturer, and calibration is often overlooked by AV contractors. A properly calibrated display will maximize a client’s return on investment and they will enjoy the highest image quality.

The images shown on the figures below are from a recent audiovisual project utilizing Revit software. Revit is a three dimensional BIM (Building Information Modeling) program aimed at reducing waste and improving accuracy by identifying issues early in the design phase. Consultants from different disciplines link their files to a central project file. Changes made by one discipline are globally updated, allowing greater collaboration between designers. AV companies, including Creston, Christie, DA-Lite, Draper and Digital Projection have created Revit models for their products. Models can also be created by importing CAD files into Revit, such as the JBL speakers shown in Figure 1.

Figure 1, Loudspeaker Placement

Figure 2, Equipment Rack

Figure 3, Hinged Wall Mounted Equipment Rack, Open

You’re at a cocktail party along with a lot of other people in a large room, and the noise of so many people interacting makes conversation difficult. In order to be understood, you raise your voice and begin to lengthen syllables slightly. It works, so others in your group do the same. But pretty soon everybody’s doing it, so you have to raise your voice even more. There’s not an app for that, but there is a name for it. And it’s not the Cocktail Party Effect, although that’s what many people erroneously call it.

What we’ve described is the Lombard Effect, named for the French scientist who first described it in 1911. It doesn’t just happen at cocktail parties – it is a natural response when communicating in a noisy environment. And it has been documented in birds and whales, so it is not solely a human response to noise.

There is a Cocktail Party Effect, but it works in the other direction. This term refers to the ability to focus one’s attention on what another person is saying and “tune out” other nearby conversations. Lucky we have it, or the Lombard Effect would get completely out of hand.

And there’s another related effect. A person focused intently on a conversation and disregarding others will often be distracted if his or her name is said by someone outside the conversation. And that’s called … the Own Name Effect. (OK, the name’s from Wikipedia and we haven’t been able to verify it, but it sounds good and everyone so far agrees that, whatever it is, they’ve experienced it.)

The Americans with Disabilities Act (ADA) established requirements to prevent discrimination, remove barriers, and adhere to established design practices insuring access for people with disabilities. Audio systems requirements fall under section 36.303, Auxiliary aids and services.

The original 1991 standard has been updated to the 2010 standard. Changes include:
• Receiver Hearing-Aid Compatibility – The assisted listening system will need to interface with hearing aids. This is accomplished by the addition of a neck loop to the receiver, which interfaces with a telecoil in the hearing aid.
• Required Systems – Assisted listening systems are now required when sound reinforcement is utilized.
• Receivers – The number of receivers required is no longer 4% of seating capacity. Instead, the minimum number required is scaled to the capacity of seating in the assembly area.

BRC has donated funds to help microfinance groups and individuals worldwide through the Kiva Organization. This is a non-profit group which “envisions a world where all people – even in the most remote areas of the globe – hold the power to create opportunity for themselves and others.”

Our portfolio includes:
• A single mother in the Philippines who has a variety store selling soft drinks, sugar, and tinned sardines to her community. She wants to expand her small business to include more beverages, detergent, spices, etc.
• A man with 5 children in Tajikistan who wants to expand his rural farm.
• Five teachers in Sierra Leone who want to buy housing materials such as corrugated roofing, nails, boards, etc. to improve their own homes.
• A 34 year old man who lives with his wife and 3 daughters in a yurt in Mongolia who has a welding business and a taxi service on his motorcycle. He wants to expand both businesses to better support his family.

These four entrepreneurs will borrow the money, pay it back on a schedule, and then the money will be lent to more applicants. The mission is to connect people through lending to alleviate poverty worldwide. To find out more about this organization, please visit their website at www.kiva.org.

BRC is committed to serving our communities both locally and globally.

The AVnu Alliance recently issued a press release announcing IEEE publication of the AVB standards (IEEE 802.1AS, IEEE 1722 and IEEE 1733). The alliance has support from prominent professional AV companies including; Bosch, Yamaha, Biamp, Harman, Shure, Avid, Meyer Sound, and Sennheiser.

It appears CobraNet, the current networked audio distribution protocol, will be challenged by AVB. AVB utilizes an open standard, as opposed to the proprietary CobraNet standard marketed by Cirrus Logic. While CobraNet has found acceptance in the professional AV market, AVB appeals to the automotive, IT, and consumer electronics markets. The magnitude of these markets should allow AVB integration at lower price points.

AVB has performance advantages over CobraNet as well, including support for video and video conferencing content, lower latency, and support for more than 32 audio channels. Network infrastructure will require AVB-enabled switches to route content, but the protocol was designed to allow AVB networks to communicate with non-AVB devices. This will allow upgrading existing network infrastructure to support AVB without having to replace every non-compliant device connected to it.

CobraNet will not become obsolete overnight. Currently more than 50 manufacturers have outfitted their products with CobraNet connectivity. CobraNet has been implemented successfully in numerous projects and continues to work well, but with the advantages AVB has to offer, CobraNet’s utilization is positioned to decrease over the coming years.

Jeremy Aho has just completed Crestron’s Digital Media Certified Designer Course. Crestron DigitalMedia was developed to meet the challenges of the digital era.

The class focused on topics presenting a unique set of design challenges including HDCP (High-bandwidth Digital Content Protection), EDID (Extended Display Identification Data) and copper / fiber optic infrastructure. The design class focused on the theory behind digital technology and provided hands on design, as well as installation and commissioning information to guarantee reliable system performance. The DM Certification program ensures that AV professionals are fully educated and understand the implications of digital content in AV designs.

See photos following the text of this post.

The new Mukilteo Community Center can host a variety of functions, including community theater groups, dance groups, lectures and presentations, weddings, film presentations, community auctions, and dinners. The main space may be set up as either one large room with a seating capacity of up to 500 people in concert seating, or divided into two spaces by an operable partition that divides the space equally when deployed. In this mode, the front half of the space may be used with the stage. The sound systems accommodate this functionality in their operation and set-up, allowing simultaneous use of a sound system in each space.

The permanent video presentation systems will only be used when the room is operated as one large room or in the front half of the room when the partition is in place. An electrically-operated projection screen is located in the fly loft to allow projection of video signals from laptops or a DVD player.

Connections for a laptop and other portable video sources are provided in floor pockets on the stage and at the Stage Manager’s Panel backstage. A small portable rack with a DVD, video tape player, and an auxiliary input panel is provided next to the portable audio mixer for use during more complex shows. Video switching and signal processing are located in the backstage rack.

In addition to the extensive AV design work, BRC also provided design for architectural acoustics and mechanical noise control.

Entry

Fireplace Lounge

Stage

Mixing Board

Fitness Center

Reception Area